JPH0741589Y2 - Pipe weld cooling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a pipe welded portion cooling device used in a water cooling welding method.

[Prior Art] Generally, when there is residual stress during welding, stress corrosion cracking easily occurs, so the water cooling welding (HSW) method is adopted as a measure to prevent stress corrosion cracking (SSC) during welding.

For example, when explaining a water-cooling welding method for welding a branch pipe to a main pipe as an example, a branch pipe provided with a groove is prepared and a through hole is formed in a main pipe radial direction at a branch pipe welding portion of the main pipe in advance. Set the branch pipe at the branch pipe welding point of the main pipe, and lightly weld the root part of the welding groove further so that cooling water does not leak from the gap between the branch pipe and the main pipe. , A pipe having a diameter that can be inserted into the branch pipe in order to supply the cooling water for cooling the weld part to the inside of the branch pipe when the subsequent welding is performed, and the pipe circumferential direction near the tip end A cooling water supply pipe having a plurality of small holes is inserted from the tip of the branch pipe toward the welded portion in the branch pipe, and the cooling water supply pipe is provided with a flange so as to be substantially concentric with the branch pipe. Fix the water supply pipe to the branch pipe.

Thus, when the cooling water is supplied to the cooling water supply pipe, the cooling water flows out from the small hole at the tip of the cooling water supply pipe into the branch pipe, and the gap between the inner peripheral surface of the branch pipe and the outer peripheral surface of the cooling water supply pipe is formed. It flows and flows out into the main pipe, during which the welded portion between the main pipe and the branch pipe is cooled from the inner peripheral surface side of the branch pipe.

[Problems to be Solved by the Invention] However, it is difficult to collect the cooling water that has flowed out of the branch pipe into the main pipe with the above-described pipe welding portion cooling means, and
For example, in the case of repair work on nuclear pressure vessel piping after operation, if cooling water leaks into the main pipe, it may be contaminated by radioactivity, so it cannot be circulated and a large amount of cooling water is required. Since the flow velocity of the water varies depending on the inner diameter of the branch pipe and the outer diameter of the cooling water supply pipe, it is difficult to keep the cooling water flow velocity (0.05M / S or more) specified by the water cooling welding (HSW) method. was there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a pipe welded portion cooling device which can circulate and use cooling water and can keep the flow velocity of cooling water above a prescribed level.

[Means for Solving the Problem] The present invention provides a pipe weld cooling device for cooling a main pipe and a welded portion of a branch pipe to be welded to an outer peripheral portion of the main pipe with cooling water. A cooling water supply pipe insertable into a branch pipe communicating with a through hole formed from the outer peripheral side to the inner peripheral side of the main pipe, and the cooling water supply pipe fitted on the cooling water supply pipe and A first sealing device that can be fitted in the through hole and that prevents cooling water from leaking from the branch pipe side to the main pipe side, and can be fitted to the cooling water supply pipe and fitted inside the branch pipe And a second sealing device that prevents the cooling water from leaking from the branch pipe to the outside, and a second sealing device that is installed on the branch pipe side of the first sealing device substantially concentrically to the cooling water supply pipe. A sleeve that forms a predetermined gap through which cooling water flows between the first sealing device and the inner peripheral surface of the welded portion. And a cooling water recovery pipe for collecting the cooling water that has passed through the gap, the sleeve being arranged so as to surround a small hole for circulating cooling water provided in the cooling water supply pipe, and the first sleeve of the sleeve. The end on the sealing device side is located closer to the first sealing device than the welded part, and a cover plate is attached to the end of the sleeve opposite to the first sealing device so that cooling water does not flow. It is a thing.

[Operation] Therefore, in the present invention, the cooling water supplied to the cooling water supply pipe flows out of the cooling water supply pipe through the small holes, and the sleeve and the first
Through the gap between the inner peripheral surface of the weld and the sleeve, and flows through the gap to the side of the second sealing device, so that the entire amount of cooling water is It passes through the inner peripheral surface of the weld, and therefore the weld is efficiently cooled from the inner peripheral surface of the branch pipe.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention.

A plurality of small holes 3 for communicating the inner and outer circumferences of the cooling water supply pipe 1 are bored at required positions in the longitudinal direction of the cooling water supply pipe 1 with the receiving plate 2 fixed to the lower end in the circumferential direction. Seal rubber plates 4a, 4b having a smaller diameter than the inner diameter of the branch pipe 5 and the inner diameter of the through hole 7 of the main pipe 6 whose outer diameter is welded to the cooling water supply pipe 1 and larger than the outer diameter of the receiving plate 2. The lower seal rubber plate 4b
The lower surface of the seal plate 4b is supported on the upper surface of the receiving plate 2, and the seal rubber plate 4b
It is fitted so that the lower surface of the seal rubber plate 4a is supported on the upper surface of the.

The seal rubber plates 4a, 4b are tapered at the upper and lower outer circumferences thereof, and the upper and lower faces of the seal rubber plates 4a, 4b are provided with recesses 8 substantially concentric with the outer diameters of the seal rubber plates 4a, 4b. And the first sealing device 4 by the sealing rubber plates 4a and 4b.
Are formed.

