WO2017070987A1

WO2017070987A1 - Construction method for gas pipeline system

Info

Publication number: WO2017070987A1
Application number: PCT/CN2015/094221
Authority: WO
Inventors: 高新伟
Original assignee: 浙江铭仕集团有限公司; 浙江铭仕兴新暖通科技有限公司
Priority date: 2015-10-29
Filing date: 2015-11-10
Publication date: 2017-05-04
Also published as: CN105221835A

Abstract

Disclosed is a construction method for a gas pipeline system. The method comprises the steps of: (1) determining materials for the gas pipeline system; (2) manufacturing the pipeline system according to a blueprint and the maximum integration principle; (3) carrying out blanking on the materials determined for use in the gas pipeline system and machining and manufacturing the pipelines and pipe fittings under factory conditions, wherein machined finished products are prefabricated pipes and prefabricated pipe fittings meeting the requirements of the blueprint; (4) carrying out construction preparation; (5) selecting installation; (6) positioning vertical pipes and assembling the prefabricated pipelines according to the design requirements and carrying out positioning using a pipe clamp; pre-tightening prefabricated adaptor unions using a spanner and a pipe wrench, wherein the direction can be freely adjusted; and (7) adopting a top to bottom installation sequence or starting installation from any floor. According to the present invention, the number of pipe joints is greatly reduced, pipeline integrity is improved, and the risk of leakage is reduced.

Description

Gas pipeline system construction method

Technical field

The invention relates to a construction method of a gas pipeline system, in particular to a construction method of a town gas pipeline.

Background technique

Gas pipeline systems have long used carbon steel pipes, of which galvanized steel pipes have been widely used. The construction method that has been used in gas pipeline systems is on-site measurement, on-site processing of pipeline threads, welding or threading, and anti-corrosion or painting operations after completion. The fittings and joints used are standard parts and are modified at the site according to specific requirements. The main problem is that the quality of the pipe welding on the construction site cannot be effectively monitored, the quality of the weld can not be guaranteed, especially in the installation of high-rise buildings, the number of pipe interfaces is large, the potential leak points are also many, and the pipes and equipment are heavy. Inconvenient installation; high technical requirements for construction personnel, difficult to install quality control; pipelines are easy to damage anti-corrosion layer or galvanized layer during transportation and construction; poor corrosion resistance of pipelines, short service life, capital and manpower for post-maintenance investment The cost is high and the safety and reliability of the gas pipeline system cannot be guaranteed.

The construction method of the traditional gas pipeline system is shown in Figure 1a and Figure 1b.

Figure 1a is a schematic diagram of the installation of the indoor pipeline. The specific implementation process is as follows: 1. The floor slab is punched according to the position determined by the design drawing (there are reserved holes omitted); 2. The measuring scale is based on the floor elevation, and the cutting/pipe cutting is performed; For the cut pipe, the ferrule machine is used to process the ferrule; 4, the pipe finished with the ferrule is wound with the PTFE raw material tape (sealing material); 5. The pipe tongs are used to tighten the galvanized threaded pipe fittings such as the tee or the elbow.

Specifically, after the riser determines the position, the live joint 11 is cut with galvanized on site. The pipe 1' is connected, and then connected to the inlet of the front valve 4 through the galvanized tee 5', the outer wire 7', and the outlet of the front valve 4 is connected to one end of the galvanized elbow 2', and the other of the galvanized elbow One end is connected to one end of the watch joint 6 through the outer wire, and the other end of the watch joint is connected to the inlet of the gas meter 8. The outlet of the gas meter 8 is connected to another galvanized elbow through the outer wire, and the galvanized elbow is in turn A cut galvanized pipe, a galvanized elbow, a ball valve 10, a cooker tube 12, and a gas stove 9 are connected. Among them, each section of the galvanized pipe is provided with a pipe clamp for fixing the pipe.

The disadvantages of the above construction method are that the installation is time consuming and the machine equipment and the pipeline are heavy; due to the large number of interfaces, the interface may be leaked and the airtightness test may not be passed. In addition, the indoor welding operation is also very cumbersome, the construction machine is moving back and forth, the on-site measuring ruler, the blanking, the threading thread or the welding, and the labor is repeated and the efficiency is low.

Figure 1b shows the installation of the outdoor pipeline. There are two methods for installing the outdoor pipeline: one is welding and the other is a threaded thread connection. If the welding method is adopted, the high-rise building will inevitably require the welder to work at heights. First, there is a large safety risk. Second, the welder has high skill requirements. Once the weld is unqualified, it is very difficult to repair the weld. In addition, the manual welding process is no matter There is no high reliability of automated welding technology.

