One, [anti-seepage sealing treatment]
According to the China engineering construction standardization association standard issued by the 8 C E C S 1 1 0 0 5 steel mesh skeleton plastic (PE) pipe water pipeline engineering technical regulation 5.3.5 regulation: "pipe fused connection shall meet the following requirements: no surface coating of the end face of bare wire, should be impervious seal processing." If not processed, there may be outer rupture or bulging phenomenon, resulting in the end face "channeling water".
Ii. [Pipe parts are strictly prohibited to operate with water]
Common water violations are as follows:
1. Use a wet towel to wipe the dirty and impurities on the surface of the pipe and parts, and then residual water in the matching use;
2. The case that the pipes and parts are connected in the rain without protection;
3. The construction environment causes water sputtering to the surface of pipes and parts, which is not dried in time.
Consequences: After welding pipes and parts with water, it is easy to appear the situation of virtual welding disconnection in the test process. It is found that there are traces of pores on the welded surfaces of pipes and parts, and the air pressure on the welded surfaces is caused by water vapor in the welding heating process, which seriously affects the welding quality!
Iii. [Improper scraping of oxide layer of pipe]
Common violations are as follows:
1. The oxygen layer on the surface of the tube is not scraped;
2, make use of grinding machine into the scraping situation.
Have consequences:
After the pipe production line is affected by air oxidation, the surface will become "smooth" (oxide layer), through experimental verification and combined with the construction situation, oxide layer directly on the pipe, welding surface caused by virtual welding effect, using the grinding machine to grind, with the pipe fast friction heat, easy to cause secondary oxidation.
Iv. [Pipes and parts fail to be inserted in place]
Common violations are as follows:
1. The pipes and parts cannot be inserted into the specified position;
2. The pipes and parts failed to be inserted with concentric circles, resulting in distortion.
Have consequences:
1. The socket of pipes and parts is not in place, which leads to the situation of empty burning of copper wire or extrusion of molten material and spraying material in the welding process, seriously affecting the welding quality;
2. The concentric circle socket is not inserted when the pipe parts are inserted, which leads to the extrusion of the molten material in the opposite direction of the force point during welding, resulting in the insufficient molten material at this position seriously affecting the bonding.
Five, [not according to the standard pressure test]
When the temperature is high, the steel wire skeleton pipe product is easy to absorb heat because of the black characteristics, the temperature of the pipe wall rises sharply under exposure, for a long time, the water temperature in the pipe rises significantly, thus causing the maximum working pressure of the pipe (MO P) to decline, such as failure to consider the impact of pressure medium temperature pressure, easy to burst the tube.
According to the provisions of article 5.1 pressure reduction coefficient in G B/T 3249-2015 Steel Wire Mesh skeleton composite Pipe:
Advice:
1, site pressure test can be arranged early, late or cloudy environment;
2, in strict accordance with the national standards for pressure test operation.
