JPS6356013B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to expanding the tube end of a device in which a large number of tubes are arranged on one plane, such as a transfer tube of a heat exchanger fixed to a tube sheet, This invention relates to a sizing device that forms a uniformly shaped hole into which a plug is inserted at a constant depth.

In the case of a heat exchanger as shown in FIG. 1, a large number of U-shaped thin tubes 4 are connected to a hemispherical lower water chamber 2 of a cylindrical shell 1 partitioned by a tube plate 3 and a partition wall 5, which are fixed to the tube plate 3. The structure is such that one fluid flows inside the tube and the other fluid flows around the thin tube 4 to perform heat exchange. The tube 4 of this heat exchanger is
If there is a risk of fluid leakage, such as when a pinhole occurs, a blind plug may be installed to prevent this. In this plug method, welding plugs are often used due to their high reliability, but it is important to maintain the same insertion depth and welding conditions, so the opening end of the capillary is set to a certain size and shape. It is necessary to form the hole in advance. However, this plug hole forming process requires automation and remote control since it is difficult for the operator to enter and requires an upward position which is easily tiring.

An object of the present invention is to provide a welding sizing tool that can automatically form a hole for press-fitting a blind plug into a pipe material by remote control.

The structure of the present invention that achieves this object is such that a taper roller that contacts the inner circumferential surface of a pipe to be processed and a tube expansion mandrel inserted between the taper rollers are held movably in the axial direction by a spring, and the mandrel is A sizing processing section connected to a drive source via a flexible joint and a spline, and an anchor block provided with a clamp shaft inserted and fixed into a pipe adjacent to the to-be-processed pipe are connected via an elastic member; The present invention is characterized in that the sizing processing section is attached to a movable frame of the elevating section that is attached to the guide device via an attachment.

The configuration of the present invention will be explained in detail below based on a specific example shown in the drawings. In addition, in this specific example, the thin tube 4 is fixed in the vertical direction with the horizontal tube plate 3, and the cylindrical shell 1 is
This device is configured as a device for forming a hole for attaching a blind plug to the capillary tube 4 of a heat exchanger whose tube end faces into the hemispherical lower water chamber 2 of the heat exchanger.
In such a heat exchanger, it is difficult for an operator to enter and work inside the heat exchanger.

This device includes a sizing processing unit 8 that includes an expander 6, its drive source 7, and a drive device, a clamp shaft 9 that fixes the sizing processing unit 8 to the tube plate 3 during pipe expansion work, and a sizing processing unit 8 that An elevating section 10 for elevating and lowering, an attachment section 11 for attaching the elevating section 10 to a guide device 12, and the sizing processing section 8 below the thin tube 4 which is the tube to be processed.
It mainly consists of a guide device 12 that guides the user.

The guide device 12 is a so-called manipulator. The manipulator 12 is connected to the manhole 1
Fixed base 14 installed in 3 and support ball 1 in water chamber 2
A swivel base 18 is provided on a pedestal 17 fixed by 5 and support arms 16, and a main arm 20 that is tilted by an elevation arm 19 is mounted on the swivel base 18. Therefore, it can move freely within the spherical water chamber 2. Further, a swinging mechanism is attached to the tip of the main arm 20, which is extendable and pivotable, and a small arm 21 is also swingably installed via this swinging mechanism. This small arm 21 moves the lifting section 10 to the manipulator 12.
This constitutes an attachment section 11 that allows connection to be made with one operation. As the guide device, a walking robot that moves along the hanging tube plate 3 using holes in the thin tubes 4 fixed to the ceiling tube plate 3 can also be adopted.