The outdoor riser adopts the traditional ferrule thread connection. The method is basically similar to the installation of the indoor pipe. In the construction of the exterior wall of the building, there are also problems of inconvenient operation and heavy piping, increasing the risk of working at height and the inconvenience caused by operation. Quality defects, once the weld is unqualified, it is troublesome. Secondly, the outer wall pipe of the high-rise building is connected by a threaded thread. It is difficult to handle the air leakage after installation, and it is very difficult to maintain and replace it in the future.

The materials of the gas pipeline system also try to use stainless steel or other composite materials. Basically, only the material of the pipeline is different, and the connection method and construction process of the pipeline are not rooted. The improvement of the nature, especially the press-fit mechanical interface, has high construction operation requirements, heavy construction tools, poor interface strength and sealing performance, and is a one-time interface, which is very difficult to install and maintain.

Summary of the invention

In order to overcome the above-mentioned defects in the construction method of the gas pipeline system in the prior art, the present invention provides a method for greatly reducing the number of interfaces of the gas pipeline system, reducing construction difficulty, having good corrosion resistance, long service life, and safety risk. Low gas pipeline system construction method.

The technical solution adopted by the invention is:

A method of constructing a gas pipeline system, characterized in that the method comprises the following steps:

(1) Determine the materials for the gas pipeline system according to the three conditions of use conditions, corrosion resistance and welding performance;

(2) Gas pipeline system design pipeline, according to the principle of maximum integration, the specific design and layout of the pipe fittings, and according to the design drawings, according to the principle of maximum integration;

(3) According to the manufacturing drawings provided by the gas pipeline system, the materials for the gas pipeline system determined under the factory conditions shall be cut off, processed to manufacture the pipelines and pipe fittings, and the finished products shall be prefabricated pipes and prefabricated pipe fittings that meet the requirements of the design drawings. ;

(4) The welding of prefabricated pipes and prefabricated pipe fittings adopts automatic welding technology, and the inner and outer protective welding of argon gas with a purity of not less than 99.99% is adopted;

(5) 100% non-destructive testing of welded pipe welds;

(6) Applying atmosphere protection heat treatment or pickling passivation treatment to prefabricated tubes and prefabricated pipe fittings;

(7) Prefabrication of curved pipe by automatic three-dimensional numerical control bending equipment;

(8) Construction preparation: familiar with the drawings, understand the technical requirements of the pipeline system; check the factory certificate, warranty book and appearance of pipelines, gas meters and valves without defects and corrosion;

(9) Select the installation tool: electric hammer, wrench, pipe wrench;

(10) Position the riser according to the design requirements, assemble the prefabricated pipe, and position it with the pipe clamp; pre-tighten the prefabricated joint with wrench and pipe wrench, the direction can be adjusted freely; the pipe is assembled to the ground floor or reserved pipe The ground position can be converted by threaded joint or flange; the prefabricated pipe is sealed with a flexible sealing material through the floor and the wall;

(11) The installation sequence uses the installation process from top to bottom or from any floor, and the airtightness test of the piping system is carried out according to the design requirements.

The material used for gas pipeline system has tensile strength ≥ 485MPa, yield strength ≥ 205MPa, welding performance C (carbon content 0 ≤ 0.03, corrosion resistance PRE (pitting equivalent) ≥ 18, and is 100% recyclable, no environment Harmful environmentally friendly materials.

The invention changes the inconvenience and cumbersome process of the prior art for the gas pipeline on-site construction process, and the pipeline system design is completed in advance to minimize the joint and improve the integrity of the pipeline system; the pipeline system is in the factory according to the design drawings. It is processed and manufactured and shipped to the site for installation.

The principle of maximum integration referred to in the present invention means that the pipe joint is minimized and the degree of integration of the pipe is the highest, as long as the conditions of construction and installation permit.

The beneficial effects of the present invention are embodied in:

1. The pipe joint is greatly reduced, the integrity of the pipe is improved, the leakage risk is reduced, the pipe system is reduced by 70% interface, the number of potential leak points is reduced, the pipe joint strength is high, and the sealing performance is good.

2. Transfer the on-site processing and manufacturing of the pipeline system to a modern factory to realize intelligent and customized automated lean production, and the overall quality of the pipeline system is guaranteed.

3. Select sustainable development of environmentally friendly materials.

4. The reliability and safety of the piping system have been significantly improved.

5. Reduce construction difficulty and improve construction efficiency.

6, the construction is simple, no complicated tools and operational skills requirements, no need to use electricity.

7. Improve project quality and reduce construction costs.

8. There is no need for cutting, threading and welding operations at the construction site. No artificial anti-corrosion paint is required after completion; the quality caused by human factors is reduced, and there is no material loss and waste.

9. Significantly reduce the maintenance cost in the later period, and the intrinsic safety of the pipeline system has been significantly improved.

