Uses of Plastic Pipe
Many of today's plastics were developed during and just before World War II. Some were introduced into piping systems in the 1930's. In the United States, plastic piping systems obtained wide acceptance in the late 1950's and early 1960's. Since then plastic pipe usage has increased at an astounding rate.
Water mains, hot and cold water distribution, drain, waste, and vent (DWV), sewer, gas distribution, irrigation, conduit, fire sprinkler and process piping are the major markets for plastic piping systems throughout the world. Underground piping makes up the largest part of the market.
Plastic piping systems enable many important sustainable and green technologies for buildings. To learn more about this important subject, please download our green applications report here.
The primary plumbing applications in which plastic piping is used:
- Building Drain, Waste and Vent (DWV)
- Building Sewers and Drains
Besides offering low installed costs, plastic pipe is attractive for non-pressure applications (DWV and sewer) because the smooth inner walls assure high gravity flow rates and minimize the chances of developing stoppages. Plastic sewer pipes have adequate strength for earth loads and high chemical resistance, which means long life when used for sewer installations.
ABS, PVC and PE plastic pipe materials are used for these applications. There are separate ASTM standards for each plastic pipe based on material, dimensioning system, application, and (sometimes) sizing.
ABS and PVC piping have been used for many years in residential DWV systems where intermittent temperature excursions up to 180°F for ABS and 140°F for PVC can occur.
- Water Service
- Hot and Cold Water Distribution
Plastic pressure piping is used for many industrial processes, in heating and cooling systems, fire protection installations, gas distribution, and for water supply and distribution.
Potable water applications include cold water services from wells or water mains up to the building as well as hot and cold water distribution piping within buildings.
ABS, PE and PVC materials are all available with 73°F stress rating for use in pressure piping. PE piping is used extensively for cold water service lines and water distribution systems outside the building. Its low temperature flexibility make it especially suited for use in applications where temperature of 35°F and lower will occur.
The maximum temperature at which PE has an HDS rating is 140°F.
Materials with HDS Ratings for Higher Temperatures
Chlorinated Poly (Vinyl Chloride) (CPVC), and cross-linked polyethylene (PEX) materials are available that are rated for long term service at 180°F as well as for cold water applications. Hot and cold water distribution system piping made from these materials has a working pressure rating of 100 psi at 180°F. These systems are tested at 150 psi at 210°F for at least 48 hours to assure integrity at those condition, which may develop in the event the water heater controls malfunction. Thus, such materials are suitable for hot water distribution where water heaters are installed with relief valves set at 150 psi, 210°F.
All plumbing codes require the use of piping having the 100 psi @ 180°F rating for both the hot and the cold water portions of the water distribution system.
Some other applications
- Fire Sprinkler Piping
- Swimming Pool Piping
- Chilled Water Systems
- Ice Melting
- Radiant Floor Heating