CN110242821B

CN110242821B - Reinforcing method for gas pipeline plugging construction

Info

Publication number: CN110242821B
Application number: CN201910496690.7A
Authority: CN
Inventors: 宋卓林; 傅明华; 金俣垚
Original assignee: Shanghai Energy Construction Group Co ltd
Current assignee: Shanghai Energy Construction Group Co ltd
Priority date: 2019-06-10
Filing date: 2019-06-10
Publication date: 2021-02-19
Anticipated expiration: 2039-06-10
Also published as: CN110242821A

Abstract

The invention provides a gas pipeline plugging node reinforcing method, which mainly comprises the following steps: step 1) detecting stress before the pipe breakage of a main pipe of a gas pipeline, and confirming a plugging node; step 2) selecting a proper split four-way part according to the stress detection value and the diameter confirmation of the main pipe pipeline; step 3) connecting the split four-way part to the air inlet end and the air outlet end of the main pipe pipeline to be repaired; step 4), welding and fixing the split four-way part; step 5), detecting the stress of the welded mother pipe; and 6) carrying out rust prevention treatment on the generated welding line to finish the reinforcement of the plugging node. Compared with the conventional method, the method has the characteristics of greatly increasing the rigidity and the deformation resistance of the plugging node, high plugging efficiency, wide application range, low cost and the like.

Description

Reinforcing method for gas pipeline plugging construction

Technical Field

The invention relates to the field of gas pipeline construction, in particular to a reinforcing method for gas pipeline plugging construction.

Background

In the use process of the gas pipeline, the damage of the pipe network caused by natural environment, objective factors, human factors and the like occurs sometimes, and the gas pipeline needs to be repaired, replaced or replaced with pipeline accessories. And with the development of the gas industry, gas users increase, and newly-increased pipelines also increase continuously. On the other hand, the pipeline is frequently rerouted under the influence of engineering construction. The plugging operation of the pipeline can not be left no matter the pipeline is repaired or the pipeline is reconstructed. The pipeline plugging is divided into transportation-stopping plugging and transportation-stopping plugging. For the stop of the transportation and the plugging, the local pipe network where the target pipe section is located is required to stop the transportation of gas, the inert gas is used for replacing the gas in the pipeline, and the construction of the pipeline is carried out after the residual gas in the pipeline is led out and discharged for burning. Although the process is safe to operate, the gas stop of local pipe networks and the downstream of pipelines can be caused, the number of affected users is wide, and the economic loss is large. And a large amount of fuel gas is discharged and burned, so that a large amount of resource waste and environmental pollution are caused. The technique of non-stop conveying and pressure plugging completes operations such as opening, plugging, valve changing, line changing and the like of the pipeline by using a mechanical means, and is an effective special technique for maintaining and repairing the pipeline with pressure. The main characteristic is that the maintenance and the first-aid repair are completed under the condition that the pipeline is not in a conveying and pressure-bearing state by temporarily changing the flow channel of the medium in the pipeline. The influence range is limited to a small section of pipeline including an operation point, and the downstream fuel gas can be continuously supplied during construction through the bypass pipe, so that the economic loss is reduced. The continuous transportation plugging technology effectively overcomes the defects caused by the continuous transportation plugging, thereby becoming more and more choices for the construction of in-service gas pipeline engineering.

Although the blocking technology has a plurality of advantages without stopping transportation, corresponding problems are brought, after the technology is adopted for operation, the continuity of a pipeline at a blocking position is damaged, and a special blocking node is formed at an operation section. Whether the node can meet the requirement of pipeline service or not is not supported by effective scientific data. The main three plugging processes of the current large-caliber gas pipeline are as follows: among three processes of a bag type, a disc type and a cylinder type, the cylinder type plugging is a process for plugging a target pipeline by using an expansion cylinder, has the characteristics of high plugging efficiency, wide application range and low cost, is slightly influenced by out-of-roundness of the pipeline in the construction process, is not influenced by long-term accumulated scale and impurities in the pipeline, has the characteristics of simple construction process, good plugging effect and lower engineering cost, and is widely applied in the national gas industry. However, in the barrel-type plugging process, the target pipeline needs to be disconnected during the construction process, and the continuity of the main pipe is completely destroyed, so that structural welding and plugging point reinforcement need to be performed at the two disconnected main pipes. The currently used plugging processes all have the following defects:

1. the blocked section caused by blocking is longer, and is generally more than 2 times of the inner diameter of the blocked pipeline.