As shown in FIG. 3, the attachment section 11 has a semi-cylindrical holding frame 23 formed on a small arm 21 whose mounting hole 22 is bolted to the vertical pivot axis of the swinging mechanism section of the manipulator. Two key grooves 24 are bored in the inner surface of the holding frame 23 in the longitudinal direction, and a lock plate 25 that can freely protrude inward of the holding frame 23 is provided. The attachment part 11 of this embodiment does not have a connecting function by itself, but the attachment part 1
A connecting function is achieved between the two rows of guide keys 26 formed on the side of the lifting section 10 connected to the lock plate 1 and the recess 27 into which the lock plate 25 is fitted. The lower end of the lock plate 25 is rotatably attached to the holding frame 23 of the small arm 21 with a pin 28.
The upper part of the small arm 21 is biased by a spring-loaded piston 29 built into the small arm 21, and is provided so as to always protrude inward of the holding frame 23. This lock plate 25 is always projected by the force of the spring 30, but as the lifting block 31 is inserted, it is pushed in until it engages with the recess 27 (see FIG. 4a). When locked, the piston 29 is moved by the air pressure introduced into the cylinder,
Fix the lock plate 25 in the protruding state (fourth
(see figure b). On the other hand, the recess 27 on the elevating part 10 side into which the lock plate 25 fits can be formed directly on the elevating part block 31, but in the case of this embodiment, it is formed as a separate member and then embedded. There is. Further, a relief groove 32 is provided near the keyway 24.
is provided. This escape groove 32
This is for passing the guide key 26 of the lifting part block 31 when removing the 0, and is connected to the key groove 24 at a portion by a bypass (not shown). The bypass is for enabling the lifting part block 31 to be twisted when the guide key 26 is located in the keyway 24, and the lower guide when the lifting part 10 is pushed more forcefully from the engaged state. It is drilled at the key 26 position. Therefore, by releasing the pneumatic air lock and pushing the engaged lock plate 25 further, pushing up and lowering the lifting block 31 even more strongly and then twisting it, the engagement between the key groove 24 and the guide key 26 is released and the recess 27 is released. This will cause the lock plate 25 to shift.
can be easily removed without any scratches. The lock plate 25 and the recess 27 are wedge-shaped in order to increase the tightening force when engaged.

The elevating part 10 is provided with a guide key 26 and a recess 27 that engage with the keyway 24 and lock plate 25 of the attachment part 11. 33 is built-in. The movable frame 33 is
It is supported by two guide rods 34 and connected by a ball feed screw 36 to a holder 35 that moves up and down. The moving frame 33 is raised and lowered by a lifting motor 37.
This is achieved by converting the rotation of the holder 35 into the vertical movement of the holder 35 meshed with the gears 38, 39 and the ball screw 36. The holder 35 is equipped with a magnet 40, which constitutes a limit switch for detecting an overrun of the movable frame 33 between the magnet 40 and the magnetic sensors 41a and 41b provided at the upper and lower ends. Further, a magnet 42 is intermittently attached to a gear 39 connected to the ball screw 36, and a magnetic sensor 43 that detects the magnet 42 measures the rotational speed of the ball screw 36 as well as the amount of elevation. It is provided.

The sizing processing section 8, which is fixed by being fitted into the mounting groove 44 of the movable frame 33, is inserted between the rotary roller 46 and the tapered roller 45, which incorporates a plurality of tapered rollers 45 that come into contact with the inner peripheral surface of the pipe to be processed 4. The expander 6 is mainly composed of an expander 6 including a mandrel 47 that transmits rotation and expands the diameter thereof, a drive source 7, and a drive device.
A mandrel 47, which is pushed between a plurality of tapered rollers 45 held by a retainer, is rotatably housed in a saucer-shaped cover 48. and,
The cover 48 is supported within the holding block 50 by a spring 49, and supports the mandrel 47 so that the mandrel 47 can be displaced in the vertical direction, that is, in the direction of the center of the tube 4 to be processed. Said mandrel 4
A spline shaft 52 is connected to 7 via a flexible joint, such as an Oldham joint 51. In addition, a torque limiter 54 is interposed in the spline sleeve 53 that fits on the spline shaft 52, and the gear 5
5 and 56 are connected. Therefore, the rotation of the air motor 7, which is the driving source, is caused by the following steps: gears 55, 56 → torque limiter 54 → spline sleeve 53 → spline shaft 52 → Oldham joint 51 → mandrel 4.
7 is transmitted. Thus, radial vibrations and displacements occurring in the mandrel 47 are absorbed by the Oldham joint 51, and axial vibrations and displacements are absorbed by the splines 52 and 5.
3, so it is not transmitted to the holding block 50 and eventually to the manipulator 12 side. A bearing 5 is attached to the lower end of the spline shaft 52 by a piston rod 58 of a cylinder 57 for lifting and lowering the mandrel.
They are rotatably connected via 9. Therefore, the operation of the air cylinder 57 causes the spline shaft 52 and, in turn, the mandrel 47 to move up and down. still,
A magnet 60 is attached to the piston rod 58, and constitutes a limit switch that detects overline of the piston rod 58 with magnetic sensors 61a and 61b installed at the upper and lower ends of the cylinder.