On the upper surface of the seal rubber plate 4a, a pressing plate 9 fitted on the cooling water supply pipe 1 and having an outer diameter substantially the same as that of the receiving plate 2 is provided below the small hole 3 provided in the cooling water supply pipe 1. Place it on the side.

A plurality of small holes 10 for communicating the inner and outer peripheral portions at a required interval in the circumferential direction at the lower end are bored so as to have substantially the same height as the small holes 3 and have a shorter length than the cooling water supply pipe 1. Spacer
11 is fitted onto the cooling water supply pipe 1 to fix the lower end of the spacer 11 to the pressing plate 9, and the outer periphery of the lower end of the spacer 11 is
A sleeve 12 formed by a cover plate 12a and a sleeve body 12b is attached so as to surround the small hole 10.

That is, the disk-shaped lid plate 12a is fixed to the spacer 11 so as to be located above the small hole 10, and the lower end is located above the lower end of the spacer 11 on the outer peripheral portion of the lid plate 12a. The cylindrical sleeve body 12b is fixed so that a gap H is formed between the sleeve 9 and the plate 9. The outer diameter of the sleeve body 12b is such that a desired gap S is formed between the inner circumference of the branch pipe 5 and the inner circumference of the through hole 7 formed in the main pipe 6 when the device is set in the branch pipe 5. To do.

The receiving plate 13 is fitted onto the cooling water supply pipe 1 and fixed to the upper end of the spacer 11 so that the cooling water supply pipe 1 has an outer diameter smaller than the inner diameter of the branch pipe 5 and is received. The seal rubber plates 14a, 14b having a diameter larger than the outer diameter of the plate 13 are supported such that the lower surface of the lower seal rubber plate 14b is supported by the upper surface of the receiving plate 13 and the lower surface of the seal rubber plate 14a is supported by the upper surface of the seal rubber plate 14b. The cover plate 15 having an outer diameter larger than the inner diameter of the branch pipe 5 is externally fitted to the cooling water supply pipe 1, and the cover plate 15 is brought into contact with the upper surface of the seal rubber plate 14a.

The upper and lower outer circumferences of the seal rubber plates 14a, 14b are tapered, and the upper and lower facing surfaces of the seal rubber plates 14a, 14b are provided with recesses 16 substantially concentric with the outer circumferences of the seal rubber plates 14a, 14b. A second sealing device 14 is formed by the sealing rubber plates 14a and 14b.

A short spacer 17 is externally fitted to the cooling water supply pipe 1, the lower end of the spacer 17 is fixed to the upper surface of the lid plate 15, and a seat plate 18 externally fitted to the cooling water supply pipe 1 is fixed to the upper end of the spacer 17. The wing nut 20 is attached to the threaded portion 19 that is screwed around the upper end of the cooling water supply pipe 1.
Are screwed so that the lower surface contacts the seat plate 18.

The cooling water recovery pipe 21 is inserted such that the cover plate 15 and the seal rubber plates 14a, 14b pass through the receiving plate 13 side by side, the lower end opens toward the cover plate 12a, and the other end projects to the upper part of the cover plate 15, Cooling water recovery pipe
21 is fixed to the lid plate 15.

In the figure, reference numeral 22 is a welding groove provided in the welding portion 25 at the tip of the branch pipe 5, 23 is a root portion of the welding groove 22, and 24 is cooling water.

Next, the operation of the present invention will be described.

When welding the branch pipe 5 to the main pipe 6, a through hole 7 having substantially the same diameter as the inner diameter of the branch pipe 5 to be connected is previously drilled in the radial direction of the main pipe 6, and the through hole 7 is drilled. The end portion of the branch pipe 5 having the welding groove 22 formed in advance is positioned and set on the outside of the main pipe 6 at a certain position, and only one layer is welded to the root portion 23 of the welding groove 22 so as not to leak water. deep.

Next, the worker holds the pipe welding part cooling device in his / her hand, and holds the receiving plate 2 and the seal rubber plates 4a, 4b from the opening side of the branch pipe 5
The lid plate 15 is inserted therein until it comes into contact with the upper surface of the branch pipe 5.
As a result, the sealing device 4 is positioned inside the through hole 7 of the main pipe 6, and the sealing device 14 is positioned near the upper end of the inner circumference of the branch pipe 5.

When the cover plate 15 comes into contact with the upper surface of the branch pipe 5 and is positioned, for example, the cover plate 15 is temporarily attached to the upper surface of the branch pipe 5, and the wing nut 20 is projected in the direction in which the cooling water supply pipe 1 projects upward in FIG. Rotate to. Then, the receiving plate 2, the seal rubber plates 4b and 4a, the holding plate 9, the spacer 11, the receiving plate 13, and the seal rubber plates 14b and 14a also try to move upward by the amount of rise of the cooling water supply pipe 1,
Since the lid plate 15 cannot move upward, the seal rubber plates 4b, 4
a, 14b, 14a are provided between the receiving plate 2 and the pressing plate 9 and between the receiving plate 13 and the cover plate corresponding to the amount of rise of the cooling water supply pipe 1, that is, the receiving plate 2.
It is compressed vertically at 15 and expands radially. For this reason, the outer circumference of the seal rubber plates 4a, 4b, 14a, 14b is the through hole 7 of the main pipe 6.
The inner circumference and the inner circumference of the branch pipe 5 are brought into close contact with each other so that the space inside the branch pipe 5 can be sealed.

