The amount of plastic pipe in the world's utility infrastructure increases each year as new pipes are installed and segments of elderly pipe are replaced by pipe made of plastic. Most of the pipe transporting natural gas today is made of plastic. Drinking water and water used by industrial facilities and for commercial, agricultural and residential irrigation systems flows through plastic pipes. Sanitary storm water drainage systems use pipes made of plastic. Power and telecommunications and electrical cables are protected against damage inside plastic duct and conduit. Polyethylene (PE) and polyvinyl chloride (PVC) are the plastic pipes most often used for underground utility construction. Some in the PE market estimate that 90 percent of the natural gas pipe installed historically decade is PE pipe.PVC proponents claim that more linear feet of PVC water and sewer pipe is being installed today than all other types of pipe combined.
Thinking about plastic pipe wasn't available for utility systems until the 1950s, and it wasn't accepted for utility projects for several years after that, such wide acceptance and usage in a comparatively short span of time is truly outstanding.PE and PVC have several characteristics in common, but also significant differences. Both are light in weight, do not corrode and are resistant to chemical and bacteriological buildup. PE is more flexible than PVC. A primary difference is the way lengths of pipe are joined together and to other pipe materials. Compressed air or gases ought to not be introduced in to PVC pipes. The Plastics Pipe Institute (PPI) represents manufacturers of PE pipe and actively promotes the use of PE products. The Uni-Bell PVC Pipe Association does the same for member companies who manufacturer PVC pipe. The sections that follow summarize characteristics of the two types of pipes and are based on information provided by the two associations.
"PVC pipe entered the buried pipe market to solve chronic issues in the water and wastewater industries," says Craig Fisher, P.E., Uni-Bell technical director and western regional engineer. "PVC gained acceptance by being better than the existing options, and PVC grew to dominance with its enviable performance record."
PVC is widely used for:
Corrosion resistance, life expectancy and durability are primary reasons PVC is chosen for water systems. In the sanitary sewer market, PVC's tight joints, flexibility, chemical resistance and immunity to corrosion make it ideal for this challenging application.
PVC pipe is simple to handle, install and repair. It is environmentally friendly, will seldom rust or rot, resists buildup of chemicals and harmful bacteriological deposits and maintains excellent flow characteristics. PVC pipe is widely accepted by industry and regulatory agency codes. PVC product standards (AWWA C900 and C905) require a pressure check on each piece of pipe. PVC accommodates expansion and contraction every 20 feet at the gasketed joint.
PVC is manufactured by extrusion in a variety of sizes and dimensions and usually sold in several lengths and diameters ranging from 1/2-inch to 60 inches. Pipe segments are quickly connected by gasketed joints. PVC pipe is manufactured to conform to various standards for both pressure and non-pressure makes use of. PVC has greater tensile strength than PE.
Although there is no universal color-coding standard, PVC pipe can be manufactured in a variety of colors which frequently are used to identify the way it is used. Colors often used to identify applications include white, blue, and dark grey for cold-water pipe; green for sewer lines, dark grey for industrial pressure systems, purple for reclaimed wastewater, and white for drain-waste-vent pipe and some low-pressure piping.
PVC is not recommended for conveying compressed air or gases, and compressed air ought to not be used to check PVC pipe.Polyethylene (PE) Pipe PE pipe is used for a variety of applications, including distribution of pressurized natural gas, pipelines carrying petroleum and petroleum products and chemicals, underground loops for geothermal heating and cooling systems, distribution of compressed gases and air, potable water mains and service lines, and sanitary and storm sewer systems. Corrugated PE pipe is used for storm sewers and highway drainage systems.