On the other hand, an anchor block 63 is connected to the holding block 50 via an elastic member such as a rubber damper 62. The anchor block 63 is a cylinder that movably accommodates the clamp shaft 9 that fixes the holding block 50 of the sizing processing section 8. A spring 64 is interposed between the anchor block 63 and the clamp shaft 9 to make the clamp shaft 9 elastic in the axial direction. support. Clamp shaft 9
At the tip of the clamp shaft 9, there are provided several clamp claws 66 that extend and retract in the radial direction as the tapered shaft 65 within the clamp shaft 9 moves in the axial direction. This clamp claw 6
6 has an elastic ring 67 applied to its outer surface to prevent it from coming off, and is brought into close contact with the inner tapered shaft 65. The lower end of the tapered shaft 65 is a piston 68 , and its descending side communicates with the supply hole 69 and its ascending side communicates with the supply hole 70 . A magnet 71 is attached to the spline shaft 9, and an anchor block 63 is attached to the spline shaft 9.
This constitutes a switch that indicates that insertion is not possible between the magnetic sensor 72 and the magnetic sensor 72 installed in the holder. That is, the clamp shaft 9 that rises together with the sizing processing section 8 is connected to the pipe 4.
When the clamp shaft 9 is not inserted inside, the clamp shaft 9 is relatively lowered while compressing the spring 64, and this is notified when the magnet 71 and the magnetic sensor 72 are opposed to each other.

Using the sizing device constructed as described above, the tube end diameter expansion treatment of the thin tubes of the heat exchanger is carried out as follows.

First, the manipulator 12 installed in the water chamber 2
The tip of the main arm 20, that is, the attachment part 11, is moved to just above the manhole 13, and the elevating part 10 to which the sizing processing part 8 is attached is attached. To install it, connect the elevating part 10 to the attachment part 1.
This is done by aligning the keyway 24 and the guide key 26 from below and then inserting them. The rotation of the lift block 31 is restricted by the guide key 26, so if the lift block 31 is pushed up in this state, the lock plate 25 is pushed in and can be inserted smoothly until the lock plate 25 and the recess 27 engage. (See Figure 4a). After the lock plate 25 and the recess 27 are engaged at a predetermined position, air pressure is applied to the cylinder to force the piston 29 against the lock plate 25 and completely fix them together (see FIG. 4b).

After the sizing processing unit 8 is attached to the manipulator 12, the main arm 20 is rotated, extended and raised to guide its tip to an arbitrary position within the water chamber 2, that is, below the pipe 4 that requires processing. Here, the posture of the tool can be corrected by swinging the tool, and by this correction, the tool posture can be maintained at a constant posture (perpendicular to the tube plate 3) (perpendicular to the surface of the tube plate 3). That is, the sizing tool can be guided completely remotely to the required position and in the required posture.

After the expander 6 and the clamp shaft 9 are positioned under a predetermined pipe 4 to be processed, the movable frame 33 of the elevating section 10 is raised and lowered to insert the rotating roller 46 and the clamp shaft 9 into the pipe 4. The movable frame 33 is raised by converting the rotation of the lifting motor 37 into the lifting movement of the holder 35 by means of the ball screw 36. The amount of elevation is obtained by multiplying the pulse generated by the combination of the magnet 42 and the magnetic sensor 43 by the lead of the ball screw 36. Further, overrun is prevented by stopping the lifting motor 37 by operating the limit switches 41a and 41b at the upper and lower ends.

