JP3000159B2 - Extubation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube for removing a tubular member such as a metal tube disposed inside a structure such as a heat exchanger or a condenser by a mechanical force such as hydraulic pressure. It concerns the device.

[0002]

2. Description of the Related Art A large number of pipes through which a fluid flows are installed in equipment such as a heat exchanger, a condenser or a boiler installed in a thermal or nuclear power plant or various chemical plants. These tubes are usually made of metal tubes, such as STB material, which can cause scale sticking, corrosion or breakage during prolonged use. Therefore, these devices require periodic inspection and replacement of the tubes, in which case it is necessary to withdraw many tubes in one operation. In general maintenance work, it is desirable that the work time be as short as possible in order to reduce the downtime of the entire equipment.However, in the maintenance work of equipment having a large number of pipes, the efficiency of pipe extraction work is a particular problem. Had become.

That is, in a device such as a heat exchanger, in order to pull out a large number of tubes firmly fixed to a structure such as a tube sheet, the tube sheet and the tube are connected with a hand tool such as a tube drill, a knockout tool or a collapsing tool. Attach the jig or wire to the end of the pipe after weakening the fixing force of the pipe, and pull out the pipes one by one using human power or the power of a winch or forklift. A metal core shaft (arrow) for drawing is screwed in, and the metal core shaft is clamped by a tube puller called a tube puller using a manual hydraulic pump and a hydraulic piston cylinder device, and a piston stroke of about 10 cm or more is performed. Only the hydraulic pressure is used to forcibly remove the tube, then the piston of the tube removal device is set free, and the cylinder is used instead of a hammer to withdraw the tube by hitting. , Then wrapped around the wire end of the tube projecting from once remove tubesheet extubation device, method overtake the tube to lead by the power of such manpower or forklifts and winches are known.

[0004]

A conventional pipe removal apparatus is a portable tool for forcibly removing a pipe firmly fixed to a pipe sheet by expanding a pipe end in an apparatus such as a heat exchanger with an oil pressure. However, in such a tube removing device, it is necessary to support the pull-out reaction force on the tube sheet and to remove the tube straight at a right angle from the tube sheet. Separate personnel are needed to hold the condition correctly. In addition, the stroke of movement of the piston performed by the operation of the handle of the manual pump in the conventional tube removing device is generally tens of centimeters, which is sufficient to forcibly release the firm fixation of the expanded portion. Since the length of the pipe is much shorter than the length of the pipe in this type of equipment, if the pull-out resistance of the pipe after detachment from the tube sheet is large, to remove the pipe with further hydraulic pressure, release the clamp of the pipe removal device. The piston must be returned to its original position, and the pipe removal device must be set again.Also, after removing the pipe to a certain length by hydraulic pressure, when removing the pipe with power such as human power or a winch, the removal of the pipe removal device must be performed. Removal work and mounting work of jigs and wires must be performed,
When extruding a large number of pipes, such operations must be performed for each pipe, which makes the extubation work complicated and takes a long time, and the efficiency of maintenance work for this type of equipment cannot be improved. There was a problem.

[0005] A main object of the present invention is to solve the above-mentioned problems and to provide a tube removing device capable of efficiently performing a drawing operation of a tube fixed to a structure or the like.

[0006] Another object of the present invention is to provide a tube removing device which can withdraw a tube over its entire length by a continuous repeated drawing operation while being set.

It is still another object of the present invention to provide a tube removing apparatus which can withdraw a tube at a relatively high speed by a continuous and repeated drawing operation.

It is still another object of the present invention to provide a tube removing apparatus which can withdraw a tube with a relatively strong force by a continuous repeated drawing operation.

Still another object of the present invention is to provide an extubation device capable of selectively switching between relatively powerful extubation and relatively high-speed extubation.

Still another object of the present invention is to provide a tube removing apparatus which can easily replace a tube clamp according to the diameter of a tube to be removed.

It is still another object of the present invention to provide a hydraulic tube removing apparatus which can perform the tube removing operation alone without using a winch or a forklift for tube removing.

[0012]

According to a first aspect of the present invention, there is provided a tube removing apparatus which moves a tube fixed to a structure in an axial direction so as to resist the drawing reaction force acting between the tube and the structure. A tube removing device for withdrawing from the structure, in order to achieve the above-mentioned object, a first and a second reciprocating device including a movable portion that is arranged in tandem in the axial direction and that repeatedly reciprocates in the axial direction. Moving device, and the movable portion of each of the first and second reciprocating devices and the tube are prevented from moving relative to each other in the axial direction only when the movable portion moves in the tube withdrawing direction. The one-way first and second force transmitting mechanisms for transmitting the pulling force to the pipe and the first and second reciprocating devices such that the movable portions of the first and second reciprocating devices reciprocate repeatedly in synchronization with each other. A driving device for driving the first and second reciprocating devices. That.

[0013] A tube removing device according to a second aspect of the present invention is the tube removing device according to the first aspect of the present invention, wherein the driving device is configured such that when one of the first and second reciprocating devices moves in the drawing direction, the other of the first and second reciprocating devices moves. And a control device for synchronously operating the first and second reciprocating devices at operation phases opposite to each other so that the movable portion returns to the opposite direction.

According to a third aspect of the present invention, there is provided the extubation device according to the first invention, wherein the driving device is configured so that the movable portions of the first and second reciprocating devices simultaneously move in the same direction. A control device for synchronously operating the two reciprocating devices at the same operation cycle as each other is provided.

According to a fourth aspect of the present invention, in the tube removing device according to the first aspect, the driving device is configured such that when one of the first and second reciprocating devices moves in the drawing direction, the other of the first and second reciprocating devices moves. A first control mode in which the first and second reciprocating devices are synchronously operated in operation phases opposite to each other so that the movable portions of the first and second reciprocating devices return in the opposite direction. A control device capable of selectively switching between a first control mode and a second control mode in which the first and second reciprocating devices are synchronously operated at the same operation cycle so that the units move in the same direction at the same time. Is what you do.

A tube removing device according to a fifth aspect of the present invention is the tube removing device according to the fourth aspect of the present invention, wherein the control device performs the second control mode in a state where the pipe is fixed to the structure. And a switching device for automatically switching the control mode so as to select the first control mode after the pipe is released from the fixation to the structure by pulling out the pipe.

According to a sixth aspect of the present invention, in the tube removing apparatus according to the first aspect, the first and second reciprocating devices each include a single-rod double-acting hydraulic piston-cylinder device, and the movable portion includes a hydraulic piston. These hydraulic piston cylinder devices are constituted by piston rods of the cylinder device, and these hydraulic piston cylinder devices are arranged in tandem in opposite directions with their ends on the piston head side facing each other, and the force transmission mechanism is attached to the piston rod of each of the hydraulic piston cylinder devices. It is characterized by being provided.

A tube removing device according to a seventh aspect of the present invention is the tube removing device according to the first aspect, wherein the first and second reciprocating devices each include a double-acting hydraulic piston-cylinder device, and the movable portion is a piston of each hydraulic piston-cylinder device. Each hydraulic piston cylinder device is constituted by a rod and contributes to the movement of the movable portion in the pull-out direction, so that the piston pressure receiving areas of the hydraulic piston cylinder devices are equal to each other.

In the tube removing apparatus according to the eighth invention, the tube fixed to the structure is moved in the axial direction, thereby pulling out the tube from the structure against the drawing reaction force acting between the tube and the structure. A tube removing device, comprising a hollow structure that is arranged in tandem in the axial direction, has a piston rod that reciprocates repeatedly with a predetermined stroke in the axial direction, and that allows passage of the tube in the axial direction. The first and second double-acting hydraulic piston-cylinder devices and the first and second hydraulic-piston-cylinder devices are integrally held, and can contact the structure to support the pull-out reaction force. A transport support structure and a piston rod provided in each of the first and second hydraulic piston cylinder devices, and the pipe or the pipe is only moved when the piston rod moves in the pipe withdrawing direction. The first and second hydraulic clamping devices that clamp the rod-shaped member connected to the hydraulic pressure and transmit the pulling force of the piston rod to the pipe, and the hydraulic oil supplied from the power-driven hydraulic pump. And a hydraulic drive control device for synchronously controlling the first and second hydraulic piston cylinder devices and the first and second hydraulic clamp devices based on a predetermined operation phase cycle based on the operation phase period.

A tubing device according to a ninth aspect of the present invention is the tube removing device according to the eighth aspect, wherein the hydraulic drive control device pulls out the piston rod to one or both of the first and second hydraulic piston cylinder devices. A means for applying vibration to the hydraulic pressure for moving the fluid in the direction.

[0021]

The invention according to the present invention is directed to a tube removing apparatus for removing a tube from a structure by moving a tube fixed to the structure in an axial direction against a drawing reaction force acting between the tube and the structure. , And are configured as described above, and thus have the following effects.

First, the tube removing device according to the present invention is a device for withdrawing a tube fixed to a structure, but the end of the tube to be removed does not sufficiently project from the structure, and the tube removing device is not used. If the tube cannot be clamped, a core shaft is connected to the end of the tube, and the tube removing device initially performs a tube removing operation via this core shaft. The core shaft referred to here is a generally rod-shaped member called a "mandrel" or "arrow", and has a connecting portion at its distal end which is engaged with a pipe to be extracted by engagement or the like. The configuration itself of the core shaft is not particularly limited as long as it can be coaxially connected to the pipe without much difference from that used in the conventional extubation device.

