Apparatus for welding polyethylene pipes.
From the school course, many remember that high and low pressure polyethylene refers to thermoplastic polymers and, as the melting temperature increases, begins to lose ties in the polymer chain. At this stage, it is possible to mix together the molecules of the two polymer materials, and upon cooling to obtain a compound that by its characteristics will be equal to the qualities of the jointed parts. The melting point of polyethylene is low and, therefore, the time for welding work will go very little. It all depends on the thickness of the pipes to be welded, and the joint will withstand loads at the level of intermolecular bonds. 
As mentioned earlier - equipment for welding PE pipes is not a complex high-tech design. In fact - this is the same soldering iron, with which you need to heat the product to the melting point, and it does not exceed 270 ° C for polymers. The set of equipment includes a set of nozzles of different diameters for supplying heat to the welding zone. The diameter of these tips should coincide with the diameter of the pipes to be welded. In addition, in the arsenal of any welder should be:
- measuring instrument( caliper, ruler, tape measure, etc.);
- sets of keys and screwdrivers for fixing the attachments and contacts of the electrical coupling;
- special tool - pipe cutter;
- reductant for the end of the pipe, the so-called calibrator;
- chamfering tool at the ends of the pipes to be connected.
As can be seen from the above, the installation for the welding of polyethylene pipes includes a very simple set of necessary equipment, which is in the "bins" of any good master
Various technologies for welding PE pipes.
If you ask the qualified specialists engaged in welding polyethylene pipes in Kazan, about the various methods of carrying out these works, we will get three methods:
- welding of polyethylene pipes to butt;
- docking in the socket;
- connection using an electrical coupling.
For any of the ways to mount a pipeline using a welding machine, a number of points must be considered in order to obtain excellent quality joints:
- Pipes for connection must be of the same manufacturer and be of the same batch. Then you are guaranteed to have the same chemical composition of the parts to be connected. Also it is necessary to take into account the thickness of the pipes that join. If this value is different for two products, there is a chance to "warm up" the element with wider walls, and as a result, the probability of obtaining a poor quality seam increases.
- Be sure to clean the ends of pipes from dirt, this will ensure sufficient tightness of the welded joint.
- Adverse weather conditions also affect the quality of welding. Such work should not be carried out in severe frost and rain, as the polyethylene is compressed from the cold, and this further prohibits electrical safety requirements, and the machine for welding polyethylene pipes is an electric appliance. Strong sunlight is also not needed when installing pipelines with welding equipment.
- wait until the weld has completely cooled down, so as not to disturb the polymer chain and interfere with the process of diffusion of polyethylene molecules.