Now install the pipe metal simply uneconomical. Metal is more expensive than polyethylene, and is much less. In addition, requires systematic maintenance associated with the color of the outer surface and cleaning rust inside. In principle, one can not paint, but it is fraught with fistula in the pipes, and if the thin-wall pipe, then weld a fistula is problematic.
In place of metal pipes, PEX pipes came. Everyone knows that the guaranteed service life of such pipes is 50 years. These pipes are much lighter metal. Plastic pipes can be welded and check for leaks and hide in the thick wall and the wall display PEX fittings for connection, for example, tap in the bathroom.
Fittings for PEX pipes play a major role, because it depends upon the quality of reliability of the pipeline as a whole. Fittings for PE pipes play a major role, because it is on their quality depends on the reliability of the pipeline as a whole. Fittings are designed to connect plastic pipes in the field changes direction (rotation), the branching junctions of the pipeline valves in the field changes in the diameter of the pipeline. Fittings for PEX pipe are three varieties: Welded fittings, PEX fittings, cast and compression fittings.
Welded fittings are manufactured by welding elements (segments) of polyethylene pipes, ie, segments of pipes connect to each other by butt welding or electro-welding fittings and get the desired configuration. Typically, weld fittings (segmental type), they are called taps, there are the following varieties: Crossings, bends under 30, 45, 60, 90 degrees, tee at 90 degrees.
PEX Fittings for pipe, manufactured by injection molding, perform the same function as the welded fittings. They are made by casting, then processed by mechanical means. There are the following configurations: tee, the withdrawal of 90 degrees, the sleeve under the flange, transition and end cap.
Compression fittings for PEX pipes have one distinguishing feature: for their installation should not use any special equipment. While for the installation of pipelines with welded and cast fittings necessarily require soldering.
Compression fittings need only connect with the pipe and tighten it by hand. All installation is over, the connection is very reliable and capable of withstanding the pressure to 16 atmospheres. Also, these fittings for PEX pipes can be used repeatedly, such as changing the location of pipelines.