How to safely crash into a gas pipe in an apartment or house

It is necessary to replace gas pipes in a private house or apartment, in fact, like any other utilities, after many years of operation. Therefore, when planning to repair your home, do not lose sight of the life of the elements of the pipeline. Indeed, in old pipes, the appearance of leaks is not excluded. And their replacement will require, at least in part, re-work on the interior design of residential premises.

Insertion work into a gas pipe may only be carried out by a specialist in compliance with all safety requirements.

A bit of math and numbers

One of the main factors ensuring uninterrupted gas supply is the throughput of the gas pipeline. Therefore, the calculation of this parameter has special requirements. Such calculations need to be performed independently of type of gas pipesto be used - steel or plastic.

The maximum value of the pipe throughput is determined by the formula:

Qmax = 196.386T × (P / Z) × (DN / 2), where

P - absolute gas pressure or operating pressure in the gas pipeline system plus 0.1 MPa; Du - the value of the conditional passage of the pipe; T is the temperature of the transported gas in degrees Kelvin; Z is the compressibility factor. An analysis of this formula indicates that the higher T, the throughput should be higher, otherwise the gas pipeline will be depressurized, which can lead to an explosion.

Helpful information! There is a more complex formula. But this is quite enough to select a gas pipe by the parameter “throughput”.

From the correct choice of pipes depends not only the performance of the gas pipeline, but also the safety of the entire system

However, you can make a choice using the data from the table below. It presents the throughput of pipes depending on the pressure created by the gas.

Table 1

How to start replacing a gas pipe

A gas pipeline is a system that serves both for transportation and storage of gas. Designs of this type vary depending on the mission they perform. For example, networks designed to transport blue fuel over long distances are characterized by high pressure. In view of this, experimenting with such systems is dangerous, because it can provoke a disaster that affects neighbors, and not just you. Let the relevant organizations better worry about this. Indeed, knowledge of how to insert a high-pressure gas pipe is included in the circle of professional duties of their employees. Moreover, according to the normative documents in force on the territory of our country, it is prohibited for persons who do not have permission to carry out such work. Therefore, you should call the master and wait for his arrival.

Most likely, at the first visit, the gas service employee will not change the pipe for you. He will need to inspect the system, measure the length of its elements and, based on the data received, draw up an estimate for the work, including the price of new pipes needed to modify the domestic gas pipeline.

Work Rules

The replacement procedure begins with safety instructions. The master must take care of the absence of sources of open fire and remove smokers, as well as unauthorized persons from the site.

The method and technology of tapping into a gas pipe depends on the pressure in this gas pipeline

In addition, at the entrance to the place of work it is necessary to hang out a warning sign “Passage is forbidden!”, “Caution, gas!”, “Smoking is prohibited!” etc. These are generally accepted requirements. However, making a tie-in into a gas pipe requires compliance with certain rules for handling such systems. The main ones are formulated as follows:

• insertion into the low pressure network is allowed if the value of this parameter does not exceed 80 millimeters of water column, but not less than 20;
• connection to networks or high-pressure / medium-pressure pipelines is possible only when it is reduced to an acceptable level;
• perform cutting and welding gas is allowed in areas with pressure within 40≤P≤150. Compliance with this corridor must be monitored throughout this operation.

According to the law, without pressure reduction, only organizations authorized to carry out such activities are entitled to carry out work (sometimes it is even necessary to obtain a special outfit).

Important! The inability to reduce pressure is considered as a non-standard circumstance. In order to make an insert in this case, you will need special equipment.

Preliminary stage. Sidebar Types

Regardless of whether you plan to use the services of a specialized company or want to crash into the system yourself, start the work from the preparatory stage.

Before bumping into a gas pipeline, you need to make calculations and obtain permission from the gas service

In the first case, contact the appropriate authority. But be prepared for the fact that in addition to filling out an application, you may be required to provide a package of documents prescribed by law. If it is necessary to crash into the gas pipe of a newly erected house, the package may include:

• permission to connect to the gas pipeline issued by the architectural and planning institution;
• certified by the gas service snapshot of the topographic survey of the site. In addition to the gas pipeline, other utilities must be applied to it: water supply and heating pipes, as well as sewer pipes;
• technical passport for the house or its notarized copy, as well as some other documents.

If you know how professionals cut into a gas pipe and think that you can do this work yourself, get the necessary materials. But be aware that an unlawful tie-in that entails the failure of a gas pipeline is punishable not only in administrative but also in criminal procedure. Two technologies are used to connect the new system to a working network.

Cold sidebar. At the same time, the main pipeline works in the previous mode: the supply pressure and the volume of blue fuel remain unchanged - the workers. This “scenario” is most often used to connect new users to the gas mains. Many "craftsmen" prefer just such an insert into a gas pipe under pressure, since its implementation technology is very simple.

Welding is the most common method of tapping into a gas pipeline

Welding. People call it the "traditional way." However, this time-tested reliable technique requires the contractor to have the appropriate qualifications and special clearance.

If we talk about the methods of insertion, then they are reel, implying docking to the ends of the working systems and Tauri. In the latter case, when inserting, the axes of the networks intersect.

Connection of a private house system with a gas pipeline

In order to make an insert into the highway, you have to perform the following activities:

• remove debris, rust, paint from the place of the intended connection;
• mark up. Where there will be an insert, mark.
• make holes. With the T-shaped method - two, with the reel - one;
• treat the cracks with clay.And start doing this while still dissecting the surface. This minimizes the risk of ignition / combustion of the gas. Close the finished holes as quickly as possible with a special plug made of clay and asbestos. Cool treated surfaces;
• install a trip device. Its installation is carried out after complete cooling of the metal in this way: open the plug and remove a fragment of the cut pipe. Then place the disconnecting device in the gap formed. It looks in the form of sticks of viscous clay, as well as a set of discs made of rubber and wood. When using the T-shaped method, there will be two slots.
• install the pipe. Through it, the gas pipe of a private house will be connected to the main highway. Before you make a hole in the plug and mount the nozzle, make sure that the diameters are correct: it is possible that the markings made earlier must be corrected. If this is not necessary, make a hole, install the pipe, weld the joints and close the valve located on the pipe;
• seal the holes and weld a new pipe. First of all, remove the metal residues that appeared during the making of the main gap. Then dock the pipe with the pipe, process with clay and brew. Use a soapy solution to check the tightness of the weld.

Finished pipe joints are checked for leaks using soap suds

Important! Welded joints and types of welds are strictly indicated by GOSTs applicable in our country. Therefore, it is necessary to carry out work only taking into account the requirements of these regulatory documents for these characteristics of the gas pipeline!

If the leaks are not fixed, proceed with the final work. By such is meant the backfilling of the trench. Despite the apparent simplicity, its implementation is also regulated by regulatory documents. They, in particular, stipulate that:

1. Around the tie-in unit, pipe and ball valve, soft soil is poured with a layer whose thickness should exceed 20 centimeters, after which it is compacted.
2. During the final filling of the soil into the trench and the pit with a bulldozer, the collision of such heavy equipment with the ground part of the ball valve, the tie-in unit and the pipes themselves should be excluded.

Upon completion of the construction, it is necessary to conclude an agreement with the regional gas service for the supply of blue fuel, as well as for emergency dispatch and maintenance. The gas pipeline is accepted by a representative of the same organization. Commissioning is necessarily completed by the preparation of a bilateral act with subsequent sealing of control equipment.