Irrigation systems in both residential and commercial installations radically improved with the advent of readily available piping and fittings, specifically designed for delivering water. A number of different types of irrigation pipe are now on the market, each with its specific uses and advantages. Knowing what is available can help you decide which pipe type is correct for any given application. There are three primary types of pipe that are strong, readily available and economical.
Polyethylene tubing, also referred to as poly pipe, is a black, flexible pipe for irrigation. The piping ranges in diameter from 1/4 inch to 2 inches. The flexibility of this type of pipe allows it to be mechanically pulled through the soil and enables it to be wrapped around curves very easily. The downside is that the wall strength of the pipe is not as significant as other pipe materials. Applications that work well with polyethylene tubing include bubbler, agricultural and drip irrigation systems. The tubing usually comes on rolls. Fittings for poly pipe are often assembled using metal or plastic bands.
Swing pipe also referred to as "funny" pipe, is also made of polyethylene, but has a much thicker wall to provide greater strength. This piping is used primarily to connect sprinkler heads to main lines of either poly pipe or PVC. The flexibility and strength of swing pipe will help prevent breakage of the main line, in the event that a sprinkler head is inadvertently run over. It also allows the installer to position the sprinkler better during installation.
This is a lightweight form of tubing made from polyvinyl chloride, or PVC. PVC in various schedules is widely available in most home supply stores. Schedule 40 is the most commonly used form of PVC pipe for irrigation and is commonly found in both residential and commercial applications. A wide variety of fittings, including elbows, connectors, reducers and angles are also available and are necessary to plumb a system, as PVC pipe is relatively rigid. For piping larger that 2 inches, CL 200 PVC is often used. PVC piping is assembled using a solvent glue and slip fittings or threaded fittings.