As the connecting portion provided at the end of the core shaft, the pipe to be extracted is often buried up to the pipe end in a structure such as a tube sheet, so that the core is connected from the outside to the opening at the pipe end. It is preferable that the shaft can be inserted and connected. For example, by simply screwing the tip end of the core shaft into the inner surface of the tube end, the outer periphery is cut into a groove having, for example, a circumferential inverted tooth that engages with the inner surface of the tube end so as to obtain a sufficient connection for pulling out. Surfaced connections are suitable for this purpose. Needless to say, such a connecting portion may be any as long as it can generate a sufficient coupling force to maintain the connection against the tensile stress acting when the tube firmly fixed to the structure is pulled out. In addition to the method, there are various forms depending on the object to be extruded, such as a pin connection or a bayonet connection between the core shaft and the tube, or a method in which a tab that is additionally welded to the tube for the extubation operation is fitted unevenly. The structure is not limited as long as it can be securely connected to the tube near the tip of the core shaft and can be removed from the tube after extubation.

Further, the connecting portion of the core shaft may include a rotary joint structure for absorbing a slight deviation of the coaxiality and angle between the tube and the core shaft. In addition to the strong connection, even if the drawing direction by the core shaft is slightly deviated from the axial direction of the pipe, there is no problem in the range where the tube is removed by the core shaft, and the removal operation proceeds and exceeds the length range of the core shaft. If the tube removing device clamps the tube, there is an advantage that the problem of runout can be solved.

The length of the core shaft does not have to be a so-called long object, and is at least as long as the core shaft reaches the initial clamping position of the tube removing device in a state of being connected to a pipe fixed to the structure. I just want it. Since the core axis is coaxially connected to the pipe so as to coincide with the axial direction (pull-out direction) of the pipe, the core axis connected to the pipe end protrudes from the structure in the extension direction of the pipe axis. The extruder according to the present invention is mounted on the protruding portion.

The outer shape of the core shaft is preferably a shape conforming to the outer shape of the tube, and is generally preferably a round bar having the same circular outer surface as the tube. This is because, as described later, the unidirectional first and second force transmitting mechanisms for transmitting the pulling force by each movable portion of the first and second reciprocating devices to the pipe first move the core shaft. This is because it is desirable for a smooth extubing operation to obtain a similar clamping state between the core shaft and the tube in order to clamp and clamp the tube after the extubating operation in the length range of the core shaft.

However, as long as the force transmission mechanism can generate a clamping force that is not so different from the shape other than the outer shape of the tube, the outer shape of the core shaft may be elliptical or polygonal. In order to transmit a sufficient pulling force required for initial extubation by the shaft, it is also possible to employ a core shaft having an outer shape most suitable for clamping by a force transmitting mechanism. The structure of the core shaft may be a solid structure or a hollow structure, and may be determined in consideration of a material, a cross-sectional dimension, and the like so as to sufficiently withstand a tensile load.

In the following description, as in many cases, the operation of the present invention will be described on the assumption that the above-described core shaft is connected to the end of the pipe to be extracted, and that the above-mentioned core shaft is connected. It should be noted that the tube removing device of the present invention does not necessarily require a core shaft.

Now, in the tube removing apparatus according to the first invention,
The first and second reciprocating devices are arranged in tandem substantially in the axial direction of the pipe to be extracted, and each has a movable portion that reciprocates repeatedly in the axial direction. The reciprocating range of each movable part of the first and second reciprocating devices is within the length range of the core shaft connected to the end of the tube in the initial set state, and this means that It means that the core shaft is selected and that the extubation device is arranged at such a position.

The first and second force transmitting mechanisms are unidirectional, and the first and second reciprocating devices move the respective movable parts of the first and second reciprocating devices and the pipe in the axial direction by the movable mechanism. Only when the part moves in the tube withdrawing direction, it blocks and transmits the pulling force by the movable part to the pipe, and the first and second reciprocating devices are such that each movable part of each other is synchronized with each other. It is driven by a driving device so as to reciprocate repeatedly.

That is, each movable portion of the first and second reciprocating devices is clamped by the first and second force transmitting mechanisms to the core shaft or the tube only when both move in the pulling-out direction. When it moves in the direction, it can be returned free from the core shaft or the tube. By the unidirectional clamping function of such a force transmitting mechanism, the force in the pulling direction by each movable portion is transmitted to the core shaft and the tube connected thereto, and the core shaft is first driven in the pulling direction, The tube connected to the mandrel is forcibly pulled out of the structure. Each of the movable parts of the first and second reciprocating devices is driven by the driving device so as to reciprocate repeatedly in synchronization with each other, and after the length of the core shaft has been withdrawn, the force transmitting means moves the tube. It is directly clamped, so that the entire length of the tube is removed from the structure by the power of the first and second reciprocating devices. In this case, there is no need to reset the device or replace it with another power extraction device or the like in the middle of the tube removal as in the related art.

In the first invention, the reciprocating motion of the movable portions of the first and second reciprocating devices is determined by a predetermined moving stroke, that is, the force applied to each movable portion determined for each reciprocating device. This is performed for a stroke section between the clamp position of the core shaft or the tube and the clamp release position by the transmission mechanism. In this case, the moving strokes of the movable portions in the respective reciprocating devices may be equal or different from each other, and may be determined in consideration of the output torque, speed, and the like of each reciprocating device. The magnitude of the force to be generated by each reciprocating device is large enough to pull out the core shaft clamped by the force transmission mechanism or the tube connected thereto from the structure, for example, a tube having an outer diameter of about 15 mm. About 70 × 10 ³ N or more, and about 240 × 10 ³ N or more for the removal of a pipe having an outer diameter of about 50 mm.
Further, if the first and second reciprocating devices are simultaneously pulled out, it is possible to generate up to double the respective forces.

These reciprocating devices need only be capable of providing a predetermined mechanical output and reciprocating so as to pull out a tube or a core shaft connected thereto through a force transmission mechanism at a predetermined stroke. Specifically, a double-acting hydraulic piston cylinder device is preferable, but a mechanical output by a power device such as an electric motor or another fluid motor may be used depending on the application.

The first and second reciprocating devices are arranged in tandem, in other words, substantially in series in the axial direction.
In this case, it is only necessary to select an arrangement such that at least the movable part and the force transmitting mechanism do not mechanically interfere with each other during operation, which is the joint operation of the first and second reciprocating devices. This is to cause high-speed or strong extubation.

The first force transmitting mechanism is provided on the movable portion of the first reciprocating device, and the second force transmitting mechanism is provided on the movable portion of the second reciprocating device. These force transmission mechanisms prevent the relative movement between the movable part and the pipe by clamping the pipe or the core shaft connected thereto only when each movable part moves in the pulling-out direction. It is sufficient if the movable part moves in the direction opposite to the drawing direction when the movable part moves in the direction opposite to the drawing direction, and the movable part moves with respect to the pipe or the core shaft connected thereto. The clamp by the force transmission mechanism is released so that it can move freely.

As such a one-way force transmission mechanism, various chuck devices for gripping the shaft, for example, an externally operated chuck device which is opened and closed by a fluid-operated clamp piston, or biased by a spring force. Although a self-acting chuck device using a one-way ratchet mechanism or the like can be used, in the present invention, even when the outer diameters of the core shaft and the tube are different or different from each other, a strong clamp is similarly used. It is preferable to use one that can achieve the following. For this purpose, for example, a collet chuck type hydraulic clamping device can provide a strong clamping force corresponding to the pull-out reaction force of a pipe over a certain diameter range, and can synchronize the first and second reciprocating devices. It is particularly suitable for the force transmission mechanism of the tube removing device according to the present invention because, for example, a relatively simple hydraulic control system can open and close with high response without a timing delay with respect to repeated reciprocating motions caused by operation. .

In any case, it is desirable that these force transmission mechanisms can be compactly incorporated into the movable part, and the function is to clamp the pipe or the core shaft connected thereto only when the movable part moves in the pulling-out direction. The clamp may be released when the movable part moves in the opposite direction, and the clamp may be opened or closed by a self-acting method using a spring force or an external operating method using a hydraulic or electromagnetic force.

The shape of the clamp engagement surface of the force transmission mechanism is generally such that the outer surfaces of the core shaft to be clamped and the tube to be removed are often smooth surfaces. It is preferable to have a claw-like rack tooth shape that produces strong engagement in the pulling direction with respect to the rack.

The first and second reciprocating devices are driven by a driving device, and the driving devices respectively move the movable portions of the first and second reciprocating devices so as to repeatedly reciprocate in synchronization with each other. Control the operation of. By such a synchronous and repetitive drive, the tube removing device according to the present invention can withdraw the tube from the beginning to the end over the entire length thereof while being set in the tube to be removed, so that one tube is removed. There is no need to perform extra work such as replacement during the extubation work.

The movement strokes of the first and second reciprocating devices are determined by, for example, using a limit switch,
It can be set by various control methods such as detecting with a position detector such as a differential transformer, proximity switch, or photo sensor and using it for reversing the reciprocating motion by the drive device. You can also adjust the stroke.

Further, when the tube is completely pulled out of the structure, it is necessary to stop the operation of the reciprocating device.
Whether the pipe has been pulled out is determined by an electric manual method by operating a stop switch based on visual confirmation by the operator,
Alternatively, it is possible to use any of the automatic methods for automatically detecting the withdrawn state of the pipe. The detection means in the case of the automatic method is not particularly limited as long as it can detect that the pipe has been almost completely pulled out of the structure. A sensor that detects by contact, a sensor that detects that the force transmission mechanism located closest to the structure side can no longer be clamped due to the absence of a pipe, or a load torque when the movable part moves in the withdrawal direction For example, a sensor that detects a sudden decrease in the speed or a sudden increase in the moving speed can be applied, and a method of stopping the operation of the driving device based on a signal from these sensors can be considered. As a result, it is possible to automatically control the prevention of an accident due to the so-called idle feeding operation after the complete withdrawal, and to suppress unnecessary energy consumption and the like.

