JP2002174393A - Gas block device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas block device allowing a safe welding repair by perfectly interrupting a gas fluid in the front of a repairing position within a pipe. SOLUTION: This gas block device 1 to be inserted to the pipe 3 for passing the gas fluid 25 to isolate a prescribed position 31 of the pipe 3 from the gas fluid 25 comprises a gas recovery pipe 17 for discharging the gas fluid 25; a sealing member interposed between the gas recovery pipe 17 and the pipe 3; a gas insert pipe 18 for introducing an inert gas to the sealed space of the sealing member; and a gas discharge pipe 19 for discharging the inert gas 24. The sealing member comprises a tip ring 13, O-rings 15 and 16, an intermediate ring 24 and a fastening pipe 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for a gas block, and more particularly to a gas block which shuts off a gas fluid when performing welding repair or the like in a flammable gas pipe and enables safe repair. For equipment.

[0002]

2. Description of the Related Art In welding and repairing flammable gas pipes, if it is difficult to purge a repaired portion due to a valve installation position, valve leakage, or the like, a gas bag is conventionally inserted into the pipe and the gas bag is unplugged. 2. Description of the Related Art A gas fluid is shut off by inflating with an active gas and brought into close contact with an inner wall of a pipe to repair an unhealthy pipe.

The prior art will be described with reference to FIG. In the conventional gas bag 4 ', the gas fluid 25' is sealed by inserting the gas 27 'into the pipe 3' having the repair part 31 'and then sealing the gas 27' therein. Therefore, all the pressure of the gas fluid 25 'is received by the gas bag 4', and there is a risk of moving or bursting. Further, since it is a single block and it is difficult to complete the seal, it is particularly difficult. If the gas is flammable, there are problems such as danger.

[0004]

SUMMARY OF THE INVENTION The present invention is to solve the problems of the prior art, and it is possible to completely shut off the gas fluid at the front of the repair work site inside the pipe and perform safe welding repair. It is an object to provide an apparatus for a gas block.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a gas block device which is inserted into a pipe through which a gas fluid flows to isolate a predetermined portion of the pipe from the gas fluid. A recovery pipe, a sealing member interposed in a gap between the gas recovery pipe and the pipe, a gas insertion pipe for introducing a replacement gas into a sealed space of the sealing member, and a gas discharge pipe for discharging the replacement gas. And a gas block device having:

Further, the above-mentioned sealing member of the present invention is a gas block device comprising a tip ring, an O-ring, an intermediate ring and a tightening pipe.

The intermediate ring according to the present invention is a gas block device having an insertion purge hole and a discharge purge hole.

Further, the present invention is the apparatus for a gas block, wherein the gas fluid is a flammable gas, and the replacement gas is an inert gas.

[0009]

Embodiments of the present invention will be described. An embodiment of the gas block device of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory diagram of a gas block device according to an embodiment. FIG. 2 is an explanatory diagram of a method of using the gas block device of the embodiment.

An embodiment will be described. As shown in FIG. 1, the gas block device 1 of this embodiment includes a holding nut 11,
Tightening pipe 12, tip ring 13, intermediate ring 14, one-stage O-ring 15, two-stage O-ring 16, gas recovery pipe 17, N
It is composed of two insertion tubes 18 and an N2 discharge tube 19.

The holding nut 11 is provided with a tip ring 13, 1.
Step O-ring 15, intermediate ring 14, and two-step O-ring 16
Is pressed so as not to come off from the gas recovery pipe 17. The fastening pipe 12 is fastened to the gas recovery pipe 17 and has a one-stage O
The ring 15 and the two-stage O-ring 16 are tightened and their movement is suppressed. The tip ring 13 receives the pressing of the holding nut 11 and holds the first-stage O-ring 15. The intermediate ring 14 is provided with an insertion purge hole 141 and a discharge purge hole 142, and N2 (nitrogen) entering the sealed space from the N2 insertion pipe 18 through the insertion purge hole 142.
The gas is discharged to the outside through the discharge purge hole 141 and the N2 discharge pipe 19. The first-stage O-ring 15 and the second-stage O-ring 16 are tightened by the tightening pipe 12 to secure the hermeticity between the gas block device 1 and the pipe 3. The gas recovery pipe 17 recovers the gas fluid and relieves the static pressure acting on the gas block device 1. The N2 insertion tube 18
Insert N2 gas. The N2 discharge pipe 19 discharges N2 gas.

