Plastic pipe is cut by various types of saws. Band saws make reasonably straight cuts. However, band saws are not easily transported to work sites. Hand saws are capable of cutting plastic pipe, but require substantial effort to make straight cuts that are perpendicular to the axis of the pipe. Hand saws are also slow. Powered portable saws of various types are available on job sites. These power saws are generally fast, but make cuts that are not square with the axis of the pipe.
Plastic pipes are used in water supply systems and sewer systems. Water systems and sewage systems both employ plastic pipes with relatively thick walls. Plastic pipes with thick walls are connected together with molded couplings and fittings such as elbows and tees, and adhesives. These fittings generally have internal projections that limit the distance the end of a pipe can be inserted into the fitting. If the cut end surface of a pipe is not in a plane that is perpendicular to the pipe's center line, portions of the end of the pipe cannot be inserted as far into the fitting as required to form a strong joint without leaks. Weak joints may leak the first time they convey a fluid. There is also a chance that weak joints will hold fluids initially but fail later. Unexpected failures and leaks may cause substantial damage.
Plastic pipes are also used for pneumatic systems. These plastic pipes generally have relatively thin walls. Plastics used to make such pipes are semi-rigid. Like the thick walled pipes, molded couplers and fittings are used. Adhesives secure the pipes to the couplers and fittings. Leaks in a pipe system for a central vacuum system, for example, will add air into the system, thereby reducing the effectiveness of the system. Such leaks in a vacuum system are difficult to locate, even if the pipes are accessible. It is therefore imperative that strong joints without leaks be formed.