Pipes made of PVC (white) and ABS (black) are both code-approved. One of the most important stages that is sometimes overlooked is beveling the inner and outside ends of the pipe. The interior bevel minimizes sharp edges that might trap dirt; the outer bevel is essential for streamlined assembly and leak-free connections. Both bevels should be at least 1/4 inch deep.
The benefits of beveling your pipes include improved air flow, which reduces the risk of explosions; minimized trapping of dust, dirt, and other contaminants; and increased resistance to chemicals and heat. Beveled pipes are also easier to connect together than non-beveled pipes. Without a bevel, the ends of two pipes cannot be joined securely, so couplings or fittings are needed. This can increase the cost of building projects significantly.
PVC and ABS piping is available in various sizes, shapes, and colors. It is usually priced by diameter, with 12-inch lengths being the most common size. Heavier duty versions of PVC and ABS may be used in applications where high temperatures are present. These types of pipes are more resistant to heat and damage from contamination.
PVC and ABS piping is very affordable, but it does require some care to look after properly. All piping should be treated with an anti-corrosion primer before painting or coating any component of the project.
PVC pipe is recognized as an appropriate material for DWV, sewage, and potable water services and distribution in all model plumbing codes. It is also used for outdoor faucets and other fixtures.
The primary advantage of using PVC pipe is its ease of fabrication with various fittings available for making connections between pipes. Also, its transparency allows you to see what's inside the pipe while it's being installed. The most common size of PVC pipe is 2 inches in diameter, but 4-inch and 3-inch versions are also sold commercially.
As long as you meet code requirements, you can use any type of fitting to connect pipes together. But if you want to be sure that they're compatible with each other, check the fitting catalog of any major plumbing supply company. They should have pictures of each possible combination so you can choose the right one for the job. For example, some PVC joints are not designed to accept compression fittings, so make sure to use those types that are.
Also note that if one day you decide to replace the piping in your home, this work cannot be done without first cutting away the old pipe (carefully remove any old insulation too). Then, install the new pipe and finish the connection either by welding or by covering the joint with solder.
PVC pipes come in white or dark gray. Colors of CPVC include off-white, light gray, and yellow. Technical details are provided on the side of both pipe types for simple verification. Pipes are identified by size, usually from 1/4 to 4 inches in diameter. The size indicates how many gallons can be placed in that line of piping.
The type of pipe used for your project will depend on how much water you expect to use and where it will go. If you're installing new plumbing for a house with several bathrooms, for example, then you should use larger pipe. Also called "drinking water service," this type of pipe can handle up to 120 degrees Fahrenheit water without breaking down. If your house has one bathroom, then 3/4 inch pipe will do.
If you plan to simply drain your pool then 5/8 inch CPVC pipe will work just fine. Or if you're just running some sprinklers outside then 3/4 inch CPVC pipe also works well for that purpose. But if you need to run water through your pipe for any reason (such as taking a shower) then you should use larger pipe. The size designation tells you exactly how big a hole each piece of pipe needs to have drilled before it can be inserted into the next piece of pipe.
Temperature differences above and below the installation temperature cause length changes in ABS, PVC, and CPVC pipe, as well as other pipeline materials. They expand and compress at a rate that is 4.5 to 5 times that of steel or iron pipe. The maximum average linear expansion of PVC pipe is 0.5 in (12 mm) per foot (300 m), but some brands may be made from material with less expansion.
Pipe manufacturers specify the maximum allowable strain for each size. This is called "Elongation" and it's shown on the label or packaging inside the pipe. For example, a pipe labeled "Elongation: 50% - 100%" means that under normal conditions of use and storage, the pipe will not stretch longer than half its installed length or not more than 100 percent of its original diameter. Pipes used for drainage or water supply should not stretch more than their specified limit, because they need to be able to absorb movement caused by earthquakes or storms without breaking.
The actual strain experienced by a section of pipe depends on how it is used. If a pipe is rigidly fixed at both ends, it will experience only compressive stress due to weight forces. If a pipe is not fixed at both ends, it will experience tensile stress as well as compression. Weight forces are evenly distributed along the entire length of a rigidly fixed pipe.
Bending clear PVC tubing may be beneficial in some situations requiring long radius bends and odd designs. The temperature required to heat the pipe is determined by the pipe size and the severity of the desired bend radius. Smaller diameter pipes require more heat to soften them enough to bend without breaking.
There are several methods for bending PVC pipe. The easiest and fastest method is to use a hand tool called an acrylic wedge. These tools are available at any hardware store for around $10-$20. To use an acrylic wedge, first mark each end of the tube about 1/4 inch from the edge. Then, using cold water, slowly work the plastic into a gentle curve just like a pie crust. Let it sit for a few minutes then repeat with a hot tap. It may take several attempts to get it right the first time. Once the pipe is bent, it should hold its shape until heated again to bake it hard.
For larger curves or if you don't have access to an acrylic wedge, there are other options. A metal bending brake can be used instead. These cost about $100 but they are very accurate and will not crack or break like an acrylic wedge would under the same conditions. They also can be used over a fire or even with a gas burner. Finally, if you have a drill press then you can use that too!