A method of using the gas block device 1 according to the present embodiment will be described with reference to FIG. The gas block device 1 is connected to the pipe 3 through which the gas fluid 25 flows.
Insert The pipe 3 is inserted up to a repair location (a predetermined location isolated from the gas fluid) 31. The press nut 11 of the gas block device 1 is
, But the clamping tube 12 is a single-stage O
Since the ring 15 and the two-stage O-ring 16 are attached so that no surface pressure is applied, they can be easily inserted into the pipe 3. The tightening pipe 12 is screwed inside the pipe 3,
The first O-ring 15 and the second O-ring 16 are tightened by applying a surface pressure. The first-stage and second-stage O-rings 15 and 16 are in close contact with the inner wall of the pipe 3 to block the gap. The gas fluid 25 is discharged out of the system by the gas recovery pipe 17. Then, the cooling device 21 is mounted outside the pipe 3. A replacement gas, for example, an N 2 (nitrogen) gas 23 is introduced from the N 2 insertion pipe 18. The replacement gas 23 enters a sealed space surrounded by the first-stage O-ring 15, the second-stage O-ring 16, the pipe 3, and the gas recovery pipe 17 from the insertion purge hole 141 of the intermediate ring 14. Since the pressure of the replacement gas 23 is applied to the sealed space, the possibility that the fluid gas 25 enters the sealed space from the gap between the pipe 3 and the first-stage O-ring 15 is low, and the sealed space enters the sealed space from the gap. Since the fluid gas 25 is also discharged together with the replacement gas 24 that is discharged, the fluid gas 25 such as the flammable gas does not approach the welding repair location. Since the outside of the pipe 3 is cooled by the cooling water 22 from the cooling device 21, the first and second stages of the gas block device 1 are
The rings 15, 16 are hardly affected by the heat from the welding operation at the repair location 31. After the repair work is completed, the insertion of the N2 gas 23 is stopped, and the tightening pipe 12 is loosened. The apparatus 1 is pulled out from the pipe 3, the cooling device 21 is removed, and the process is completed.

As described above, the gas block device of the present invention has the following features. 1. The structure is such that the gas fluid flowing inside the piping is safely discharged out of the system, and the pressure applied to the gas block device is minimized. 2. It is equipped with two stages of O-rings, and can be double-blocked and purged, so that the gas at the repair location is completely shut off. 3. This structure has a cooling device to prevent the effect of welding heat on the O-ring and the effect of welding heat on the front (upstream of gas fluid) structure. It can be applied to a small-diameter pipe of about 4.3 / 4B, and can have a compact and lightweight structure that can be carried around. 5. By using a rubber having a high deformability and a high heat resistance for the O-ring, it is possible to obtain a structure that enhances the sealing property. 6. This structure protects the O-ring even when the O-ring has no heat resistance. 7. Even when the gas flow from the front surface is large and the device is subjected to pressure, it is a structure that can ensure the sealing performance up to about 0.1 MPa.

According to the present invention, there are the following improvements. 1. Since double block and purge are possible only with this device, safe repair can be performed even with piping without a main valve or piping with leaking valves. 2. The present apparatus has a double block structure, easily maintains the purge performance, and is easy to operate. 3. By providing a collection line and reducing the cross-sectional area, the pressure applied to the apparatus is kept to a minimum, thereby improving the O-ring adhesion and preventing the apparatus from slipping out. 4. An O-ring is arranged in two stages, an inert gas is inserted between the O-rings, and a diffusion line is provided. Even if the first-stage O-ring leaks, the leaked gas can be discharged out of the system, and repair work can be performed safely. 5. Compact, lightweight and easy to transport, so it can be used anywhere. 6. By providing a cooling device, the O-ring is protected against thermal effects such as welding. 7. It can be applied to various pipes and has high versatility. 8. By changing the material of the O-ring, other gas bodies,
Can also be used for liquids. 9. Reuse of the O-ring is possible. 10. By using this apparatus, repairs that require block purging of the entire line can be repaired in a short time and at low cost. 11. It has a structure that recovers gas fluids without releasing them to the atmosphere, and is an environment-friendly device.

Although the gas block device of the present invention has been described with respect to a gas fluid in the embodiment, the present invention can be applied to other fluids such as liquids.

[0016]

According to the present invention, it is possible to obtain a gas block device capable of completely shutting off a gas fluid at the front of a repair work site inside a pipe and performing safe welding repair.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a gas block device according to an embodiment.

FIG. 2 is an explanatory diagram of a method of using the gas block device of the embodiment.

FIG. 3 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas block apparatus 11 Holding nut 12 Tightening pipe 13 Tip ring 14 Intermediate ring 141 Insertion purge hole 142 Discharge purge hole 15 1st-stage O-ring 16 2nd-stage O-ring 17 Gas recovery pipe 18 N2 insertion pipe 19 N2 discharge pipe 21 Cooling device 22 Cooling water 23 Inserted N2 gas 24 Discharged N2 gas 25 Gas fluid 26 Exhaust gas fluid 3 Piping 31 Repair location

Claims (4)

[Claims] Claims: 1. Inserting inside a pipe through which a gas fluid flows,
What is claimed is: 1. A gas block device for isolating a predetermined portion of a pipe from a gas fluid, comprising: a gas recovery pipe for discharging the gas fluid; a sealing member interposed in a gap between the gas recovery pipe and the pipe; An apparatus for a gas block, comprising: a gas insertion pipe for introducing a replacement gas into a sealed space of a member; and a gas discharge pipe for discharging the replacement gas. 2. The gas block device according to claim 1, wherein the sealing member comprises a tip ring, an O-ring, an intermediate ring, and a tightening pipe. 3. The gas block device according to claim 2, wherein the intermediate ring has an insertion purge hole and a discharge purge hole. 4. The gas block device according to claim 1, wherein the gas fluid is a flammable gas, and the replacement gas is an inert gas. Equipment for blocks.