DRAWINGS

Fig. 1a is a schematic view showing the installation method of the prior art indoor pipe gas pipeline system.

Figure 1b is a schematic view showing the installation method of the prior art outdoor riser gas pipeline system.

Fig. 2a is a schematic view showing the installation method of the indoor gas pipe system of the present invention.

2b is a schematic view showing the installation method of the outdoor riser gas pipeline system of the present invention.

detailed description

Referring to Figures 2a and 2b, a construction method of a gas pipeline system is characterized by: The method described includes the following steps:

(6) 100% non-destructive testing of welded pipe welds;

(9) Select the installation tool: electric hammer, wrench, pipe wrench;

The material used for gas pipeline system has tensile strength ≥ 485 MPa, yield strength ≥ 205 MPa, welding performance C ≤ 0.03, corrosion resistance PRE ≥ 18, and is an environmentally friendly material that can be 100% recycled and harmless to the environment.

A specific embodiment of the construction method in the present embodiment will be described below, as shown in Figs. 2a and 2b.

2a is a schematic view showing the installation of the indoor pipe in the present embodiment. Specifically, after the riser determines the position, it is connected to the stainless steel prefabricated pipe 1 through the joint 11 and then connected to the inlet of the front valve 4 through the three-way screw 5, The outlet of the front valve 4 is connected to one end of the elbow joint 2, and the other end of the elbow joint 2 is connected to the inlet of the gas meter 8 through a meter joint, and the outlet of the gas meter 8 is passed through the table joint and the continuous curved thread table attachment. 7 connection, continuous bending thread table attachment 7 is sequentially connected with the ball valve 10, the cooker tube 12, the gas stove 9. Among them, the stainless steel prefabricated pipe 1, the elbow pipe joint 2 and the continuous elbow thread table attachment 7 are provided with a pipe clamp 3 for fixing the pipe.

The construction method in this embodiment is to transfer the on-site processing and manufacturing of the pipeline system to a modern factory to realize intelligent and customized automatic lean production, the quality of the pipeline system is guaranteed; and the pipeline system reduces the interface by 70% and reduces the potential leakage. The number of points, the strength of the pipe joint is high, and the sealing performance is good.

The outdoor pipe installation method of Figure 2b is basically similar to the installation of indoor pipes, as shown in Figure 2b.

The content described in the embodiments of the present specification is merely a column of implementation forms of the inventive concept. The scope of the present invention should not be construed as being limited to the specific forms of the embodiments. The scope of the present invention is also equivalent to the technical means that one skilled in the art can conceive according to the inventive concept.

Claims

A method of constructing a gas pipeline system, characterized in that the method comprises the following steps:

(1) Determine the materials for the gas pipeline system according to the three conditions of use conditions, corrosion resistance and welding performance;

(2) Gas pipeline system design pipeline, according to the principle of maximum integration, the specific design and layout of the pipe fittings, and according to the design drawings, according to the principle of maximum integration;

(3) According to the manufacturing drawings provided by the gas pipeline system, the materials for the gas pipeline system determined under the factory conditions shall be cut off, processed to manufacture the pipelines and pipe fittings, and the finished products shall be prefabricated pipes and prefabricated pipe fittings that meet the requirements of the design drawings. ;

(4) The welding of prefabricated pipes and prefabricated pipe fittings adopts automatic welding technology, and the inner and outer protective welding of argon gas with a purity of not less than 99.99% is adopted;

(5) 100% non-destructive testing of welded pipe welds;

(6) Applying atmosphere protection heat treatment or pickling passivation treatment to prefabricated tubes and prefabricated pipe fittings;

(7) Prefabrication of curved pipe by automatic three-dimensional numerical control bending equipment;

(8) Construction preparation: familiar with the drawings, understand the technical requirements of the pipeline system; check the factory certificate, warranty book and appearance of pipelines, gas meters and valves without defects and corrosion;

(9) Select the installation tool: electric hammer, wrench, pipe wrench;

(10) Position the riser according to the design requirements, assemble the prefabricated pipe, and position it with the pipe clamp; pre-tighten the prefabricated joint with wrench and pipe wrench, the direction can be adjusted freely; the pipe is assembled to the ground floor or reserved pipe Ground position, threaded union or flanged Change; the prefabricated pipe passes through the floor and the wall is sealed with a flexible sealing material;

(11) The installation sequence uses the installation process from top to bottom or from any floor, and the airtightness test of the piping system is carried out according to the design requirements.
The method for constructing a gas pipeline system according to claim 1, characterized in that the tensile strength of the material for the gas pipeline system is ≥ 485 MPa, the yield strength is ≥ 205 MPa, the welding performance is C ≤ 0.03, and the corrosion resistance is PRE ≥ 18.