The article will talk about how the installation of internal gas pipelines of private households is carried out. And the most important step is crimping. This is the moment we will focus on. After all, it is with its help that you can make sure that the entire system is assembled correctly before connecting to the main gas line. With the help of control tests, you can identify the most vulnerable places, eliminate shortcomings in a timely manner and reduce the likelihood of an emergency during operation.
How technical verification is done
Control pressure testing must be done both before the launch of a new gas pipeline, and after the repair of the old one. Scheduled pressure testing should be carried out before the gas pipeline is put into operation. The same procedure should be repeated during a routine check of the status of the entire system. When conducting, you will be able to timely detect any, eventhe smallest defects found in pipes. As well as flaws that could be made when welding pipes.
Only after all deficiencies are eliminated, is it allowed to use the gas system. It is forbidden to carry out the installation of internal gas pipelines without pressure testing - a set of measures aimed at identifying shortcomings.
Before starting the procedure, it is advisable to check the technical condition of the gas pipeline. There are devices and instructions that will allow you to conduct an examination using technical means. The inspection must be carried out by a trained team, which has two operators, they will be able to examine and evaluate the condition of the entire insulation coating. A third specialist must fix the places where leakage is possible.
You need to examine not only the fittings and pipes of the main, but also all gas pipes, wells. In the process, you must make sure that there is no gas contamination. In the event that there is a leak, the gas pipeline must be declared emergency, and then proceed with troubleshooting. All these manipulations must be carried out during scheduled maintenance of the internal gas pipeline.
Rules for work
All operators who survey the highway must follow safety rules. In addition, special vests must be worn. This is especially true if work is carried out near highways. It is desirable that the intensitytraffic on the road was minimal at the time of all works.
In the event that the destruction of the insulation is detected, it is necessary to carefully examine the damaged area, and then make a verdict on the condition of not only the insulation, but also the gas pipe.
Careful examination of the pipe
It is possible that for a more thorough study will have to dig a hole. It happens that work has to be carried out in places where the infrastructure interferes with research using technology. In this case, it will inevitably be necessary to make a pit to make sure that the gas pipeline and its insulating coatings are not damaged.
Drilling a well is another way to examine the condition of a gas pipeline. Devices can be inserted into the hole to analyze the state of the air, as well as to detect a natural gas leak. When carrying out such activities, it must be remembered that the use of open fire within a radius of 3 m from the well is strictly prohibited.
Preparations
The most technologically advanced method of identifying design flaws is pressure testing of the internal gas pipeline. Before you start this procedure, you need to prepare. This is all done in compliance with safety regulations. First you need to study all the technical documentation that relates to the object of study. In this case, it is necessary to determine the location of the following elements:
- Plugs.
- Set of controlmeasuring instruments and automation.
- Set of special sensors.
- Compressor.
It is imperative to discuss the regulations of all procedures to be carried out with employees. All control measures before putting the gas pipeline into operation must be carried out with the employees of the gas facilities. The entire arrangement of the internal gas pipeline must be displayed on paper - it is precisely according to the plan that the pressure test is carried out.
The basis for the work and who performs it
To carry out pressure testing before launching the gas pipeline, you must have an application from the owner of the house or other object, the gasification of which is carried out. It is impossible to connect to the central gas pipeline on your own; all these works are carried out only by specialists from the gas service. Crimping should take place in the presence of several specialists:
- Gas workers.
- Representatives of those enterprises that carried out the installation of external and internal networks.
It is obligatory to have an executive drawing of the entire structure, which clearly indicates the laying of the internal gas pipeline and its connection to the main line.
Features of events
The activities must be carried out in full accordance with the operating instructions for the gas pipeline system. Before starting pressure testing, you need to blow the entire line with air to get rid of contaminants.
To launch a new gas network, it is necessarycarry out crimping, and the results must be successful. The procedure should be carried out under the guidance of one person. It is he who is responsible for the implementation of the work. It is worth noting that this person must have the appropriate qualifications.