The cylinder 57 is actuated to insert the mandrel 47 into the rotating roller 46 guided into the tube to be processed 4 as the movable frame 33 rises. The rotation of the air motor 37 is caused by gears 56, 55 → torque limiter 54 → spline sleeve 53 → spline shaft 5.
2→Transmitted to the mandrel 47 via the Oldham joint 51. Therefore, the tapered roller 45 rolling on the inner surface of the tube expands its ring while being rotated by the tapered mandrel 47, so that the rotating roller 4
The pipe diameter can be expanded to a maximum diameter of 6. The vibrations generated at this time are caused by the expansion and contraction of the spring 49, the splines 52, 5
While the axial component is absorbed by the action of 3, the radial component is absorbed by the Oldham joint 51, so vibrations are not transmitted to the manipulator 12 side and do not interfere with rotation transmission. On the other hand, the clamp shaft 9
The tube also rises together with the expander 6 and is inserted into the adjacent tube hole 4. Therefore, pressurized air is introduced from the supply hole 69 to pull down the tapered shaft 65, and the clamp claw 66, together with the elastic ring 67, is expanded and brought into close contact with the inner surface of the tube. With this clamp, the anchor block 63, the sizing processing section 8, the lifting section 1
Fix 0. Then, the vibrations (chattering vibrations, etc.) that could not be absorbed by the support of the Oldham joint 51 and the spring 49 are absorbed by the rubber damper 62, and the lifting part 10
In other words, any negative influence on the manipulator 12 is completely eliminated. In the unlikely event that the clamp shaft 9 cannot be inserted, the clamp shaft 9 compresses the spring 64, so that the vertical movement itself does not have an adverse effect. However, since the magnet 71 faces the magnetic sensor 72, it is possible to know from this signal whether insertion is not possible.

After the sizing process is completed, the blind plug is press-fitted. At this time, the main arm 20 is operated to return its tip to the manhole 13 and the elevating section 10 is inserted.
Remove the sizing processing section 8 from the. First, the pressure is released from the cylinder of the small arm 21 portion, and the tool/elevating section block 31 is further pushed up with a stronger force than when it was inserted. Then, the lock plate 25 is again connected to the spring 3.
0, rotates around the pin 28, and the recess 27
Get out of. If the lifting part block 31 is rotated in this state, the guide key 26 will move to the escape groove 32, so the lifting part 10 and the sizing processing part 8 can be pulled out from the attachment part 11 without being affected by the lock plate 25. .

In this way, according to the sizing tool of the present invention, it is possible to uniformly expand the end portion of a tube material to a required size. Furthermore, since it can be made small and lightweight, it can be mounted on a remote guidance device. Therefore, the operation is completely remote, the working environment can be greatly improved, and plug welding can be automated.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a working state in which sizing is performed on heat exchanger tubes, FIG. 2 is an assembled perspective view of a sizing tool according to the present invention, FIG. 3 is an exploded perspective view of the same, and FIG. Figures a to c are explanatory diagrams showing the engagement operation between the lock plate and the recess, Figure 5 is a central longitudinal cross-sectional view showing the structure of the sizing processing section, Figure 6 is a central longitudinal cross-sectional view showing the structure of the elevating section, FIG. 7 is a central vertical sectional view showing the structure of the clamp shaft. In the drawing, 4 is a thin tube, 6 is an expander, 8 is a sizing processing section, 9 is a clamp shaft, 10 is a lifting section, 11 is an attachment section, 12 is a guide device,
33 is a movable frame, 45 is a taper roller, 47 is a mandrel, 48 is a cover, 49 is a spring, 51 is an Oldham vertical arm (flexible joint), 52 and 53 are a spline shaft and a spline sleeve forming a spline vertical arm, and 57 is a mandrel lifting/lowering 62 is a rubber damper (elastic member), and 63 is an anchor block.

Claims (1)

[Claims] 1. A taper roller that contacts the inner peripheral surface of the pipe to be processed and a tube expansion mandrel inserted between the taper rollers are held movably in the axial direction by a spring, and the mandrel is connected to a drive source via a flexible shaft joint and a spline. The sizing processing section connected to the anchor block having a clamp shaft inserted into and fixed to the pipe adjacent to the to-be-processed pipe is connected via an elastic member, and the elevating section is attached to the guide device via an attachment. A sizing tool for welding, characterized in that the sizing processing section is attached to a movable frame.