Plastic pipe is lightweight, flexible, durable, and versatile. Products are made of plastics and composite materials, and used in many of the same applications as traditional metal and ceramic piping. Plastic pipe offers significant savings in terms of both weight and installation, however. Plastic piping comes in solid wall and corrugated configurations, and is available in a variety of common materials. Standards from organizations such as the Plastics Pipe Institute (PPI) specify which plastic materials are suitable for use in hazardous environments and fire protection systems. Specific applications for plastic pipe include fire water sprinklers, chemical fluid handling, natural gas distribution, potable water distribution, and floor heating systems. Plastic piping is also used in plumbing, drainage, and wastewater systems; and as culvert pipes and DWV pipes for drain, waste, and vent applications.
Common materials for plastic pipe include polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), and acrylonitrile butadiene styrene (ABS). PVC pipe provides good flexibility, a smooth surface, and nontoxic qualities. Because PVC piping is inert, some grades are used in food and chemical processing. CPVC pipe shares many of the same advantages and uses as PVC, but typically carries higher temperature ratings. HDPE pipe provides good temperature resistance and is used in drainage structures and systems. LDPE pipe is used in drainage systems as well as industrial process components, laboratories, and sprinkler and drip irrigation systems. ABS pipe provides good chemical and creep resistance as well as dimensional stability. Other types of plastic pipe are also available.
Plastic pipe is available in both English and metric sizes. Wall thickness may be specified numerically, or defined according to a pipe schedule. The American National Standards Institute (ANSI) assigns pipe schedule numbers to classify wall thicknesses at different pressures. Other specifications for plastic pipe include section shape, maximum pressure, and temperature range. In terms of features, plastic pipe may provide abrasion resistance, biological resistance, or chemical resistance. Products are also described as lightweight, nontoxic, and low maintenance. Easy identification, the ability to use plastic pipe with a variety of joining methods, and the low thermal conductivity of plastic piping are some additional benefits.