2. The requirement on the deformation of the pipeline is small, and the pipeline with large deformation is not suitable for use.

3. The reinforcing effect of the plugging interface is not supported by scientific data, and the possibility of instability of the plugging effect is caused, so that the better popularization and application of the technology are hindered.

4. The traditional reinforcing method is to directly increase the wall thickness of the reinforcing four-way part. However, the method usually increases a lot of cost, not only has long processing time, but also greatly increases the self mass of the four-way part, and objectively increases the bearing of the mother pipe. For example, the wall thickness of the four-way part is increased from 6mm to 9mm, and the weight is increased by more than 50%.

Disclosure of Invention

The invention aims to solve the technical problems that the strength of a four-way part in a cylinder type plugging process is not enough and the four-way plugging part can achieve enough compression resistance and deformation resistance under the condition of not increasing the weight of the four-way plugging part according to the stress characteristics of plugging nodes under different working conditions, and provides a reinforcing method for gas pipeline plugging construction, which comprises the following steps:

step 1) detecting stress before the pipe breakage of a main pipe of a gas pipeline, and confirming a plugging node;

step 2) selecting a proper split four-way part according to the stress detection value and the diameter confirmation of the main pipe pipeline;

step 3) connecting the split four-way part to the air inlet end and the air outlet end of the main pipe pipeline to be repaired,

step 4), welding and fixing the split four-way part;

step 5), detecting the stress of the welded main pipe;

and 6) carrying out rust prevention treatment on the generated welding line to finish the reinforcement of the plugging node.

Further, C plates can be welded on the upper opening end and the lower sealing end of the four-way part in the step 5) for further enhancing the reinforcing effect.

Furthermore, the split four-way part is positioned in the middle of the plugging node.

Furthermore, the split four-way part is connected with the main pipe in the gas pipeline plugging process into a whole through welding.

Further, the bisected four-way element includes: an upper open end and a lower sealed end.

Further, the upper open end includes an upper skirt, a chimney, and a flange interface.

Further, the flange interface is used for connecting the bridging pipe.

Further, the lower sealed end comprises a lower guard plate, a vertical cylinder and a sealing bag.

Furthermore, the edges of the upper guard plate and the lower guard plate are parallel to the axis of the pipeline of the main pipe;

furthermore, the split four-way part is made of 20# steel.

Further, the main pipe is made of Q235B steel.

Further, the two C-plates are arranged in parallel.

Furthermore, the C plate is a C-shaped plate and is welded and fixed with the upper guard plate area, the lower guard plate area and the vertical cylinder of the upper opening end and the lower sealing end of the split four-way part through three surfaces respectively.

Furthermore, the guard plate contact surfaces of the C plate and the upper guard plate area and the lower guard plate area are inclined surfaces capable of being attached to the upper guard plate and the lower guard plate.

Furthermore, the vertical cylinder contact surface of the C plate and the vertical cylinder is a vertical surface attached to the vertical cylinder.

Further, the C plate is made of Q235 steel.

The invention has the following beneficial effects:

1. the rigidity and the deformation resistance of the plugging node can be greatly improved.

2. The cylinder type plugging device has the advantages of high efficiency, wide application range and low cost.

Drawings

FIG. 1 is a schematic view of a split four-way component of the present invention in combination with a parent tube;

FIG. 2 is a schematic view of the split four-way component of the present invention welded to a C plate;

FIG. 3 is a schematic view of a C plate of the present invention;

in the figure: the flange interface 1, go up backplate 2, chimney 3, lower backplate 4, sealed bag 5, female pipe 6, C board 7, backplate contact surface 8, chimney contact surface 9.