At the time of extubation, a pull-out reaction force acts on the apparatus. This can be achieved, for example, by providing a support structure for supporting the extubation apparatus in contact with a structure to which the pipe is fixed. However, the configuration of such a support structure itself is not much different from the case of the conventional extubation device.

In the second invention, the driving device in the tube removing device according to the first invention is arranged such that, when one of the first and second reciprocating devices moves in the drawing direction, the other of the moving members reverses. A control device is provided for synchronizing the first and second reciprocating devices with operation phases opposite to each other so as to perform a return operation in the direction, thereby enabling high-speed extubation.

That is, while the first reciprocating device is performing the withdrawing operation of the tube, the second reciprocating device performs the returning operation in the reverse direction, and conversely, the second reciprocating device performs the withdrawing operation of the tube. During the operation, the first reciprocating device performs a return operation in the reverse direction, and by repeating such an alternating operation with the operation cycle of the opposite phase synchronously, the pipe is almost continuously moved in the drawing direction. Until it is moved and its entire length is completely withdrawn from the structure, the two reciprocating devices interpolate the return time of each other and perform a continuous, high-speed extubation operation without waste. In this case, when the movable part of each reciprocating device moves in the direction opposite to the pull-out direction, the movable part freely returns and moves because the clamp on the pipe by the one-way force transmission mechanism does not work,
Therefore, the individual load torque at the time of the return operation of each reciprocating device is extremely lower than at the time of pull-out.

When the first and second force transmitting mechanisms are of an external operation type, the timing of starting and releasing the clamp is adjusted in accordance with the timing of the pull-out operation and the return operation of the first and second reciprocating devices. The control may be performed alternately.

According to a third aspect of the present invention, the driving device in the tube removing apparatus according to the first aspect of the present invention is configured such that the first and second reciprocating devices move so that the movable portions of the first and second reciprocating devices simultaneously move in the same direction. A control device for synchronizing the moving devices with the same operation cycle is provided, so that the pulling forces of the first and second reciprocating devices simultaneously act on the pipes, so that strong pulling can be performed.

That is, when the first reciprocating device performs the pulling operation of the pipe, the second reciprocating device also performs the pulling operation in synchronization, and when the first reciprocating device performs the returning operation in the reverse direction, the second reciprocating device performs the returning operation. The two reciprocating devices also perform a return operation, and by repeating such an alternating operation with the same phase operation cycle in synchronization, the pipe is intermittently moved in the withdrawing direction by the total pulling force of both reciprocating devices. You.

Also in this case, if the first and second force transmitting mechanisms are externally operated, the timing of starting and releasing the clamp is determined by the pull-out operation and the return of the first and second reciprocating devices. What is necessary is just to perform simultaneous control according to the operation timing.

According to a fourth aspect of the present invention, the driving device in the tube removing apparatus according to the first aspect of the present invention is configured such that when one of the first and second reciprocating devices moves in the drawing direction, the other movable portion moves. A first control mode in which the first and second reciprocating devices are synchronously operated at opposite phase operation cycles so as to perform a returning operation in the opposite direction, and each movable portion of the first and second reciprocating devices is A control device capable of selectively switching between a first control mode and a second control mode in which the first and second reciprocating devices are synchronously operated at the same operation cycle so as to move in the same direction at the same time. By selectively switching between the first control mode and the second control mode, high-speed extubation and high-strength extubation can be switched.

For example, when the structure to be extubated is a device such as a heat exchanger, the tube is firmly fixed to the tube sheet by expanding the end of the tube. A strong pulling force is required at the initial stroke stage of the tube removing operation in order to forcibly release such a sticking. For such a strong withdrawal in the initial stage of the extubation, the second control mode is selected by the control device, and the first and second reciprocating devices are simultaneously withdrawn so that a strong pulling force is obtained by the total pulling force of the two. Extubation can be performed.

Further, the pull-out resistance after the pipe is separated from the tube sheet is almost entirely due to the frictional force associated with the pull-out from the tube sheet, and the pipe can be pulled out with a lower pulling force than when the fixing is released. After the initial stage, the first control mode is selected by the control device, and the first and second reciprocating devices can be operated synchronously with the operation cycles of opposite phases to perform high-speed extubation.

The selection of the control mode may be performed by setting the phase of the synchronous operation of the first and second reciprocating devices by the driving device to the opposite phase (first control mode) by the control device.
Alternatively, it can be realized by switching between in-phase (second control mode). The switching of the control mode can be performed manually, but according to the fifth invention, the control device includes an automatic switching device for these control modes. This automatic switching device selects the second control mode when the pipe is firmly fixed to the structure, and the first control mode after the pipe is removed from the structure by the withdrawal in the second control mode. The control mode is automatically switched so as to select the control mode. As a switching control method of the automatic control device, for example, each reciprocating device operates in the second control mode for the initial few strokes, and then operates in the first control mode by sequence control based on the counting result by the counter of the number of strokes. A method of automatically switching modes can be adopted, or
For example, the mode is automatically changed from the second control mode to the first control mode by comparison with a reference value preset and adjusted based on a signal from a sensor for measuring the above-described load torque, drawing speed, or pipe drawing amount, and the like. A switching method can also be adopted.

According to a sixth aspect of the present invention, in the extubation device according to the first aspect, the first and second reciprocating devices each include a single-rod double-acting hydraulic piston-cylinder device, and the movable portion includes a hydraulic piston-cylinder device. These hydraulic piston cylinder devices are arranged in tandem with the piston head side ends facing each other in opposite directions, and the force transmission mechanism is attached to the piston rod of each of the hydraulic piston cylinder devices. Is provided.

This is because the first and second hydraulic piston cylinder devices are of a single rod type, and the piston head side ends thereof are arranged so as to face each other. Each part faces outward,
The incorporation of the force transmission mechanism into each of the outwardly facing piston rods eliminates the need to disassemble the device when, for example, replacing the clamp portion of the force transmission mechanism for maintenance or to deal with an irregular pipe. It has the advantage that.

According to a seventh aspect of the present invention, in the tube removing apparatus according to the first aspect, the first and second reciprocating devices each include a double-acting hydraulic piston-cylinder device, and the movable portion is formed by a piston rod of each hydraulic piston-cylinder device. Composed,
Each hydraulic piston cylinder device that contributes to the movement of the movable portion in the pull-out direction is configured to have equal piston pressure receiving areas.

For example, when the first and second reciprocating devices each include a single-rod type double-acting hydraulic piston-cylinder device, as is well known, in a single-rod-type cylinder device, the pressure receiving area of the piston is on the head side and on the rod side. And are different. If these hydraulic piston cylinder devices are arranged in tandem with the ends on the piston head side facing each other, the piston pressure receiving area contributing to the pulling force in one cylinder device is on the head side, and the other is on the other side. In the cylinder device, this is the rod side, and if the supply hydraulic pressure for the synchronous operation is the same, the pulling forces by the cylinder devices will be different from each other.

Therefore, in the seventh aspect, even in such a case, the piston pressure receiving areas which contribute to the pulling force of each cylinder device are made equal, and the pulling forces by the cylinder devices are made equal to each other. For example, the bore diameter of one single-rod type hydraulic piston cylinder device in which the piston pressure receiving area on the head side contributes to the pulling force is the same as that of the other single rod type hydraulic piston cylinder device in which the piston pressure receiving area on the rod side contributes to the pulling force. The diameter is smaller than the diameter.

An eighth aspect of the present invention is to provide a hydraulic tube removing apparatus which can perform the tube removing operation alone without using a winch or a forklift for the tube removing.
In this hydraulic pipe removal device, first and second double-acting hydraulic piston cylinder devices are arranged in tandem in the axial direction of a pipe fixed to a structure, and these hydraulic piston cylinder devices are respectively predetermined in the axial direction. It has a piston rod that reciprocates repeatedly with a given stroke, and has a hollow structure that allows the passage of the pipe in the axial direction. The portable unit is integrally supported by a portable support structure capable of contacting the structure.

A first hydraulic clamping device is provided on the piston rod of the first hydraulic piston cylinder device,
A second hydraulic clamping device is provided on the piston rod of the second hydraulic piston-cylinder device, and these hydraulic clamping devices are provided only when each piston rod moves in the withdrawal direction. A rod-like member such as a shaft is clamped by a hydraulic operating force to transmit a pulling force by a piston rod to the pipe.

The first and second double-acting hydraulic piston cylinder devices and the first and second hydraulic clamping devices are controlled in advance by a hydraulic drive control device based on pressure oil supplied from a power driven hydraulic pump. Synchronous control is performed at a predetermined operation phase cycle.

The first and second hydraulic piston cylinder devices in this case can also be of the single-rod type, and preferably the single-rod first and second hydraulic piston-cylinder devices have their piston heads. Side ends are arranged facing each other. Thereby, the ends on the piston rod side of the two cylinder devices face outward, respectively.By incorporating the force transmitting mechanism into each piston rod facing outward, for example, the force transmitting mechanism can be used to cope with maintenance or irregular pipes. When the clamp part is replaced, it is not necessary to disassemble the apparatus.

The first and second hydraulic piston-cylinder arrangements have a hollow structure for passing the pipe in the axial direction, so that their piston rods have an axial through bore. The first and second hydraulic clamp devices are preferably a clamp piston constituting a single-acting piston-cylinder device that is moved and operated by hydraulic pressure from a hydraulic drive control device, and a collet chuck that is opened and closed by movement of the clamp piston. Which are integrated into a hollow piston rod having an axial through bore.

The collet chuck is a hollow cylindrical chuck assembled into a frusto-conical outer shape by a plurality of divided bodies by slitting, and is inserted into a hole on the inner surface of the cone that matches the conical surface on the outer surface. Then, the object (core shaft or pipe) is clamped on the chuck surface on the inner surface of the hole by reducing or expanding the diameter of the hollow hole by the relative movement in the axial direction, or the clamp is released.

