JPH0659849B2 - Moving device in circular pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention mounts a fiberscope and moves in a circular pipe,
The present invention relates to a moving device in a circular pipe used for investigating the condition inside the pipe.

<Prior art and its problems> Since the heating furnace used in the petrochemical industry is in a high temperature environment in the heating pipe, caulking (baking) of the raw material on the inner surface of the pipe
Hair cracks due to heat stress may occur.

As a method for inspecting this, regarding the coking state of the raw material, (1) the pressure at the heating furnace inlet / outlet is checked during operation.

(2) During operation, measure the outer surface of the pipe with an infrared thermometer and infer from it.

(3) During shut down, check the caulking state using X-rays.

However, for (1) and (2), the location and measurement are indirect, and for (3), measuring all tubes is time-consuming and costly.

Therefore, a method of inserting a fiberscope into the tube and checking it can be considered.

Since the inside of the tube can be directly viewed with the fiberscope,
Not only caulking but also hair cracks can be inspected. And if the pipe is a bent pipe or the space on the inlet side of the pipe is narrow, it cannot be inserted into the pipe by attaching it to a long rigid rod with a fiberscope, so insert only the flexible tube of the fiberscope itself into the pipe. However, when inserting into the heating tube from below, it is unknown whether the flexible tube is straight in the heating tube or which direction the tip is facing, and therefore the position and direction of the tip are specified. Is difficult to locate, and therefore the location of the defect is difficult to locate.

In order to solve the above problems, the advent of a device or robot that moves in a pipe is desired, and a wall surface robot having a vacuum suction pad (Japanese Patent Application No. 58-93949) and a magnet type wall robot (Japanese Patent Application No. 58-187036). It is also possible to use such as.
However, such a robot has a problem that the shape is too large to move in a 6 to 8 inch pipe, it cannot be used in the case of a pipe made of a material that does not attract a magnet, and the mechanism is complicated and expensive. Not practical.

<Objects of the Invention> The present invention has been devised in view of the above problems of the prior art, and is capable of moving in a heating pipe having a diameter of 4 to 10 inches by a simple mechanism using compressed air and having an excellent gripping force. It is an object of the present invention to provide a moving device in a circular tube having a.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the circular pipe moving device of the present invention is a leg made of an elastic body that can be stretched by being supplied with a pressure fluid inside and pressed against the inner peripheral surface of the pipe. A pair of legs having at least three bellows feet each having a tip in the radial direction, and a pair of legs arranged between the pair of legs and connected to the center of each leg by supplying a pressure fluid. A bellows body that extends and contracts by discharge, and a control device that separately supplies and discharges pressure fluid to each leg and body, and is provided with a circular pipe moving device. It is what

<Embodiment> A preferred embodiment of the present invention will be described below with reference to the drawings. First
The drawing is a side view of the moving device in a circular pipe of the present invention, and FIG.
It is a II-II arrow line view of a figure. In FIGS. 1 and 2. 1
Is the rear leg. 1a is the center of the leg, the air supply port 1d
Is a passage for sending compressed air to the three bellows legs 1b and 3b extending in the radial direction, and the three bellows legs 1b and 3b are separately pressurized. The bellows is made of a thin plate such as hard rubber or bronze.

1c is the tip of the foot, which is made of rubber and has a substantially spherical shape. When the legs 1b are stretched, the inner tips of the legs are evenly pressed by the leg tips 1c of the three legs, and the rear leg 1 is fixed in the pipe. -It works to hold. Reference numeral 2 denotes a bellows body, which is made of a thin plate of hard rubber or bronze, and has a tension coil spring 2a provided inside.
The compressed air is supplied from the air supply port 2b to expand, and the compressed air inside is discharged to contract.

Reference numeral 3 denotes a front leg portion, which has the same structure as the rear leg portion 1 and includes a center portion 3a, a foot 3b, a foot tip portion 3c, and an air supply port 3d. The bellows feet 1b, 3b and the body 2 are connected via a solenoid type switching valve 5a, 5b, 5c by a tank 6 which stores compressed air which is a fluid pressure supply source and a rubber hose 4 which supplies compressed air. Each of the switching valves 5a, 5b, 5c is constructed so that it can independently send compressed air to the bellows feet 1b, 3b and the body 2 or discharge compressed air from the control panel 7. There is.

