Because the overall length of PE pipes is not cut after production, it is also convenient for future construction and use. And during the construction of PE pipes, suitable docking techniques will be used for pipe laying and docking work, followed by the use of pipes. However, if the docking techniques are not done well, it is very easy for the pipes to break during your use, which not only affects your use but also makes maintenance very troublesome.
We take the joint construction of electric heating fusion welding as an example to understand the docking of PE pipes:
1. Firstly, it is necessary to clean the inner and outer surfaces as well as the end faces of the pipe joints. It is recommended to use a specialized non-metallic pipe cutter for processing. The cleaning length should be greater than the length of the inserted pipe fitting, and the pipe end should be cut flat; Ensure that the aging layer and contamination layer on the outer surface of the joint are completely removed. The blade of the specialized planer is serrated;
2. The outer surface (fusion surface) of the pipe joint should be scraped off with a special tool to remove a thin layer. After disposal, the outer surface of the pipe joint will form fine thread like circumferential scratches, which should be sealed and packaged with plastic film; If the pipe joint cannot be welded immediately after planing to prevent secondary pollution. Before welding, the outer surface of the pipe joint should be wiped with a cleaning tissue provided by the manufacturer. If the joint after disposal is left for a long time, it is recommended to remake the joint during formal connection. Considering that planing reduces the thickness of the pipe wall, it is recommended to cut off the original planed joint when remaking it. It should be opened before use, and the inner surface of the pipe fittings should also be wiped with the same cleaning tissue before use after opening.
3. Pipe fittings are usually sealed in plastic bags. And fix the welding joints with pipeline clamps to prevent eccentricity or vibration damage to the welding fusion. The pulling depth of each joint is the length from the pipe socket to the internal protrusion or half the length of the pipe clamp. A gap of 510mm should be left between the joint and the protrusion (or between two joints);
4. Insert the two processed pipe joints into the fitting to prevent the expansion and elongation of the pipe joints during welding heating from pushing each other and damaging the fusion surface. Mark the insertion depth on each joint. Start welding equipment;
5. Connect the welding equipment to the electrode of the pipe fitting and input the welding heating time. Start welding until the welding machine stops heating at the set time. Generally, each pipe fitting comes with a card that records the required technical parameters such as heating voltage, heating time, cooling time, etc. Generally, there are two plastic buttons of different colors on the pipe fittings, which will gradually jump up during the heating process. When the heating time is halfway through and the heating is almost complete, the button will completely jump up to indicate that the heating process is about to end. After the heating process is completed, it takes a few more minutes for the outer surface temperature of the pipe clamp to reach the high temperature effect; At this point, it is important to note that the welded joint begins to cool down. During this period, it is strictly prohibited to move the vibrating tube. Actually, due to the low thermal conductivity of PE materials. Please be careful to avoid burns.
When connecting PE pipes, it is necessary to confirm their construction quality multiple times, because if the pipeline is disconnected during buried pipe construction, it will need to be rebuilt, which will not only affect your normal use but also cause damage to the pipeline.