For example, by applying a hydraulic operating force to the clamp piston, the collet chuck closes so as to reduce the diameter, whereby the core shaft in the through bore or the tube connected thereto is gripped with a strong clamping force. Although it depends on the outer diameter of the tube to be extruded, for example, when a tube having an outer diameter within a range of about 10 to 80 mm is to be extruded, an effective chuck of a collet chuck opened and closed by a clamp piston incorporated in a piston rod. The diameter can be designed, for example, to have a width of about −6 mm to +30 mm of the nominal chuck diameter.

As described above, when the hydraulic clamping device is in the clamped state, the hydraulic piston cylinder device is driven by the hydraulic pressure, and the pipe is pulled out by the movement of the piston rod. When the piston rod returns in the reverse direction, in the hydraulic clamping device for the piston rod, the clamp piston retreats to open the collet chuck and release the clamp of the core shaft or the tube connected thereto. The opening and closing operation of the first and second hydraulic clamp devices is performed by the hydraulic drive control device in response to the repetitive reciprocating motion caused by the synchronous operation of the first and second reciprocating devices at a high timing. Controlled by sex.

The hydraulic drive control device generally includes a hydraulic pump device that is driven by a rotary power source such as an electric motor, and in some cases, an air motor or an internal combustion engine. And preferably includes a plurality of electromagnetic switching valves and an excitation control circuit thereof for controlling the synchronous operation of the reciprocating reciprocating motion of the first and second hydraulic piston cylinder devices and the opening and closing operations of the first and second hydraulic clamping devices. It can be constituted by a hydraulic system provided with a control device.

In this hydraulic system, since the pressure flow characteristic of the load pulsates due to the reciprocating operation described above, preferably, the hydraulic pump device includes a high-pressure small-capacity pump and a low-pressure large-capacity pump connected via a check valve. An energy-saving pump circuit combining a high pressure setting relief valve and a low pressure setting unloading valve. In such a pump circuit, when the hydraulic piston cylinder device performs a return operation, the circuit has a low load, so that the discharge flow rate from the high-pressure pump and the discharge flow rate from the low-pressure pump that merges via the check valve are unloaded from the relief valve The sum is kept at a pressure lower than the set pressure of the valve and sent to the hydraulic piston cylinder device, whereby the piston rod returns at a relatively high speed with a low torque.

On the other hand, since the circuit has a high load during the drawing operation, the discharge flow rate from the high-pressure pump is sent to the hydraulic piston cylinder device at a high pressure set by the relief valve. Becomes higher than the set pressure of the unload valve, so the unload valve opens the oil passage and connects the discharge oil passage of the low pressure pump to the tank line, and the discharge flow rate from the low pressure pump to the tank at low pressure close to no load It is refluxed. At this time, a high pressure is applied to the check valve from the high pressure pump side, so that the discharge oil passage of the low pressure pump is blocked from the oil passage leading to the load from the high pressure pump. In this state, power is mainly consumed only by the high-pressure pump, thus saving energy.
It is needless to say that such an energy-saving pump circuit can be constituted by one two-pressure / two-capacity control type variable displacement pump.

In the hydraulic drive control device, the pump circuit controls the switching of the moving direction of the piston rod of each hydraulic piston cylinder device and the opening and closing of each hydraulic clamp device synchronously by excitation control by the control circuit. Synchronous control of the repetitive switching operation of the electromagnetic switching valves provided in the respective hydraulic oil supply oil passages to the hydraulic piston cylinder device and the hydraulic clamp device is performed.

In this case, preferably, in order to adjust the piston moving speed in one or both of the reciprocating strokes of each hydraulic piston cylinder device and each hydraulic clamp device,
A flow control valve or a flow control valve is provided in the oil passage leading to these cylinders, and individual piston movement speeds can be obtained by meter-in or meter-out control. To be adjusted.

The control device mainly comprises an excitation control circuit for controlling each of the electromagnetic switching valves. The periodic synchronous switching of each of the electromagnetic switching valves is performed when the piston rod of each hydraulic piston cylinder device reaches the stroke end. Is detected by, for example, a pair of limit switches arranged at predetermined intervals, and the excitation of each electromagnetic switching valve is switched so that reciprocation is reversed by this detection signal. For example, when the limit switch at one stroke end generates a signal at the end of the withdrawal operation, the excitation of the electromagnetic switching valve is switched so as to reverse the hydraulic piston cylinder device to the return operation, and at the end of the return operation, the other limit switch Generates a signal, the excitation of the electromagnetic switching valve is switched so that the hydraulic piston cylinder device is reversed to the withdrawing operation after a predetermined delay time provided as necessary.

The electromagnetic switching valve for switching between the supply of pressure oil to each hydraulic clamping device and the return to the tank is also described.
Similarly, synchronous control can be performed with a detection signal from a limit switch that detects the stroke end. According to the above example, for example, at the end of the withdrawal operation of the first hydraulic piston cylinder device, the limit switch at one stroke end Generates a signal, the excitation of the electromagnetic switching valve is switched so that the first hydraulic clamping device releases the clamp before the return reversal operation after the piston rod stops, and the other end is returned to the end of the return operation. When the limit switch generates a signal, the excitation of the electromagnetic switching valve is switched so as to perform a clamping operation immediately before the first hydraulic piston cylinder device starts operating in the withdrawal direction in synchronization with the signal.

Similarly, in the second hydraulic clamping device, the respective solenoid-operated directional control valves are synchronously controlled in relation to the operation of the second hydraulic piston-cylinder device. Repeat operation, during which each hydraulic piston cylinder device performs synchronous control such that the other hydraulic piston cylinder device performs the pulling operation only while the hydraulic clamping device of one hydraulic piston cylinder device releases the clamp Is done.

Regarding the start and stop of the overall operation by the hydraulic drive control device, for example, one electromagnetic valve is interposed as a main valve in the discharge oil passage of the pump circuit leading to each electromagnetic switching valve, and the excitation of this is performed. It is possible to perform on / off switching by a manual operation switch of a worker. In this case, the electric motor for driving the pump of the hydraulic control device may be kept operating by turning on the main power supply, and the main valve is opened by the manual operation switch and each electromagnetic switching valve is started to operate from a predetermined initial switching function. If this is done, the operator can set the core shaft and the portable unit of the extubation device to the target pipe, and immediately operate the local operation switch to perform the extubation work. Thus, a large number of pipes can be successively hydraulically extruded over the entire length.

The above is the control mode of the high-speed extubation by the opposite-phase cyclic operation of both the hydraulic piston-cylinder devices. Can be performed. In this case, the electromagnetic switching valves for switching the operating directions of both the hydraulic piston cylinder device and the hydraulic clamping device may be periodically operated in the in-phase switching mode, and the polarity of the exciting current of each electromagnetic switching valve is controlled in the control device. It is easily possible by appropriate selection, and if such polarity selection can also be performed by the above-mentioned hand operation switch, the operator can switch between high-speed extubation and strong extubation at any time during extubation work. it can.

In the ninth invention, the hydraulic pressure is additionally applied to the supply pressure oil for the above-described operation of extracting the hydraulic piston cylinder device, thereby causing the extraction force to vibrate. In this case, for example, for a supply pressure oil whose flow direction is selected by an electromagnetic switching valve, for example, an electromagnetic flow control valve is used as a flow control valve for adjusting the flow rate, and dither is added to an exciting current of the electromagnetic flow control valve. Hydraulic vibration can be given. When a pulling force including such vibration is applied to the pipe, friction between the pipe and the structure is reduced, and pulling is facilitated.

To clarify the above and other features and advantages of the present invention, preferred embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. It goes without saying that various modifications within the technical scope of the present invention are possible with the knowledge of those skilled in the art.

[0078]

FIG. 1 is a vertical sectional view showing a schematic configuration of a portable cylinder unit which is a main part of a tube removing apparatus according to an embodiment of the present invention, and FIG. 2 is an overall configuration of the tube removing apparatus of this embodiment. Is shown. As shown in the figure, the tube removing apparatus of the present embodiment axially removes a tube 92 which is firmly fixed to a tube sheet 91 of a heat exchanger shown as an example of a structure to be removed by expanding a tube end. And the portable cylinder unit 1
00 and a control unit 2 as its driving device
00.

In FIG. 1, a core shaft (arrow) 95 is inserted into a tube end opening of a tube 92 to be extracted, which is viewed from the outer surface of a tube sheet 91, and the taper of the core shaft 95 is tapered in the manner of a manual tap. A serrated engagement screw groove 96 formed on the outer peripheral surface of the distal end portion is screwed into the inner surface of the tube 92 by screwing, whereby the tube 92 and the core shaft 95 are coaxially connected. Details of the core shaft 95 used in this embodiment are shown in FIG. That is, the core shaft 95 in this case is the tube 9 to be extubated.
2 is formed of a metal round bar of, for example, carburized steel having substantially the same outer diameter as that of FIG. Is provided with a square portion 97 for applying a hand tool (for example, a spanner) for screwing engagement with the tube 92.

The engaging screw groove 96 may be a tooth having a shape that bites into the inner surface of the pipe in the pulling direction. In the illustrated example, it is used for forming a cutting edge and a tip pocket like a screw portion of a hand-operated tap. It is formed as a spiral serrated screw groove interrupted by a notch 98 at a part in the circumferential direction. The square portion 97 does not need to protrude from the tail end of the core shaft, and may be, for example, a two-way portion formed on the peripheral surface of the tail portion of the core shaft.

As described above, when the tapered tip of the core shaft 95 is inserted into the pipe end of the pipe 92, and the square section 97 at the tail end is turned with a tool to screw the screw groove 96 into the inner surface of the pipe 92, The screw groove 96 bites into the inner surface of the tube 92 while shaving and engaging with it, so that the core shaft 95 is securely connected to the tube 92.

