Installation of Metal Plastic Pipelines

     Today pipes made from polymer materials or with their usage are successfully applied in heating systems, as well as hot and cold water supply. In the modern market of engineering equipment, metal plastic pipes enter into competition with the product mentioned above. It is impossible to state the unambiguous priority of the latter, though it is quite known that for a number of reasons, including psychological ones, Russian customers more often give preference to the “metal” one.
     One of the most important characteristics of metal plastic pipes is their processibility during installation. They easily bend, they do not demand exact fitting of the linear sized, and without any help of additional tools they preserve the form given to them by the installer.
     The peculiarity of a metal plastic pipe conditions the necessity to treat it carefully and strictly observe installation technologies. It is especially important as in the majority of cases rules demand hidden installation of metal plastic pipelines, when bad hermiticity is extremely undesirable.  

     Connection Types 

     A large variety of formed components for metal plastic pipes is presented in the market today. Speaking of the method of connections to pipes, it is advised to divide all the fittings into screw (tread) and pressing (press-fittings).

     In the first case, the connection is established by means of pressure that appears in the result of screwing the nut on the open blooming ring. The device of one of the screw fittings is shown in the picture. For hermiticity, its cap has got a special deterrent profile with radial notch and two seal rings that are in close touch with the pipe. A special cushion serves the purpose of tight connection between the fitting case and the cap. One more cushion is placed between the cap and the pipe end surface. This element excluding the possibility of a direct contact between the aluminium layer and the metal of the fitting and thus preventing electrochemical corrosion is usually made from teflon. Teflon cushions are aslo recommended as seals. 

     As has already been stated, screw connection installation does not require a special tool: it is realized by with the help of two wrenches (one is used for screwing the nut, the second is used as a counteraction). In order to facilitate the seal ring installation and to prolong the fitting service life, silicone lubricant is applied. Here it is forbidden to use mineral oils or other petroleum derivatives. Usually lubricants are included in the assortment of products manufactured by metal pipe producers.

 For the installation of single-layered pressure pipes PPR, PE and metal plastic pipes PPR-AL-PEX, it is necessary to follow the exact procedure and make use of appropriate instruments. NewPlast Company offers a pipe cutter, calibrator and welding machine. The quality of pipe connection depends on how strictly orthogonally to the pipe axis the cutting is made. The pipe cutter is used exactly for making an accurate cutting. Polypropylene pipes are harder than the polyethylene ones, and the systems from them are constructed with the help of fittings: angle bars, breechings, etc. These systems are non-detachable. The application of polypropylene and polyethylene pipes reduces the installation time for 2-4 times, as well as decreases the cost value of the pipeline for 30% in comparison with the metal plastic one.
       Pipeline installation is carried out by means of diffusive connection under exposure to a high temperature which makes it possible to create an absolutely firm homogeneous connection. The welding process does not require much time and consists of only three actions: cutting, heating, connecting. Moreover, the exploitation of the connection may start immediately after welding. The reliability of welding connections is much higher when compared to other types of connection.