When the seal rubber plates 4a, 4b, 14a, 14b are in close contact with the inner circumference of the through hole 7 and the inner circumference of the branch pipe 5 of the main pipe 6, the cooling water supply pipe 1 is connected to the cooling water supply source and the cooling water recovery pipe 21 is cooled. Connect to the water circulation system.

When the cooling water 24 is supplied to the cooling water supply pipe 1 from a water supply source (not shown), the cooling water 24 passes from the small hole 3 below the cooling water supply pipe 1 through the small hole 10 below the spacer 11 to the sleeve body.
It flows out into the inner space of 12b, further flows into the through hole 7 of the main pipe 6 through the gap H between the lower end of the sleeve body 12b and the upper surface of the pressing plate 9, and the gap between the outer circumference of the sleeve body 12b and the inner circumference of the branch pipe 5. S
Through the inner space of the branch pipe 5 to the circulation system via the cooling water recovery pipe 21 and returned to a supply source (not shown). Meanwhile, when the cooling water 24 passes through the gap S at a specified flow velocity (0.05 M / S or more), the welding groove 22
The part is cooled from its inner surface.

As described above, the sealing devices 4 and 14 are arranged at the upper and lower ends of the branch pipe 5 to form the inner space of the branch pipe 5, and the cooling water supply pipe 1 serving as a water supply / drainage path to the inner space of the branch pipe 5 and cooling. Since the water recovery pipe 21 is provided, the cooling water 24 can be circulated and used, the sleeve body 12b having a predetermined diameter is provided in the branch pipe 5 at the welding groove 22 portion, and the outer peripheral surface of the sleeve body 12b and the inside of the branch pipe 5 are provided. By making the gap S with the peripheral surface a predetermined gap, the cooling water 24 passing through the gap S
The speed of can be kept above the specified value (0.05M / S).

In addition, in the embodiment of the present invention, the case where the branch pipe orthogonal to the main pipe is welded has been described, but it is possible to carry out even when the branch pipe is obliquely attached to the main pipe. Although the case of welding toward the upper side of the pipe has been described, the case of welding toward the lower side or the lateral direction of the main pipe can also be performed.The sleeve is not fixed to the spacer but is directly fixed to the cooling water supply pipe. Needless to say, various modifications can be made without departing from the scope of the present invention.

[Advantages of the Invention] As described above, according to the pipe welding portion cooling device of the present invention, various excellent effects as described below can be obtained.

(I) Since the seal device is provided to prevent the cooling water supplied into the branch pipe from flowing out to the main pipe, the cooling water can be recovered, and thus the cooling water can be circulated and used.

(II) A sleeve that can form a predetermined gap with the inner peripheral surface of the branch pipe is provided in the branch pipe of the welded portion, the outer diameter of the sleeve is appropriately selected, and the gap is defined to pass through the gap. The flow rate of the cooling water used can be higher than the specified flow rate of the water cooling welding (HSW) method.

(III) Since the residual stress at the time of welding can be suppressed by the above item (II), stress corrosion cracking can be prevented in advance.

(IV) Since all of the cooling water passes through the inner peripheral surface of the welded part, the welded part can be cooled efficiently.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the pipe weld cooling device of the present invention. In the figure, 1 is a cooling water supply pipe, 4 is a first sealing device, 5 is a branch pipe, 6 is a main pipe, 7 is a through hole, 12 is a sleeve, 14 is a second sealing device, and 21 is a cooling water recovery pipe. , 24 indicates cooling water, 25 indicates a welded portion, and S indicates a gap.

Claims (1)

[Scope of utility model registration request] 1. A pipe weld cooling device for cooling a main pipe and a welded portion of a branch pipe to be welded to an outer peripheral portion of the main pipe with cooling water, wherein A cooling water supply pipe that can be inserted into a branch pipe that communicates with a through hole that is bored toward the inner peripheral side, and that is externally fitted to the cooling water supply pipe and can be fitted into the through hole of the main pipe, A first seal device for preventing cooling water from leaking from the side of the branch pipe to the side of the main pipe; and a first seal device externally fitted to the cooling water supply pipe and fittable inside the branch pipe,
A second sealing device that prevents the cooling water from leaking to the outside from the branch pipe, and a second sealing device that is installed substantially concentrically to the cooling water supply pipe on the branch pipe side of the first sealing device. A sleeve for forming predetermined gaps for flowing cooling water between the sealing device and the inner peripheral surface of the welded portion, and a cooling water collecting pipe for collecting the cooling water passing through the gap, The sleeve is arranged so as to surround a small hole for circulating cooling water provided in the cooling water supply pipe, and the end portion of the sleeve on the first sealing device side is located closer to the first sealing device side than the welded portion. The pipe weld cooling device is characterized in that a lid plate is attached to an end of the sleeve opposite to the first sealing device so that cooling water does not flow.