In FIG. 1, the portable cylinder unit 10
Reference numeral 0 denotes a set state in which the portable cylinder unit is in contact with the tube plate 91 so as to surround the core shaft 95 connected to the pipe 92. In practice, the portable cylinder unit is held in such a set state by an operator's hand. An extubation operation is performed. In this case, the weight of the portable cylinder unit 100 is supported by hanging the unit 100 with a spring balancer (not shown) by attaching a wire 109a to a hanging fitting 109 provided on the unit 100, and an operator is fixed to the unit 100. It is preferable to hold the set handle 108 and hold it in the set state. The balancer can move the portable cylinder unit 100 freely up, down, left, and right, so that the burden on the operator can be reduced when performing many pipe removal operations one after another.

As shown in FIG. 1, the cylinder unit 10
Numeral 0 has a hollow structure having a through bore 102 along the central axis, and the core shaft 95 and the pipe 92 connected thereto are withdrawn through the through bore 102. The cylinder unit 100 is provided with a collar 1 which is in contact with the tube sheet 91 at the end.
03 is configured as a portable unit in which a pair of hydraulic piston cylinder devices 110 and 120 are integrally incorporated in a tandem arrangement into a support structure 101 having a detachable support rod 03.
1 and 121 include hydraulic clamping devices 130 and 14 having a chuck diameter range suitable for the outer shape of the core shaft 95 and the pipe 92.
0 is incorporated.

The hydraulic piston cylinder device 110 constitutes a first reciprocating device, and the hydraulic clamp device 130 incorporated in the piston rod 111 constitutes a first force transmitting mechanism. Similarly, the hydraulic piston cylinder device 120 constitutes a second reciprocating device, and its piston rod 121
The hydraulic clamping device 140 incorporated in the device constitutes a second force transmission mechanism.

The two hydraulic piston cylinder devices 110 and 120 are configured as independent single-rod double-acting piston cylinder devices coaxially tandemly arranged in a common cylinder body 104 fixed to the support structure 101. And the respective head side cylinder chambers 112 and 1
22 face each other with a partition 105 therebetween. That is, the piston rod 111 extends forward from the piston 113 of one hydraulic piston cylinder device 110 toward the collar 103, and the piston rod 121 extends backward from the piston 123 of the other hydraulic piston cylinder device 120. Are there.

In this case, in one hydraulic piston cylinder device 110, the piston rod 111 moves in the pulling-out direction when the pressure oil is supplied to the rod-side cylinder chamber 114, and the pressure oil is supplied to the head-side cylinder chamber 112. When the pressure oil is supplied to the head side cylinder chamber 122 of the other hydraulic piston cylinder device 120, the piston rod 121 moves in the withdrawal direction. When the pressure oil is supplied to the rod-side cylinder chamber 124, it moves in the return direction.

In order to supply and discharge the pressure oil as described above, the cylinder body 104 is provided with ports 106 _AH , 106 _AR , 106 _BH , and 106 _BR which individually communicate with the respective cylinder chambers. It is connected to the control unit 200 by a hydraulic hose.

In this embodiment, the pressure receiving area of the piston 113 in the rod side cylinder chamber 114 of the hydraulic piston cylinder device 110 and the hydraulic piston cylinder device 1
The piston 12 in the head side cylinder chamber 122 of FIG.
3 are equal to each other so that the pistons 113 and 123 of both cylinder devices have different outer diameters, so that when driven at the same supply pressure,
The mechanical outputs of the two hydraulic piston cylinder devices 110 and 120 arranged in tandem in opposite directions during the pulling operation are made equal.

In order to detect the stroke end of the reciprocating motion of each of the piston rods 111 and 121 of each of the cylinder devices 110 and 120, a pair of magnet-type proximity members spaced at predetermined intervals are provided on the support structure 101. Switches S _A1 and S _A2 and S _B1 and S _B2 are mounted, and each piston rod 11 is used as a detecting member for these proximity switches.
Magnets M _A and M _B are individually attached to the outer surfaces of the reference numerals 1 and 121. Detection signals of the proximity switch is directed to the control unit 200 by a cable code C _C. It goes without saying that a contact detecting means such as another non-contact detecting sensor or a limit switch may be used instead of the proximity switch.

FIG. 1 shows a state in which the piston rods 111 and 121 of each hydraulic piston cylinder device are both at the pull-out standby position, that is, the position where the movement in the pull-out direction is started. The respective piston rods move from the standby position to the right in FIG. 1 to perform the withdrawing operation, and then reverse and perform the returning operation. The stroke range of the reciprocating movement is determined by the proximity switches S _A1 and S _{A2, respectively.}
And the interval between S _B1 and S _B2 can be adjusted in advance. In this embodiment, the stroke amounts of the hydraulic piston cylinder devices are made equal to each other.

The hydraulic clamping devices 130 and 140 incorporated in the piston rods 111 and 121 of each hydraulic piston cylinder device are pivoted on the piston rods so as to form clamp cylinder chambers 131 and 141 between the respective piston rods. Pistons 132, 142 having the same pressure-receiving area incorporated so as to be slidable relative to each other.
And three-part type collet chucks, each of which is guided by conical tapered inner surfaces 138 and 148 formed on the inner peripheral surface of the distal end of each piston rod and axially moved by the clamp piston to change the inner peripheral chuck diameter. 1
33, 143.

The clamp cylinder chamber and the clamp piston of each of the hydraulic clamp devices 130 and 140 constitute a single-acting hydraulic piston cylinder device in principle, and both of them introduce predetermined high-pressure oil into the clamp cylinder chamber. To close the collet chuck and perform the clamp,
By reducing the pressure in the cylinder chamber to the tank line, the clamp by the collet chuck is released. In order to supply and discharge the pressurized oil, the piston rods 111 and 121 of each hydraulic piston cylinder device have ports 107 communicating with the clamp cylinder chambers 131 and 141, respectively.
a, 107b, and these ports are also connected to the control unit 200 by separate hydraulic hoses.

Since the hydraulic clamping devices 130 and 140 have the same configuration, FIG. 4 shows the configuration of one hydraulic clamping device 130 as an example. 4A is a rear view of the collet chuck 133 viewed from the clamp piston side in the axial direction, FIG. 4B is a cross-sectional view taken along the line bb of FIG. It is an expanded sectional view shown in the section along the axial direction.

The collet chuck 133 of this embodiment is a cylindrical collet chuck having a three-part conical tapered outer surface made up of three collet pieces 133a, 133b, and 133c. An axial through hole 135 for passing the pipe 92 is formed. The inner surface of the through-hole 135 is a reverse tooth-shaped clamping surface that is strongly engaged with the outer surface of the core shaft or the pipe in the drawing direction by the serrated thread grooves 134 formed in each collet piece.

The three-part collet chuck 133 is designed to have a smaller diameter than the inner diameter of the through bore 102 so that the collet chuck 133 can be replaced from the tip of the piston rod 11 in the most reduced state. In the assembled state, an elastic retaining ring 137 such as a rubber ring or an O-ring is fitted in a peripheral groove 136 provided on the outer surface of the collet so that they do not separate from each other. In some cases, a spring may be interposed between the collet pieces so that the collet chuck 133 is always provided with an urging force in the clamp releasing direction.

The outer peripheral surface of the collet chuck 133 is a conical tapered surface tapering toward the collar 103 (FIG. 1), and the inner surface of the piston rod 111 has a tapered surface corresponding to this tapered surface. A face 138 is formed,
The force of the clamp piston acting axially forward (in the direction toward the collar 103) on the collet chuck 133 is converted into a radial clamping force by the cam operation by the sliding contact guide between the tapered surfaces.

In FIG. 4C, when a predetermined high-pressure oil is introduced into the clamp cylinder chamber 131 from the control unit 200 via the port 107a, the clamp piston 132 moves forward as indicated by an arrow f and the collet piece 13
3a to 133c are pressed, whereby the collet chuck 133 is reduced in diameter and clamped, so that the piston rod 111 and the core shaft or the pipe 92 cannot be relatively moved. Conversely, when the hydraulic pressure in the clamp cylinder chamber 131 is reduced to the tank line, the clamp of the collet chuck 133 is released, and the piston rod 111 and the core shaft or the pipe 92 can relatively move.

[0098] Now, the configuration described above of the portable cylinder unit 100 is connected to the control unit 200 by all hydraulic hoses and cables code C _C described above, as shown in FIG. 2, the control unit 2
00 is supplied with power from a commercial power supply by a power cord 202, and a remote switch box 201 is connected to the control unit 200 in order to operate the tube removing device at hand by an operator.
Is used, for example, on the waist of a worker.

Control unit 2 in this embodiment
00 has a system configuration as shown in FIG. 5 as a hydraulic circuit diagram. 5, parts corresponding to those in FIGS. 1 and 2 are denoted by the same reference numerals, and each of the hydraulic cylinder units 110 and 120 and each of the hydraulic clamp units 130 and 140 of the portable cylinder unit 100 described above.
Are also indicated by hydraulic circuit symbols.

The control unit 200 controls the hydraulic ports 106 _AH , 10 of the portable cylinder unit 100.
6 _AR , 106 _BH , 106 _BR , 107a and 107b and hydraulic ports 206 _AH ,
206 _AR , 206 _BH , 206 _BR , 207a and 207
b, the aforementioned cable cord C _C and the switch box 20
1 are provided at the lower part of the front surface of the housing.