It should also be noted that the responsibility for the removal and installation of all gas plugs lies entirely with the foreman of the gas section. This operation can be performed by employees who have the appropriate clearance, as well as qualifications above 4 categories.
What is done during the examination
Specialists who are responsible for pressure testing first compare the provided as-built drawings with the actual location of the gas pipeline elements. Needless to say, all data must match exactly. All equipment of the internal gas pipeline must be displayed on the drawing. After that, specialists perform a control inspection of all equipment, checking the correct operation of measuring devices.
After you need to make sure that all protective devices are working in normal mode, the alarm is connected correctly, the system is blocked in full accordance with the settings. It is also necessary to check the condition and operation of the heating boiler, burner, and other appliances.
All operations related to the control pressure testing of the gas pipeline must be formalized by issuing a permit order. It can only be issued to a specialist who hasrelevant qualification. Whoever accepts the admission-attire cannot.
Implementing tightness control
As soon as a satisfactory result is obtained according to the procedures that have been described above, you can start crimping work. To do this, the entire system must be connected to the compressor. All pipes are filled with air under a certain pressure. After that, the design should be examined for flaws. If any are identified, they must be eliminated immediately. In the same case, if the system is sealed, it can be connected to the gas line. When preparing, it is necessary to remove and install the plugs. All swivel elements can be replaced with threaded connections.
Press testing
And now let's look at what manipulations need to be carried out during crimping work:
- To disconnect the area to be treated from the main, it is necessary to close the valve and tap. If work is being done on the internal gas pipeline of the boiler house, then the high pressure valve and the low pressure valve must be closed.
- After closing the area, you need to install the plugs.
- If a flange breaks, shunt type jumpers must be used.
- To bleed the gas that is inside the system, you need to use a sleeve of a special design. It is made from fabric and rubber. Also, the operation can be performed using a candle installed on the condensate collector.
- Gas must be liquefied if it is not possible to do it as much as possiblesafe, it needs to be moved for storage.
- Install devices for connecting pressure gauges and compressor.
- If the system is extended, it is best to use additional hand pumps.
Control pressure testing of the external and internal gas pipelines is carried out at a pressure of 0.2 MPa. In this case, it is recommended to make the pressure limit no more than 10 daPa / h. These are the optimal parameters, but they can change - it all depends on where the work is being done.
It is worth noting that when performing some work on pressure testing of internal gas pipelines, it is best to use a pressure of no more than 0.1 MPa. As for non-industrial facilities, as well as a gas pipeline in residential buildings, control pressure testing should be carried out at a pressure of 500 daPa / h.
Results of work
In the event that the pressure in the system is stable during the entire time of control, we can assume that the pressure test has a positive result. When this situation is reached, specialists must remove the hoses that connect the air ducts to the system. In this case, it is imperative to monitor the condition of all shut-off communications that are installed between the gas pipeline and the air duct. After that, it is necessary to put plugs on the fittings.
If stable performance is not achieved during crimping, the result is negative. In this case, it is necessary to perform a complete technical study of the entire system in order to find flaws and get rid of them. BUTafter that, the whole procedure is repeated to make sure that all the work done is done correctly.
Pressure testing is completed only after the pressure in the entire system is stable. If the status check fails, you will not be allowed to connect to the trunk. A refusal to connect to the highway can also be obtained if there are violations that are allowed during pressure testing.
Completion of verification work
After the pressure test is completed, the pressure must be reduced to atmospheric pressure. Then be sure to install fittings and equipment. After that, for about 10 minutes, you need to keep the entire system under pressure. To check the tightness at the joints, you need to use a soapy solution. When eliminating defects, you must first relieve the pressure to atmospheric pressure. The quality of welding work that was carried out after an unsuccessful pressure test must be checked using physical methods.
The procedure must be logged with all documentation. Upon completion of the inspection, the results of all work performed must be reflected in the acceptance certificate. This document must be kept with the rest of the documentation related to the gas pipeline. It should be noted that the results of pressure testing must be entered in the construction passport.