Detailed Description

The invention is described in further detail below with reference to the data in conjunction with the figures. It should be understood that the embodiments are merely illustrative of the present invention and do not limit the scope of the invention in any way.

Example 1

A gas pipeline plugging node reinforcing method comprises the following steps:

step 1), detecting stress before pipe breakage of a gas pipeline main pipe 6;

step 2) selecting a proper split four-way part according to the stress detection value and the diameter confirmation of the pipeline of the main pipe 6;

step 3) connecting the split four-way part to the air inlet end and the air outlet end of the pipeline of the main pipe 6 to be repaired,

step 4), welding and fixing the split four-way part;

step 5) detecting the stress of the main pipe and the split four-way part after welding;

In the step 5), C plates 7 may be welded to the upper opening end and the lower sealing end of the four-way component to further enhance the reinforcing effect, as shown in fig. 2.

As shown in fig. 1, run from opposite directions the four-way part and be located the middle part of shutoff node, run from opposite directions the four-way part and be connected as an organic whole through the female pipe 6 of welding and gas pipeline shutoff in-process, run from opposite directions the four-way part and include: upper portion open end and lower part are sealed to be held, and the upper portion open end includes upper shield 2, chimney 3 and flange interface 1, and flange interface 1 is used for connecting the bridging pipeline, and the sealed end of lower part includes backplate 4, chimney 3 and sealed bag 5 down, and

upper shield

2 and 4 edges of backplate down are on a parallel with female pipe pipeline axle center, and run from opposite directions the cross part and be 20# steel, and female pipe is Q235B steel.

As shown in fig. 3, the C plate 7 is made of Q235 steel, the two C plates 7 are arranged in parallel, the C plate 7 is a C-shaped plate, and is welded and fixed with the upper guard plate 2 region, the lower guard plate 4 region and the vertical cylinder 3 of the upper opening end and the lower sealing end of the split four-way component through three surfaces, the guard plate contact surface 8 of the C plate 7 with the upper guard plate 2 region and the lower guard plate 4 region is an inclined surface capable of being attached to the upper guard plate and the lower guard plate, and the vertical cylinder contact surface 9 of the C plate 7 with the vertical cylinder is a vertical surface attached to the vertical cylinder.

Example 2

After the step 2) selects proper split four-way parts according to the stress detection value and the diameter confirmation of the pipeline of the main pipe 6, the C plate can be welded on the upper opening end and the lower sealing end in advance, and the subsequent welding processes are reduced.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims

1. A reinforcing method for gas pipeline plugging construction is characterized by comprising the following steps:

step 4), welding and fixing the split four-way part;

step 5), detecting the stress of the welded mother pipe;

step 6) carrying out rust prevention treatment on the generated welding line to finish the reinforcement of the plugging node,

the split four-way part is positioned in the middle of the plugging node and comprises an upper opening end and a lower sealing end;

the upper opening end comprises an upper guard plate, a vertical cylinder and a flange interface;

the lower sealing end comprises a lower protection plate, a vertical cylinder and a sealing bag;

welding C plates on the upper opening end and the lower sealing end in the step 4) for strengthening the reinforcing effect;

the contact surface area of the plate C and the upper guard plate, the contact surface area of the lower guard plate and the contact surface of the vertical cylinder are fixed through welding;

the contact surface of the C plate with the upper guard plate and the lower guard plate is an inclined surface which can be attached to the upper guard plate and the lower guard plate;

and the vertical cylinder contact surface of the C plate and the vertical cylinder is a vertical surface attached to the vertical cylinder.

2. The reinforcement method according to claim 1, wherein the edges of the upper and lower guard plates welded in step 4) are parallel to the axis of the main pipe.

3. The reinforcement method of claim 1, wherein the split cross-piece is 20# steel.

4. The reinforcement method of claim 1, wherein the parent pipe is Q235B steel.