In FIG. 5, the control unit 20
0 is provided in the hydraulic power unit 21.
0, a plurality of 4-port two-position solenoid-operated directional control valves VA, VB,
Va, Vb, VM, a plurality of checked flow control valves VF _AH , VF _AR , VF _BH , VF _BR , throttle check valves VTa, VTb, pressure reducing valve VR, pulling force display pressure measuring device P1, clamping force display pressure Measuring instrument P
2, and an electric control circuit 220 for controlling the excitation switching of each electromagnetic directional control valve.

The hydraulic power unit 210 is
1, a high-pressure small-capacity pump 212 and a low-pressure large-capacity pump 213 which are commonly driven by
12 is connected to a relief valve 215 of a high pressure setting, and a discharge oil path of a low pressure pump 213 connected to a discharge oil path of a high pressure pump 212 via a check valve 214 is an unload valve 216 of a low pressure setting. A load pressure is guided to the unload valve from a discharge oil passage of the high-pressure pump 212 as pilot pressure, and outlet ports of the relief valve 215 and the unload valve 216 are connected to a reservoir 217, respectively. Reference numeral 218 denotes a level gauge that indicates the oil level in the reservoir 217.

This hydraulic power unit constitutes the above-described energy-saving pump circuit. When the circuit has a low load, the discharge flow rate from the high-pressure pump 212 and the check valve 2
And the discharge flow rate from the low-pressure pump 213 joining through the pressure control valve 14 is lower than the set pressure of the relief valve 215 and the unload valve 216, and the hydraulic piston cylinder device 1
10 or 120, which causes the piston rod to move relatively quickly with low torque. On the other hand, when the circuit has a high load, the discharge flow rate from the high pressure pump 212 is sent to the hydraulic piston cylinder device 110 or 120 at a high pressure set by the relief valve 215.
The pilot pressure by the discharge pressure of No. 12 is the unload valve 216
, The unload valve 216 drops the discharge oil passage of the low-pressure pump 213 to the tank line, and the discharge flow rate from the low-pressure pump 213 is returned to the reservoir 217 in a low-pressure state near no load. At this time, a high pressure is applied to the check valve 214 from the high-pressure pump 212 side.
Is blocked from the oil passage leading to the load. In this state, the power from the electric motor 211 is mainly
And thus power consumption can be saved.

An electromagnetic directional control valve VM as a main valve is connected to the hydraulic oil supply passage from the hydraulic power unit 210. When the electromagnetic directional control valve VM is in a non-excited state, the entire amount of hydraulic oil from the power unit 210 is stored in the reservoir 2
The pressure is returned to 17, and when the electromagnetic directional control valve VM is in the excited state, the pressure oil at the set pressure is supplied to the circuit. It is needless to say that the set pressure in this case is switched between high and low pressures according to the load pressure, the set pressure on the high pressure side is set by the relief valve 215, and the set pressure on the low pressure side is set by the unload valve 216. .

The pressure oil supplied from the electromagnetic direction switching valve VM is supplied to the electromagnetic direction switching valve VA for switching the direction of one hydraulic piston cylinder device 110 and the electromagnetic direction for switching the direction of the other hydraulic piston cylinder device 120. A switching valve VB;
It is led to a pressure reducing valve VR for adjusting the supply pressure to each of the hydraulic clamping devices 130 and 140. The pressure of the supplied pressure oil is measured by a pressure measuring device P1, and the clamp pressure reduced by the pressure reducing valve VR is measured by a pressure measuring device P2, and is displayed on a display unit attached to the housing surface of the control unit 200. It has become so.

Each load-side port of the solenoid-operated directional control valve VA has a flow control valve VF _AR and VF _AR with a check, respectively.
Connected to hydraulic ports 206 _AR and 206 _AH via _AH ,
The ports communicate with the rod-side cylinder chamber 114 and the head-side cylinder chamber 112 of the hydraulic piston cylinder device 110, respectively. In this case, when the electromagnetic directional control valve VA is in the non-excited state, the supply pressure oil is _reduced to the set flow rate by the flow control valve VF _AH and guided to the head side cylinder chamber 112 of the cylinder device 110, and the cylinder device 110 return fluid from the rod-side cylinder chamber 114 is returned to the reservoir 217 in a free flowing open the check of the flow control valve VF _AR. Conversely, solenoid directional control valve V
When A is in the excited state, the supply pressure oil is guided focused on set flow in the flow control valve VF _AR to the rod-side cylinder chamber 114 of the cylinder device 110,
The return oil from the head side cylinder chamber 112 of the cylinder device 110 is returned to the reservoir 217 by a free flow with the check of the flow control valve VF _AH opened.

Similarly, each load-side port of the electromagnetic directional switching valve VB is connected to a flow control valve VF with a check.
Hydraulic ports 206 _BR and 206 _BH are connected via _BR and VF _BH to the hydraulic piston cylinder device 1 from each port.
20 and communicate with the rod-side cylinder chamber 124 and the head-side cylinder chamber 122. In this case, when the electromagnetic directional control valve VB is in the non-excited state, the supply pressure oil is _reduced to the set flow rate by the flow control valve VF _BR and the cylinder device 12
In addition to being guided to the rod-side cylinder chamber 124, the return oil from the head-side cylinder chamber 122 of the cylinder device 120 returns to the reservoir 217 by free flow by opening the check of the flow control valve _VFBH , and conversely switches the electromagnetic direction. When the valve VB is in the excited state, the supply pressure oil is _reduced to a set flow rate by the flow control valve VF _BH and guided to the head side cylinder chamber 122 of the cylinder device 120, and the rod side cylinder chamber 124 of the cylinder device 120
The return oil from is returned to the reservoir 217 by free flow by opening the check of the flow control valve VF _BR .

The pressure reducing valve VR determines a clamping force, and reduces a part of the pressure oil supplied from the electromagnetic direction switching valve VM to a preset pressure to reduce the two electromagnetic direction switching valves Va.
And Vb. In this embodiment, these electromagnetic directional valves Va and Vb use a four-port two-position switching valve as an on-off valve. However, this may be replaced with a two-port two-position electromagnetic on-off valve.

The load-side port of one electromagnetic switching valve Va is
Hydraulic port 207 via throttle check valve VFa
a from the hydraulic port 207a to the clamp cylinder chamber 131 of one hydraulic clamp device 130 via a hydraulic hose. In this case, when the electromagnetic switching valve Va is in a non-excited state, the pressure oil depressurized by the pressure reducing valve VR is reduced to a set flow rate by the throttle check valve VFa and introduced into the clamp cylinder chamber 131. The speed is adjusted to the set value. On the other hand, when the electromagnetic switching valve Va is in the excited state,
The pressure oil from the pressure reducing valve VR is blocked, and the pressure oil returning from the clamp cylinder chamber 131 opens the throttle check valve VFa at a predetermined cracking pressure and returns to the reservoir 217.

The same applies to the other electromagnetic switching valve Vb. The load-side port is connected to the throttle check valve VFb.
Through the hydraulic port 207b, and from the hydraulic port 207b via a hydraulic hose to the clamp cylinder chamber 141 of the other hydraulic clamp device 140. In this case, when the electromagnetic switching valve Vb is in a non-excited state, the pressure oil depressurized by the pressure reducing valve VR is reduced to a set flow rate by the throttle check valve VFb, and the clamp cylinder chamber 1
41, whereby the clamping piston 143
Is adjusted to the set value. On the other hand, when the electromagnetic switching valve Vb is in the excited state, the pressure oil from the pressure reducing valve VR is blocked, and the pressure oil returning from the clamp cylinder chamber 141 opens the throttle check valve VFb at a predetermined cracking pressure to make the reservoir open. Reflux to 217.

The electric control circuit 220 converts the operation signal from the switch box 201 and the stroke end detection signal sent from each of the proximity switches S _A1 , S _A2 , S _B1 , S _B2 via the cable code C _C. An automatic switching device that controls the excitation switching of each of the electromagnetic switching valves VA, VB, Va, Vb, and VM based on one of two types of control modes as described later is built in. The control circuit 220 also includes a power supply opening / closing circuit for turning on / off the power supplied to the electric motor 211 based on a start-up operation signal from the switch box 201.

At the start of the tube removing operation, the operator operates the remote switch box 201 connected to the control unit 200 after connecting the core shaft 95 and setting the cylinder unit 100 as described above. To start the electric motor 211 and selectively operate the electromagnetic switching valves VM, Va, Vb, and
0, 120 and hydraulic clamping devices 130, 140 in FIG.
Set to the initial state as shown in. Here, the withdrawal speed of the extubation is determined by the flow control valves VF _AR and VF
_The setting is adjusted with _BH , and the return speed is adjusted with the flow control valves VF _AH and VF _BR . The clamping force is set and adjusted by the pressure reducing valve VR, and the speed at which each clamp piston is clamped is set and adjusted by the throttle check valves Va and Vb.

In the above initial state, the control device 220
When the first control mode is selected, the respective solenoid-operated switching valves VA, VB, V are switched at the same time as the excitation of the solenoid-operated switching valve VM by the switching timing with the opposite-phase operation cycle as shown in FIG. 6A.
When the second control mode is selected, the electromagnetic switching is performed simultaneously with the excitation of the electromagnetic switching valve VM and at the switching timing according to the in-phase operation cycle as shown in FIG. 6B. The valves VA, VB, Va, Vb are synchronously controlled to perform strong extubation.

That is, in the first control mode in which high-speed extubation is performed, as shown in FIG.
1, the electromagnetic switching valve VM is excited, and at the same time, the electromagnetic switching valve V
a is excited, and the pressurized oil of the pressure set by the pressure reducing valve VR is introduced into the clamp cylinder chamber 131, so that the collet chuck 133 of the hydraulic clamp device 130 clamps the core shaft 95, and upon completion of this clamp, When the delay time t1 set in the control circuit 20 elapses according to the required time, the electromagnetic switching valve VA is excited, and the adjusted amount of pressure oil is introduced into the rod-side cylinder chamber 114 of the hydraulic piston cylinder device 110. Then, the piston rod 111 moves in the pulling-out direction (rightward in FIG. 1) and starts pulling out the core shaft 95 and the pipe 92 connected thereto. Speed of the piston rod 111 in this case is limited to the value set by the flow control valve VF _AR, also during the withdrawal operation by the hydraulic piston cylinder device 110 is an electromagnetic switching valve VB and Vb is kept non-excited state ing.