Next, the operation will be described. First, the case of moving forward will be described step by step.

(1) If the switching leg 5a is in a state where the rear leg 1 and the compressed air tank 6 are in communication with each other, and compressed air is sent to the rear leg 1,
1b stretches and presses the foot tip 1c against the inner surface of the tube,
Is fixed in the tube.

(2) With the rear leg 1 fixed, the switching valve 5b is brought into communication with the body 2 and the compressed air tank 6, and compressed air is sent to the body 2. The front leg 3 is extended and is advanced.

(3) With the rear leg portion 1 fixed and the trunk portion 2 extended, the switching valve 5c is brought into communication with the front leg portion 3 and the compressed air tank 6, and compressed air is sent to the front leg portion 3. Then, the foot 3b extends and presses the tip 3c of the foot against the inner peripheral surface of the tube, and the front leg 3 is fixed in the tube.

(4) With the front leg 3 fixed, the switching valves 5a, 5b
When the compressed air is released from each bellows in such a manner that the bellows of the rear leg portion 1 and the body portion 2 communicate with the atmosphere, the bellows of the body portion 2 and the rear leg portion 1 contract, and The side leg 1 is pulled toward the front leg 3 and moves forward.

(5) While the front leg 3 is still fixed, compressed air is sent to the rear leg 1 to fix the rear leg 1 in the pipe.

(6) After the rear leg 1 is fixed in the pipe, the compressed air in the front leg 3 is released to the atmosphere.

(7) By repeating the operations from (2) to (6), the moving device in the circular pipe of the present invention advances.

When moving backward, the operation may be performed in the reverse order.

<Modifications> The present invention is not limited to the above-mentioned embodiments, and the following modifications included in the scope of claims are possible.

(1) Coil spring inside the bellows when the contraction force of the bellows of the body 2 is large enough when compressed air is released.
2a is optional.

(2) The fluid used for expanding and contracting the bellows is not limited to compressed air and may be pressure water or pressure oil.

<Effects of the Invention> As described above, the moving device in a circular pipe of the present invention has the following effects.

(1) Since it has a simple structure in which several bellows are combined, it is inexpensive, has few failures, and moves reliably.

(2) Since the body bellows is flexible with respect to bending, it can move freely even inside a bent circular pipe.

(3) If a sequence controller or a mini computer incorporating a simple program is built into the control panel, simply send forward, stop, and reverse command signals, and the control panel will automatically switch the solenoid type switching valve in sequence. As the device is moved to move the device, the operation becomes easy.

(4) If a throttle valve is provided in the middle of the passage for sending the compressed air to each bellows and the flow rate of the compressed air is adjusted, the forward or backward speed can be changed.

(5) Since the pressed state and the released state of the legs are clearly distinguished, and the front and rear pressure / release states can be freely selected,
You can move forward and backward freely, and there is little resistance to movement. In addition, since the fluid supply / discharge time in the body bellows can be shortened, the movement cycle can be shortened.

(6) Since the tip of the foot is made of an elastic material, the bellows does not directly contact the inner surface of the pipe, and even if there is a sharp protrusion, the bellows is not damaged.

[Brief description of drawings]

FIG. 1 is a drawing combining a side view and an operation system diagram of a moving device in a circular pipe of the present invention, and FIG. 1 …… Rear leg 1b …… Bellows foot 2 …… Body 3 …… Front leg 3b …… Bellows foot

Claims (1)

[Claims] 1. A pair of at least three bellows feet in the radial direction, each of which has a bellows foot having an elastic foot end that can be stretched by being supplied with a pressure fluid and pressed against the inner peripheral surface of the tube. A leg portion and a pair of leg portions are disposed between the leg portion and the center of each leg portion, and are extended by supplying a pressure fluid,
An apparatus for moving in a circular pipe, comprising: a bellows body that contracts due to discharge, and a control device that separately supplies and discharges pressure fluid to each leg and body.