Polyethylene pipes and tubing are very flexible but tough. Pipes and tubing made out of polyethylene weigh very little compared to piping and tubing made out of other materials such as iron and stainless steel. Temporary water lines, dredge lines, slurry transport lines and bypass lines are often constructed out of polyethylene. Oil and gas collection pipes and tubing are also often created out of polyethylene. Polyethylene tubing is relatively easy to install because it is flexible and very light.
Polyethylene tubing is only recommended for use under pressure in applications within a specific range of temperatures. Approximately -40 degrees Fahrenheit is the lowest temperature recommended for using polyethylene tubing, regardless of application. About 140 degrees Fahrenheit is the highest recommended temperature for using polyethylene tubing. For non-pressure applications, the maximum allowable temperatures for polyethylene tubing slightly increases. Polyethylene tubing can be used in non-pressure environments where temperatures reach 180 degrees Fahrenheit.
Temperature affects the overall tensile strength (amount of stress a material can take before breaking) of polyethylene tubing. In general, lower temperatures cause polyethylene tubing to increase overall tensile strength. Higher temperatures cause polyethylene tubing to decrease overall tensile strength. At 73.4 degrees Fahrenheit, polyethylene tubing's tensile strength is about 2,800 pounds per square inch (psi). At 110 degree Fahrenheit, the tensile strength of this type of tubing is closer to 2,000 psi. Polyethylene tubing's overall tensile strength is approximately 1,450 psi at 140 degrees Fahrenheit.
While most polyethylene tubing is ideal for outdoor use, some types of polyethylene tubing are not rated for use outdoors. Outdoor tubing can be exposed to weather extremes. Temperature and pressure fluctuations throughout the year can wreak havoc on polyethylene piping and tubing. Consumers should make sure that they are using polyethylene tubing with the proper rating for their environment. Polyethylene piping and tubing for underground applications does not experience much temperature fluctuation and remains largely unaffected by outdoor temperature changes throughout the year.