At the time T2 when the piston rod 111 moves in the withdrawing direction and the magnet MA of the piston rod 111 is detected by the proximity switch S _A2 , the electromagnetic switching valves VA and Va are simultaneously switched to the non-excited state, and simultaneously the electromagnetic switching is performed. Valve Vb is switched to the excited state. As a result, in the hydraulic clamping device 130, the pressure in the clamp cylinder chamber 131 drops from the check of the throttle check valve VFa to the reservoir 217 through the electromagnetic switching valve Va, so that the clamping force to the collet chuck 133 is lost. Indicates that the pressure oil switched by the electromagnetic switching valve VA is supplied to the head side cylinder chamber 112 at the flow rate set by the flow control valve VF _AH and the return oil from the rod side cylinder chamber 114 is checked by the flow control valve VF _AR . , A free flow from the electromagnetic switching valve VA to the reservoir 217 can be performed, and the piston rod 111 released from the clamp with the core shaft 95 returns to the left in FIG. Return speed of the piston rod 111 in this case is limited to the flow rate set value in the flow control valve VF _AH.

The hydraulic piston cylinder device 11
When the electromagnetic switching valve Vb is switched to the energized state at the start time T2 of the return operation of 0, this causes the pressure reducing valve V to be transferred to the clamp cylinder chamber 141 of another hydraulic clamping device 140.
The pressure oil set at R is introduced, and the collet chuck 143 of the hydraulic clamping device 140 clamps the core shaft 95. When a delay time t2 set in the control circuit 20 has elapsed from the time T2 corresponding to the time required to complete the clamping, the electromagnetic switching valve VB is excited and the head side cylinder chamber 1 of the other hydraulic piston cylinder device 120 is excited.
The adjusted flow rate of the pressurized oil is introduced into 22, and the piston rod 121 moves in the pulling-out direction (rightward in FIG. 1) to pull out the core shaft 95 and the pipe 92 connected thereto. At this time, the speed of the piston rod 121 is limited to a value set by the flow control valve _VFBH , and during this pulling-out period, the electromagnetic switching valves VA and Va are kept in a non-excited state.

While the piston rod 121 is moving in the pulling-out direction, the piston rod 111 completes the return movement, and the control circuit 220 holds that the magnet MA is detected by the proximity switch S _A1 as a sequence operation condition. I have. Under the condition that the detection signal from the proximity switch S _A1 arrives, the piston rod 121 moves in the withdrawal direction and the magnet MB of the piston rod 121 moves.
Is detected by the proximity switch S _B2 , the time T
At 3, the electromagnetic switching valves VB and Vb are switched to the non-excited state,
At the same time, the electromagnetic switching valve Va is switched to the excited state. As a result, the pressurized oil of the pressure set by the pressure reducing valve VR is again introduced into the clamp cylinder chamber 131 of the hydraulic clamp device 130, so that the collet chuck 1 of the hydraulic clamp device 130
33, when the core shaft 95 or the tube 92 has been pulled out to some extent, the tube 92 is clamped instead, and when a delay time t1 set in the control circuit 220 has elapsed in accordance with the time required for completing the clamping. And the electromagnetic switching valve V
A is excited and the flow control valve VF is provided in the rod side cylinder chamber 114 of the hydraulic piston cylinder device 110.
The pressure oil at the flow rate adjusted by _AR is introduced, and the piston rod 111 moves again in the withdrawing direction to further withdraw the pipe 92.

On the other hand, at time T3, the electromagnetic switching valves VB and Vb
Is switched to the non-excitation state, the hydraulic clamping device 1
At 40, the pressure of the clamp cylinder chamber 141 drops from the check of the throttle check valve VFb to the reservoir 217 through the electromagnetic switching valve Vb.
43, the pressure oil switched by the electromagnetic switching valve VB is supplied to the hydraulic piston cylinder device 120 at a flow rate set by the flow control valve VF _BR to the rod-side cylinder chamber 124, and The return oil from the side cylinder chamber 122 flows freely through the check of the flow control valve VF _BH and the electromagnetic switching valve V
Since the fluid can be returned from b to the reservoir 217, the piston rod 121 released from the clamp with the pipe 92 returns to the left in FIG. Return speed of the piston rod 121 in this case is limited to the flow rate set value in the flow control valve VF _BR.

This return operation of the hydraulic piston cylinder device 120 is also completed while the piston rod 111 of one hydraulic piston cylinder device 110 is moving in the pulling-out direction.
The fact that B is detected by the proximity switch S _B1 is held as a sequence operation condition. This proximity switch S
Under the condition that the detection signal from _B1 has arrived, when the piston rod 111 moves in the withdrawing direction and the magnet MA of the piston rod 111 is detected by the proximity switch S _A2 , at time T4 the electromagnetic switching valve VA And Va are switched to the non-excited state, and at the same time, the electromagnetic switching valve Vb is switched to the excited state. As a result, the hydraulic clamping device 1 is again
Since the pressurized oil of the pressure set by the pressure reducing valve VR is introduced into the clamp cylinder chamber 141 of the hydraulic pump device 40, the hydraulic clamp device 14
The collet chuck 143 clamps the pipe 92 and the control circuit 22 adjusts the time required to complete the clamping.
When the delay time t2 set within 0 elapses, the electromagnetic switching valve VB is excited and the hydraulic piston cylinder device 12
The pressure oil at the flow rate adjusted by the flow control valve VF _BH is introduced into the head-side cylinder chamber 122 of No. 0, and the piston rod 121 moves in the withdrawing direction again to further withdraw the pipe 92.

[0120] The alternating negative-phase cyclic operation by the two hydraulic piston cylinder devices 110 and 120 as described above is repeatedly performed together with the alternating operation of the hydraulic clamp devices 130 and 140. In this case, one of the hydraulic piston cylinder devices is removed. Since the other hydraulic piston cylinder device performs the return operation during the operation, no time is wasted, and the entire length of the pipe 92 is removed at a relatively high speed. In the above description, it is desirable that the delay times t1 and t2 be the same delay time, but they need not always be the same.

In the present embodiment, when the entire length of the pipe 92 has been removed, the operator operates the switch box 201 to control the control circuit 2.
The operation of the cylinder unit 100 is suspended by giving a stop signal to the cylinder 20 and returning to the above-described initial state, and then the excitation of all the electromagnetic switching valves is stopped. In addition to the above, for example, a pressure sensor for detecting disappearance of the pull-out reaction force is attached to the support structure 101 of the unit 100 to use the detection signal, or a photo sensor for detecting that the end of the tube 92 has passed the collar 103. The automatic pause operation can also be achieved by using the detection signal and detecting the sudden decrease in the load pressure by the pressure measuring device P1 and using it.

When the removal of one pipe is completed in this way, the operator sets the core shaft 95 and the portable cylinder unit 100 to the next pipe to be removed and immediately operates the hand operation switch to continue the operation. It is possible to perform a tube removing operation, and by repeating this process for each tube, a large number of tubes can be successively hydraulically removed at high speed over the entire length.

The above is the control mode of the high-speed extubation by the opposite-phase cyclic operation of both hydraulic piston cylinder devices. However, the strong extubation which sums both the pulling forces by periodically operating both hydraulic piston cylinder devices in the same phase. Can be performed. That is, when the second control mode is selected by the control circuit 220, each of the electromagnetic switching valves VA, VB, Va, Vb is excited simultaneously with the electromagnetic switching valve VM and switched at the same timing as shown in FIG. Are synchronously controlled to perform strong extubation. In FIG. 6b, an electromagnetic switching valve V for switching the operating direction of both hydraulic piston cylinder devices
A and VB are synchronously controlled in phase, and correspondingly, the electromagnetic switching valve Va for switching the operation of both hydraulic clamping devices.
And Vb are also synchronously controlled in phase.

When the second control mode is selected, the control circuit 220 controls the excitation switching of each electromagnetic switching valve at the timing and polarity as shown in FIG. 6B based on the signal from each proximity switch. In this case, the withdrawal speed is reduced as compared to the first control mode, but the withdrawal force is increased twice as much as the withdrawal force of both hydraulic piston cylinder devices, for example, to forcibly withdraw a tube firmly fixed to the tube sheet. Sufficient power is obtained.

In this embodiment, the control circuit 220 determines the relative relationship between the polarities of the exciting currents of the respective solenoid-operated directional control valves in the circuit so that the first control mode and the second control mode can be selected. Not only is it configured to be switchable by operation, but also in the state where the tube 92 is fixed to the structure at the initial stage after the start of extubation, the second control mode is set, and the tube is pulled out by this second control mode. A switching device for automatically switching the control mode so as to select the first control mode after being released from the fixation to the structure is included.

This automatic switching device is constituted by a counter, a logic circuit and a switching relay circuit (not shown) in the control circuit 220. The automatic switching device is provided with a predetermined initial number of strokes from the time when the start command signal from the switch box 201 arrives. Controls each hydraulic piston cylinder device in the second control mode to perform strong extubation, and when the number of strokes of this strong extubation operation reaches the set value, automatically switches to the first control mode based on the counting result by the counter, The mode is automatically switched so that the remaining pipe length is removed at high speed until the pipe is completely removed.

