Copper pipes for gas: specifics and norms for laying a copper pipeline
For the installation of gas pipelines using pipes from various materials: HDPE, steel and copper. Polymeric products are used only for underground laying, steel wiring is mounted inside houses and apartments.
Today, when the quality of metal has improved and the opportunity has appeared to produce products of the required thickness and length, copper pipes for gas have increasingly been installed. They are excellent for low pressure gas pipelines and have suitable characteristics for strength, flexibility and wear resistance.
If you decide to assemble an intra-house gas pipeline yourself, it will not be superfluous to get acquainted with the properties of copper pipes and press fittings, learn more about the assembly methods and the requirements that apply to products.
The content of the article:
What are the requirements for copper pipes
Companies manufacturing products for the installation of gas pipelines never use copper alloys with other materials in production, as quality is lost. The purity of the metal should not be below 99.9%.
Grades used for the manufacture of pipes:
- at domestic enterprises - M1, M2, M1r, M2r;
- foreign analogues - Cu-DHP.
Depending on the production method and physical properties, finished products are divided into 3 categories: soft (R - tensile strength 220 MPa), semi-solid (R - tensile strength 250 MPa), solid (R - tensile strength 290 MPa).
It is noted that long-term storage affects the quality of copper - it becomes harder. It is possible to return former qualities by means of annealing. In order not to make additional recovery measures, we do not recommend buying installation products with a margin.
According to the manufacturing technology, gas pipes are divided into 2 groups:
- welded - in the production of which welding is used, therefore, there are seams;
- seamless - monolithic, seamless products.
The second group is preferable to use, since the seams will always be areas from the risk zone, that is, have reduced characteristics in terms of tightness.
In addition to the usual copper pipes and fittings Products with an outer shell are also made from polymeric materials - PVC or foamed polyethylene. The advantages of such products are additional external protection and a kind of disguise.
Sewing a gas pipeline from copper into a concrete wall or hiding it behind drywall is prohibited by law.
Norms and regulation of standards
The gas pipeline refers to structures that pose a potential danger to the residents of the house, therefore both the production of products and installation work are subject to the requirements set forth in the regulatory documentation.
The basis for modern codes of practice were the norms of 1987 - SNiP 2.04.08-87.
Now you can find interesting information on copper pipelines in the following documents:
- SP 42-101-2003 - on the design and construction of gas distribution systems;
- SNiP 42-01-2002 - norms and rules of GDS;
- OST 153-39.3-051-2003 - operation of GDS.
Together with the main documents, it is necessary to study additions and refinements that appear periodically in connection with the development of technologies and the release of new products. Suppose SNiP 42-01-2002 in 2011 was amended and supplemented with materials, including requirements for copper products. New revision - SP 62.13330.2011.
The general requirements should be added and the rules of installation of structures from copper gas pipes. A sample of such a document is the STO “Design, installation and operation of gas pipelines from copper pipes for gasification of residential and public buildings”, where the details of the gas pipeline assembly and requirements for pipes are analyzed in detail.
For more information on the requirements for copper pipes and fittings, see the following documents:
- GOST 617-90;
- GOST 859-78;
- GOST R 52318-2005;
- EN1057 - European standards;
- GOST R 52948-2008;
- GOST R 52922-2008;
- GOST R 52949-2008.
We warn that when using products that do not meet legally sound requirements, the operation of the gas pipeline becomes dangerous.
Attracting fans to the installation work is not the best solution. We advise you to contact a company that has long been engaged in the installation of domestic gas pipelines and has experienced gas system installers.
The qualifications of employees are documented, so you have the right to request a certificate.
For soldering or welding, experts are allowed who, according to OK 016, have received 4th category and above. The conclusion is given by the certification committee based on the rules of RD 03-495-02 and PB 03-273-99.
