The article will talk about how the installation of internal gas pipelines of private households is carried out. And the most important stage is crimping. It is to this moment that we will pay all attention. 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 pipeline. With the help of control tests, you can identify the most vulnerable places, timely eliminate defects and reduce the likelihood of an emergency during operation.
How is a technical check performed?
Testing must be done both before the start of the new gas pipeline and after the repair of the old one. Planned pressure testing should be carried out before putting the gas pipeline into operation. The same procedure should be repeated during a routine check of the state of the entire system. During the process, you will be able to timely detect any, even the most insignificant defects present in the pipes. As well as flaws that could allow when welding pipes.
Only after all the deficiencies are eliminated, is it allowed to use the gas system. It is forbidden to carry out installation of internal gas pipelines without crimping - 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 instruments and instructions that will allow the examination using technical means. Inspection should be carried out by a trained team, in which there are two operators, they will be able to investigate and assess the condition of the entire insulation coating. The third specialist should fix the places where leakage is possible.
It is necessary to examine not only the fittings and pipes of the pipeline, but also all the gas pipes, wells. In the process, you must ensure 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 with the planned maintenance of the internal gas pipeline.
Rules for work
All operators who carry out inspection of the highway must comply with safety rules. In addition, special vests must be worn. This is especially true if work is being carried out near roads. It is desirable that the traffic on the road is minimal at the time of all work.
In the event that destruction of the insulation is found, it is necessary to carefully examine the damaged place, and then issue a verdict on the condition not only from the insulation, but also from the gas pipe.
Thorough pipe inspection
It is possible that for a more thorough study you will have to dig a pit. It happens that the work has to be carried out in places where the infrastructure interferes with research using technology. In this case, one will inevitably have to make a pit to make sure that the gas pipeline and its insulating coatings are not destroyed.
Drilling a well is another way to investigate the condition of a gas pipe. Instruments analyzing the state of the air, as well as detecting the leakage of natural gas, can be introduced into the hole. When conducting such events, it must be remembered that the use of open fire within a radius of 3 m from the well is strictly prohibited.
Preparatory Activities
The most technologically advanced method for identifying design flaws is crimping the internal gas pipeline. Before you begin this procedure, you must complete the preparation. This is all compiled subject to 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 position of the following elements:
- Stubs.
- A set of instrumentation and automation.
- A set of special sensors.
- Compressor
It is imperative to carry out a discussion of the rules of procedure for all the procedures that will be carried out with employees. All control measures must be carried out with the employees of the gas sector before the gas pipeline is put into operation. The entire device of the internal gas pipeline should be displayed on paper - it is precisely according to the plan that crimping is carried out.
The basis for the work and who performs them
To perform pressure testing before starting the gas pipeline, you must have a statement from the owner of the house or other facility whose gasification is carried out. It is impossible to independently connect to the central gas highway, all of this work is carried out only by specialists from the gas service. Pressure testing should take place in the presence of several specialists:
- Gas workers.
- Representatives of those enterprises that performed the installation of external and internal networks.
It is mandatory that there is an executive drawing of the entire structure, which clearly indicates the laying of the internal gas pipeline and its connection to the pipeline.
Features of events
Activities must be carried out in full accordance with the operating instructions for the gas pipeline system. Before you begin crimping, you need to blow the entire line with air to get rid of contaminants.
To start a new gas network, it is necessary to carry out pressure testing, and the results must be successful. The procedure should be carried out under the direction of one person. It is he who bears all responsibility 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 removing and installing all gas plugs lies entirely with the master of the gas section. This operation can be performed by employees who have the appropriate clearance, as well as qualifications higher than 4 categories.
What is carried out during the examination
Specialists who are responsible for crimping, first verify the submitted executive drawings with the actual location of the elements of the pipeline. Needless to say that all the data should match exactly. All equipment of the internal gas pipeline should be displayed on the drawing. After that, specialists carry out a control inspection of all equipment, and the correct operation of the measuring devices is checked.
After that, you need to make sure that all protective devices are working as usual, 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 devices.
All operations that relate to the control pressure testing of the gas pipeline must be formalized by issuing an admission order. It can only be issued to a specialist who has the appropriate qualifications. Anyone who accepts the admission order cannot.
Leak tightness control
As soon as a satisfactory result is obtained with the procedures described above, crimping operations can begin. 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 found, then they must be eliminated immediately. In the same case, if the system is tight, it can be connected to the gas line. In preparation, it is necessary to remove and install the plugs. All swivel elements can be replaced with threaded connections.
Crimping
And now let's look at what manipulations must be carried out when conducting crimping operations:
- To disconnect the section that will be subjected to the procedure from the highway, it is necessary to close the valve and the crane. If work is carried out on the internal gas pipeline of the boiler house, the high-pressure valve and the low-pressure valve are sure to close.
- After closing the area, plugs must be installed.
- If the flange breaks, then use shunt type jumpers.
- To vent the gas that is inside the system, you need to use a sleeve of a special design. It is made of fabric with rubber. Also, the operation can be performed by means of a candle mounted on the condensate collector.
- Gas must be liquefied, if it is not possible to do this as safely as possible, it must be moved for storage.
- Install devices for connecting pressure gauges and a compressor.
- If the system has an extended length, it is best to use additional hand pumps.
The control crimping of the external and internal gas pipeline is carried out under a pressure of 0.2 MPa. It is recommended that the pressure limit be made no more than 10 daPa / h. These are optimal parameters, but they can vary - it all depends on where the work is being done.
It is worth noting that when performing some work on crimping internal gas pipelines, it is best to use a pressure of not more than 0.1 MPa. As for non-production facilities, as well as gas pipelines in residential buildings, control crimping should be performed 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, it can be considered that crimping has a positive result. When this situation is achieved, specialists must remove the hoses that connect the air ducts to the system. In this case, it is absolutely necessary to monitor the status of all locking communications that are installed between the gas pipeline and the air duct. After that it is necessary to put plugs on the fittings.
If during crimping stable indicators are not achieved, the result is negative. In this case, it is necessary to carry out a full technical study of the entire system in order to find the shortcomings and get rid of them. And after that, the whole procedure is repeated to make sure that all the work performed is performed correctly.
Pressure testing is completed only after the pressure in the entire system is stable. In the event that the status check is unsatisfactory, you will not receive permission to connect to the trunk. A refusal to connect to the highway can also be obtained if there are violations that are allowed during crimping.
Completion of verification work
After crimping is completed, it is necessary to reduce the pressure to atmospheric. Then be sure to install fittings and equipment. After that, about 10 minutes you need to keep the whole system under pressure. To check the tightness at the joints, use a soap solution. When eliminating defects, you must first release the pressure to atmospheric. The quality of the welding work that was carried out after an unsuccessful crimping must be checked using physical methods.
The procedure should be recorded in the journal with all the documentation. Upon completion of the audit, the results of all work performed should be reflected in the acceptance certificate. This document must be kept with the rest of the documentation that relates to the gas pipeline. It is worth noting that the results of crimping must be recorded in the construction passport.