PVC sewage, its advantages and disadvantages
It has been more than 30 years since PVC was first tested as a material for sewer pipes. Probably, you will immediately have a question why the ubiquitous replacement of cast-iron sewerage, cumbersome and not particularly reliable, has not been carried out. But, it is necessary to recognize, the first experiments with PVC were not so smooth and not one year has been spent on creating an irreproachable technology for the production of high-quality PVC pipes. And then the test of time began, because it should be reliably know how long the PVC sewage system can last. The results proved to be more than satisfactory, the service life of pipes from the above material can be over 300 years if used carefully. This was clarified by a serious test, which was subjected to 200 millimeter PVC pipes, for which 135,000 cycles( which corresponds to 195 years) were driven away by sand. The thickness of the walls decreased slightly, only 0.118 of 2.05 millimeters.
The reliability of plastic sewerage is proven more than undeniable, it is also known that PVC perfectly withstand the direct ultraviolet radiation of , and, moreover, has a rather low coefficient of thermal expansion. However, one should not keep silent about some disadvantages of polyvinyl chloride. So, for example, low temperatures make PVC plastic brittle, so without proper insulation to lay sewage within the freezing of the ground is quite risky. What can we say about the transportation or installation of pipes from polyvinyl chloride in the frost. It should be noted and rather low heat resistance of PVC, long exposure to temperatures above 75 or short-term over 95 degrees Celsius can lead to the destruction of some sections of the pipe or fitting.
PVC is rather unstable before exposure to organic solvents, causing gradual corrosion of the walls with the appearance of a characteristic plaque, which, however, is less pronounced than that on cast-iron pipes.
PVC plumbing and its possible alternatives
The use of plumbing from PVC is extremely convenient - no matter what the diameter of plastic pipes for sewage, they have a fairly small weight and are easily interconnected by means of fittings of various modifications. By the way, about the diameters, there are many of them, ranging from 110 millimeters with a wall thickness of 3 millimeters, and ending with 500 millimeters with a wall thickness of 12.3 millimeters. For each pipe diameter, there are corresponding fittings: bends, tees, transitions, bends, couplings and plugs. However, with all the obvious benefits of using PVC sewage negative properties it is plentiful, so sometimes you can use alternatives to PVC.Close to the characteristics, however, with much less flaws, are pipes made of unplasticized PVC, otherwise NPVC, and plastic sewerage from polypropylene( PP).
It is noteworthy that the sewage from the NPVH is quite frost-hardy. In addition, it perfectly resists the effects of various chemical reagents, including solvents. Due to the fact that the hydraulic characteristics of plumbing products from the NPVH do not change under any conditions, this material produces an excellent pressure sewerage, which can even serve as a worthy replacement for steel pipes. When laying sewerage from the NPVC, a few people can raise a pipe of maximum diameter and the maximum possible length without difficulty, which makes it possible to abandon the use of construction equipment, except, perhaps, an excavator( a shovel is a bad competitor to a bucket for several cubic meters).Sewerage made of polypropylene is even more durable, and it is excellent heat-resistant and can withstand long-term exposure to temperatures exceeding 95 degrees Celsius. At low temperatures, the resistance to mechanical influences in polypropylene increases. The only drawback of PP pipes is that they do not withstand ultraviolet radiation.
Plumbing installation - extraordinary simplicity of connection
Sewer pipes are rarely purchased for stock, they are usually bought when there are problems that need to be solved. Therefore, there is to be an assembly, the complexity of which depends directly on the pipe material. If you have never done installation of cast iron sewage elements, you are very lucky, because it is quite difficult to connect fittings with pipes from this heavy metal. There are no sealing rings, it is necessary to work with a paste, clay and mastics, because of which there is always the possibility of an unsealed connection. It is another matter if it is necessary to install a plastic sewage system, be it PVC or polypropylene. Each pipe made of PVC or PP has at one end a bell that tightly surrounds the opposite end of the same pipe. It is enough to insert one pipe into another and complete the order. The fact is that inside the bell there are several annular ribs, between the extreme of which there is already inserted at the factory a sealing ring made of special rubber, which ensures a high-quality sealing. Many for strength use glue, applying it to the smooth end of the pipe, immersed in the socket.
If you are familiar with the sewage system, laying pipes is not very difficult, you just need to follow some rules. So, for example, taking into account the constant movement of large volumes of water from top to bottom in the domestic sewage pipes, pipes should be installed with the bell up. In general, the bell should always be turned against the movement of the drains, this will increase the sealing reliability of the joints and eliminate the possibility of blockages. Of course, silicone sealants can also be used for safety. In order to connect the plastic pipe with a metal of the same diameter, there are couplings. If it is necessary to join pipes of different diameters, special "transitions" should be used. Trenches for laying street sewerage, which is constructed of special pipes with thicker walls, should be digged taking into account the slope necessary for free flow of drains( from 1 to 45 degrees).However, if the trench suddenly turned out to be too deep, it is not enough just to raise its bottom by throwing excess soil. The land will necessarily take place, so the bottom must be poured with concrete and after the fact of its solidification start laying the pipes on specially sanded cushion on top. With due diligence, you will get excellent sewage.