Crimping can be done by workers with the 3rd category and higher, having experience in assembling copper gas pipelines and having passed certain tests. In order to gain admission to practice, the contractor must perform at least 3 high-quality and tested by the commission connections press fittings. Monitoring of the work performed is determined according to the rules of SNiP 3.01.01.
Features of the assembly of a copper gas pipeline
The assembly and connection of copper pipes for an intra-home gas pipeline differs from installation work carried out with other types of products - for example, polymer or steel.
Brazing alloy is used without flux, popular materials include PMFOtsr6-4-0-0.03 and PMFS6-0.15 - copper-phosphorus compounds.
If soldering is used as an advantage for intra-house wiring, then at the entrance to the house where large-diameter pipes are mounted, the connecting work is performed by argon-arc or gas welding.
Other rules for installation work on the installation of a copper gas pipeline:
Plastic brackets and other polymer fasteners are not allowed. If strobes are cut out for arranging the internal wiring, then they cannot be closed from the outside, and the space around the pipes in the strob should be free.
Pipe Installation Instructions
The gas pipeline installation includes 3 stages:
- pipe preparation;
At the end, a trial run is made and the pipeline is checked for leaks.
We will analyze the main ways of preparing parts for installation - bending and cutting, as well as two popular methods of connecting pipes - pressing and soldering.
How is copper cutting and bending
Before the beginning installation work need to prepare the pipes. Completely straight gas pipelines are rare, more often they consist of combinations of straight and bent elements. This means that the pipe material must be cut, and some parts must be carefully bent at a given angle, 90 ° or blunt.
For cutting, you can use a hacksaw for metal, a circular electric saw, but the pipe cutter is considered the most acceptable tool.
During the cutting process, make sure that the pipe does not deform - any bulges, cracks or dents will endanger the tightness of the gas pipeline.
Bending can be carried out cold and hot. The first is used for thin pipes, most often used in everyday life, with a diameter of up to 22 mm. The hot method is used for products with a large diameter. The pipe is heated by filling the bend with sand. This is necessary so that there are no creases.
For heating, experienced craftsmen use a torch, acetylene-oxygen or acetylene-air. Operating temperature - from + 650 ° C. The readiness of copper is determined by the shade: as soon as it becomes dark red, you can bend. The procedure is carried out quickly, but carefully.
Connection methods: crimping and soldering
If you have the time, proven skills and experience, you can try to solder the copper pipes yourself. This method is longer than crimping, but it is inexpensive and reliable.
- Preparation of parts: cutting and bending pipes, if necessary - flaring and calibration.
- Stripping the ends of the connected segments, eliminating any defects.
- Insert the end of one pipe into the expanded end of the other.
- Warming up the soldering section to the melting point of the solder.
- Solder feeding into the gap between the two parts.
- Cooling the soldering zone and stripping the joint to a shine.
After soldering, diagnostics are performed. Leak testing of the system is carried out by a special commission.
Connecting using press fittings is a reliable modern method, the main advantage of which is the fast assembly speed of the gas pipeline.
Instructions for connecting the elements of the pipeline by pressing:
If the hand is full, then when assembling a small fragment, first connect several elements to the fittings, and then they are pressed with one run. It is recommended to assemble the intra-house gas system in parts - first separately complex sections with a large number of bent elements, and then already between them.
In the connection of copper pipes, collet (crimp) fittings are also used, which are practically not used in the assembly of gas pipelines due to the not very high reliability of the collapsible assembly. The most reliable compounds are those formed by soldering.
However, for implementation soldering copper pipes experience and an appropriate tool are needed: a blowtorch for a low-temperature connection, a propane or acetylene torch for a high-temperature.
Conclusions and useful video on the topic
An example of installing a copper gas pipeline in a country house:
How to crimp copper fittings:
About the benefits of replacing pipes with copper:
A home gas pipeline made of copper pipes is reliable and aesthetically appealing. It is considered one of the best options for installation in a private house or apartment. But, planning to install a copper structure, do not forget about safety: if you do not have experience working with pipes, it is better to entrust the installation to specialists.
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