Of course, this automatic switching method is not limited, and for example, a comparison with a reference value set and adjusted in advance based on a signal from a sensor for measuring the above-described load torque, drawing speed, pipe drawing amount, or the like. Thus, a method of automatically switching the mode from the second control mode to the first control mode can be adopted.

In this embodiment, the hydraulic power unit 21
Since 0 is switched between a high pressure small flow rate and a low pressure large flow rate according to the load, a low pressure large flow rate can be supplied at the time of a low load return operation in the strong control tube in the second control mode. It is possible to increase the set flow rate of the flow control valves VF _AH and VF _BR for setting the return operation speed of each of the hydraulic piston cylinder devices 110 and 120, to increase the return operation speed, and to shorten the return time not contributing to pulling out as much as possible. it can.

Further, in this embodiment, the flow control valves VF _AR and VF _BH are used as control valves for setting the drawing speed of each hydraulic piston cylinder device, but these valves are, for example, proportional solenoid flow control valves with checks. By applying an AC signal or a pulse signal of, for example, a triangular wave of several to several tens of Hz to the exciting current, additional hydraulic vibration is given to the supply pressure oil for the drawing operation to the hydraulic piston cylinder device. Which may oscillate the pulling force to reduce friction between the tube and the structure,
Pulling out can be facilitated.

[0130]

As described above, according to the tube removing apparatus according to the present invention, each of the movable portions of the first and second reciprocating devices is driven by the driving device so as to reciprocate repeatedly in synchronization with each other. Drive control is performed, and continuous extubation work on the extubation target tube can be performed by such synchronous repetitive driving, so the work time is extremely shortened, and work is efficiently performed when extruding many pipes one after another. Can be.

Further, the extubation device according to the present invention can extrude the entire length of the pipe by power continuously and repeatedly while being set in the target pipe. There is no need to perform extra work such as replacement or removal of the device.

In the tube removing apparatus of the present invention, continuous repetitive drawing operation can be alternately performed by operating the first and second reciprocating devices synchronously in opposite phases to each other. Can be pulled out at a relatively high speed.

Further, in the tube removing device of the present invention, the continuous repetitive drawing operation can be performed simultaneously by operating the first and second reciprocating devices synchronously in phase with each other. Can be pulled out with strong power.

Further, in the extubation device of the present invention, the phase of the synchronous operation of the first and second reciprocating devices can be selected to be the same phase or opposite phase, so that a relatively strong extubation and a relatively high-speed extubation can be achieved. In this case, high load is applied during extubation work.For example, strong extubation is performed at the initial stage, and high-speed extubation is performed at other relatively low loads. In accordance with this, it is possible to perform tube removal with a different drawing force and a different drawing speed, and it is possible to appropriately select one according to the state of embedding the tube and the progress of the work, so that the work efficiency is further improved.

Further, in the tube removing device of the present invention, the first and second reciprocating devices can each be constituted by a single-rod double-acting hydraulic piston-cylinder device, and these cylinder devices are connected to each other on the piston head side. By arranging the parts facing each other, the ends on the piston rod side of the two cylinder devices face outward, respectively, and by incorporating the force transmission mechanism into each outwardly facing piston rod, for example, to support maintenance or deformed pipes When the clamp portion of the force transmission mechanism is exchanged, there is an advantage that the device does not have to be disassembled. Such a feature that the consumable part or the part to be replaced according to the size of the target pipe is easily accessible from the outside can also reduce the time required for maintenance, thereby improving the efficiency of the pipe removal operation. be able to.

In the tube removing apparatus of the present invention, the entire length of the tube can be continuously removed, so that there is no need to use a winch or a forklift as another tube removing power, and the tube removing operation can be performed by one person.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a portable cylinder unit which is a main part of a tube removing apparatus according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an overall configuration of a tube removing device according to the embodiment.

FIG. 3 is an explanatory view exemplifying a shape of a core shaft which is used for assisting the extubation operation by the extubation device according to the embodiment, FIG. 3A is a side view in which a part of the length is omitted, and FIG. Fig. B is an enlarged view of a portion b, and Fig. C is an end view taken along the line cc of Fig. A.

FIG. 4 is an explanatory view showing a hydraulic clamp device as an example of a force transmission mechanism of the tube removing device according to the embodiment, wherein FIG. 4A is a rear view of the collet chuck viewed from the clamp piston side in the axial direction, and FIG. FIG. 2 is a cross-sectional view taken along line bb in FIG. 1 and FIG.

FIG. 5 is a hydraulic circuit diagram showing a configuration example of a hydraulic control unit used in combination with the portable cylinder unit of the embodiment.

FIG. 6 is a diagram exemplifying operation timings of a plurality of electromagnetic switching valves in a hydraulic control unit and a stroke detection proximity switch provided in a portable cylinder unit in the embodiment, and FIG. FIG. 6B is a timing chart at the time of high-speed extubation and at the time of strong extubation in the second control mode.

[Explanation of symbols]

91 Structure 92 Pipe 100 Portable Cylinder Unit 110 First Hydraulic Piston Cylinder Device (First Reciprocating Device) 120 Second Hydraulic Piston Cylinder Device (Second Reciprocating Device) 130 First Hydraulic Clamp Device ( First force transmission mechanism) 140 Second hydraulic clamping device (second force transmission mechanism) 200 Hydraulic control unit (drive device, control device)

Continuation of the front page (72) Inventor Toshiharu Tanaka 2410 Motoe, Uozu-shi, Toyama Pref. Inside Sugino Machine Co., Ltd. (56) References Japanese Utility Model Sho 63-177903 (JP, U) Japanese Utility Model Hei 2-6126 (JP, U) (58) Investigated field (Int. Cl. ⁷ , DB name) B23P 19/04 B23P 21/00 302 WPI / L (QUESTEL)

Claims (9)

(57) [Claims] 1. A tube removing apparatus for removing a tube from a structure by moving a tube fixed to the structure in an axial direction against a drawing reaction force acting between the tube and the structure. First and second reciprocating devices each having a movable portion that is arranged in tandem in the direction and that repeatedly reciprocates in the axial direction, and each movable portion of the first and second reciprocating devices and the pipe. A unidirectional first and second force transmission mechanism for preventing relative movement in the axial direction only when the movable portion moves in the tube withdrawing direction and transmitting a pulling force by the movable portion to the tube; A drive device for driving the first and second reciprocating devices so that each movable portion of the first and second reciprocating devices reciprocates repeatedly in synchronization with each other. apparatus. 2. The driving device according to claim 1, wherein one of the first and second reciprocating devices moves in the pulling-out direction so that the other of the first and second reciprocating devices returns in the opposite direction. 2. The tube removing device according to claim 1, further comprising a control device for synchronously operating the first and second reciprocating devices at operation phases opposite to each other. 3. The driving device according to claim 1, wherein the first and second reciprocating devices are moved in the same operation cycle so that each movable portion of the first and second reciprocating devices simultaneously moves in the same direction. The extubation device according to claim 1, further comprising a control device for performing a synchronous operation. 4. The driving device according to claim 1, wherein when one of the first and second reciprocating devices moves in the pulling-out direction, the other of the first and second reciprocating devices returns in the opposite direction. A first control mode in which the first and second reciprocating devices are synchronously operated with operation phases opposite to each other, and the movable portions of the first and second reciprocating devices are simultaneously moved in the same direction. 2. The extubation device according to claim 1, further comprising a control device capable of selectively switching between a first control mode and a second control mode in which the first and second reciprocating devices are synchronously operated at the same operation cycle. 5. The control device is in a second control mode when the pipe is fixed to the structure, and when the pipe is removed in the second control mode, the pipe is disengaged from the structure. The tube removing device according to claim 4, further comprising a switching device for automatically switching the control mode so as to select the first control mode after the switching. 6. The hydraulic piston cylinder according to claim 1, wherein said first and second reciprocating devices each include a single rod type double-acting hydraulic piston cylinder device, and said movable portion is constituted by a piston rod of each hydraulic piston cylinder device. The devices are arranged in tandem in opposite directions with their ends on the piston head side facing each other, and the force transmission mechanism is provided on a piston rod of each of the hydraulic piston cylinder devices. 2. The extubation device according to 1. 7. The first and second reciprocating devices each include a double-acting hydraulic piston-cylinder device, the movable portion is constituted by a piston rod of each hydraulic piston-cylinder device, and the movable portion is moved in the pulling-out direction. The tube removing device according to claim 1, wherein the piston receiving pressure areas of the hydraulic piston cylinder devices contributing to the movement of the pipes are configured to be equal to each other. 8. A tube removing device for removing a tube from the structure by moving a tube fixed to the structure in the axial direction against a drawing reaction force acting between the tube and the structure. First and second double-acting hydraulics having a hollow structure that has a piston rod that is arranged in tandem in the direction and that repeatedly reciprocates with a predetermined stroke in the axial direction, and that allows passage of the pipe in the axial direction. A piston-cylinder device, a portable supporting structure that integrally holds the first and second hydraulic piston-cylinder devices and that can abut against the structure to support the pull-out reaction force; And the second hydraulic piston-cylinder device is provided on each piston rod, and only when the piston rod moves in the tube withdrawing direction, First and second hydraulic clamping devices that clamp by a pressure operation force and transmit the pulling force of the piston rod to the pipe; and the first and second hydraulic clamping devices based on hydraulic oil supplied from a power-driven hydraulic pump. A tube removing device comprising: a second hydraulic piston cylinder device; and a hydraulic drive control device that synchronously controls the first and second hydraulic clamp devices at a predetermined operation phase cycle. 9. The hydraulic drive control device according to claim 1, wherein one or both of the first and second hydraulic piston and cylinder devices are provided with means for applying vibration to hydraulic pressure for moving the piston rod in the withdrawal direction. The tube removing device according to claim 8, wherein the tube removing device is provided.