Mounting and joining of sewer plastic pipes.
In principle, you can mount the pipeline in a variety of ways. This can be a welded joint, or a bell joint. Also, a threaded joint is often used( it all depends on the circumstances and the environment where the installation is performed).
As for construction materials, among them are the following:
- alloys;
- metal;
- polymer compounds.
In this case, the polymeric docking includes:
- polyvinyl chloride;
- polypropylene.
Under the metallic material, we understand the pipeline made of cast iron or steel. 
In this article we will talk about PP-B and PVC-type sewer networks. To date, for them, there are only three installation technologies: welding, socket and threaded coupling. Naturally, each of these technologies differs from each other, for each of them there is specific equipment, manipulations, couplings and communications. In this regard, we will consider the installation for each connection separately.
Welding technology.
Recently, specialists have started using diffusion welding for structural materials from polypropylene. Cold welding technology is used for PVC pipes.
Initially, consider the situation with a pipeline of polypropylene.
Before joining such pipes, cut the end of the pipe and measure it in the coupling. These two operations are very important, because in the future, the quality of the installation will depend on them.
Now, take a special soldering iron. It is needed in order to heat up the coupling and the pipe. For this, put these items on the nozzle and warm the device to 260 g.on C. 
When this operation is complete, remove the heated part from the guides, press the pipe into the coupling where you have set the marked depth. Once the seams have cooled to about room temperature, the docking can be considered successful and ready for use.
Now, let's talk about installing a pipeline of PVC.
The work is very similar to the previous one. You also need to cut the butt and make a measurement of the depth of immersion. Then, it is necessary to apply to the outer part of the pipe and the inside of the coupling the glue recommended for such work. Already at the very end, the pipe is inserted inside the coupler to the marked depth and slightly scrolled. After processing the seam with glue, after several hours the ready-made joint can be operated.
Technology "in the socket".
As already mentioned for different mounting, a different order of actions. For docking in the socket it is next.
You need to take the bell and place it in the opposite direction, relative to the flow, then fix the first product on the supporting surface. Now, take up the O-ring and insert it into the socket of the receiving pipe. After this, lead the smooth end of the second pipe. Lubricate the elements with a normal soap solution. This will make the installation process easier. Once the connections are complete, secure the second pipe on the support surface and start everything from the beginning.
Do not forget that this installation is possible only in the construction of non-pressure networks. 
Technology "on the coupling".
If the diameter of the pipeline does not exceed 63mm, then use the pipe joint on the coupling safely. It is convenient and practical, especially when installing taps for pallets, sinks, etc.
To begin with, take up the dismantling of the fastener, and then connect the plastic sewer pipes with a threaded coupling. After that, take the O-ring and the lock nut, put them on the pipe and insert it into the socket of the coupling. At the end, screw the lock nut onto the threads of the coupling end. Everything - docking is ready for operation.
In brief, it is worth mentioning the welded joint of a steel pipeline. For this you will not need any fittings, couplings and tees. It is necessary to have electric or gas welding in order to carry out the welding seam, which will connect the communications. When the sewer pipeline has a large diameter, it is joined using a welding machine. Well, and if the pipeline has a diameter in the range of 50 to 150 mm.(ie, it is small-sized), it can be brewed by hand.
