Due to its strong corrosion resistance, wear resistance, non-toxic, flexible and alternative characteristics, PE pipe is widely used in water supply and drainage construction and gas transmission and other engineering fields.
HDPE pipe fitting suppliers This section describes the welding specifications for PE pipes
I. Welding requirements
1. Pipes, fittings and valves must be kept neat before installation.
2. The construction unit must carry out construction according to the design requirements.
3. Special machines and tools must be used when the heat melts.
4, the cut must meet the following requirements: smooth, smooth, no cracks, burrs, shrinkage, residue, etc.
5. Construction machines and tools, on-site water, electricity, materials, storage and additional facilities can meet the construction requirements.
Ii. Environmental requirements
1, the environment can adapt to the temperature between -5℃ ~ 45℃.
2, low temperature, take insulation measures.
3. When the wind is greater than level 5, take windproof measures.
4, in the hot summer, we should take shading measures.
5. Pipe fixers must be installed according to the spacing required by design.
Iii. Operation Specifications:
1. The power supply voltage of hydraulic system, milling system and heating system is 220V±10%, 50HZ AC. High or low voltage may affect the normal operation of the device.
2. After the temperature of the heating plate reaches the set temperature, it is better to wait 1-2 minutes for welding, so that the whole surface of the heating plate is more uniform.
3. When installing pipe fittings, the distance between the two pipe ports should be able to install the milling cutter, and there should also be a melting distance, so it is best to return the cylinder to the maximum stroke.
4. When the milling cutter and the heating plate are removed from the frame, the end face of the weldment should be avoided. After the heating plate is removed, the butt speed of the two pipes should be quick, otherwise the welding quality will be affected.
5. After the end face of pipe fittings is cut, the cutting surface should be kept neat, not to touch by hand, but not to touch oil, acid, alkali and other corrosive substances. More to keep the milling surface and heating surface neat.
PE pipe construction in winter, temperature below 0 degrees Installation requirements and methods:
1, low temperature anti-freezing: PE pipeline below 0 degrees in installation, pressure test, water will freeze the pipe, pipe fittings. It should be noted that no water should be accumulated in the pipeline after installation and pressure test, so as not to freeze the pipeline. Pay attention to pipe insulation.
2. Rain and snow weather: it will cause considerable difficulties to the construction, such as: ice on the surface of the pipeline, mud and water when defrosting. Avoid installing pipes in rain or snow.
3, low temperature welding: when the ambient temperature is below 5 degrees Celsius, there should be measures for welding: such as preheating and gradual cooling when installing pipes, so as to avoid pipe cracking and other phenomena.
4, strong wind: winter wind will produce numerous problems, strong wind weather should pay attention to the transport pipeline and loading and unloading pipeline, transport pipeline in strong wind weather, should be careful driving, the pipeline fixed safely, in the loading and unloading pipeline, should constantly pay attention to the safety of loading and unloading, to avoid unnecessary losses.
5, low temperature weather: low temperature construction personnel safety problems: when the temperature is low, people will add clothes to keep warm, but wear extra clothes and cold make the body stiff, awkward action. Staff should always pay attention to keeping warm and careful, pay attention to their own safety.
6, pipeline protection: in winter, moving the pipeline should be extra careful, the cold weather PE pipe is easier to crack, can not make PE pipe fall from height or be hit by heavy objects, more can not be forced to fold, to avoid pipeline fracture.
Precautions for welding in winter
1. The welding temperature of PE pipe is 220±10℃. Due to the low temperature in winter, the temperature can be set at 230℃. If the wind is strong in winter, it is necessary to cover the two ports of the pipe with plastic sheets to prevent "drafts". At the same time, a tent is set up to avoid reducing the melting temperature of the pipe due to the wind, which can not be glued together.
2. Heat absorption time According to the company's "PE Construction Disclosure Book", the winter temperature is low, and the heat absorption time can be properly increased according to the pipe melting situation.
3. The cooling time shall be carried out in strict accordance with the construction disclosure book. The pipe shall not be moved before cooling to avoid the fracture of the pipe at the welding place.
Special attention will be paid to:
1. The depth of the buried pipe must be below the frozen soil layer. If some parts are shallow buried, moderately lift some soil covering.
2. In winter welding construction, we must pay attention to keeping the welding interface warm and windproof. If necessary, we should set up a tent and keep the temperature in the tent at about 5℃.
3. Shorten the time from removing the heating plate to connecting the pipe port as often as possible to prevent the molten port from cooling quickly in the air and curing the surface.