Installing PVC drain pipes is a common project in home decoration or maintenance. Although it seems not difficult, if the details are not done well, it is easy to leave hidden dangers of water leakage and poor drainage. The following is combined with practical operation experience to teach you step by step to complete the installation. By the way, it is easy to step on pits.
Prepare the tools first: you need a steel tape measure (measure the length), a PVC pipe cutter (or a special cutter, which is more than the saw), a marker (draw the cutting line), a PVC special glue (buy it and match the pipe), sandpaper (polish the raw edge of the port), a pipe card (for fixing the pipe, divided into plastic and metal models), a level (measure the slope), and a ladder if it is an aerial work.
The first step is to locate and put out the line. First determine the direction of the drain pipe - for example, the path from the sink, toilet or floor drain to the main drain pipe, and try to take a straight line with less turns (to reduce the risk of blockage). Then use a level to measure the slope: the PVC drain pipe is drained by gravity, and the slope should be 1% to 3% (for example, the 1-meter pipe should be 1 to 3 cm lower), otherwise the water will accumulate if it is not drained properly. For example, if there is 2 meters from the toilet floor drain to the main pipe, the end point should be 2 to 6 cm lower than the starting point. Use chalk to draw the location line of the pipe on the wall or ground.
The second step is to cut the pipe. According to the length of the line, use a marker to draw a cutting line on the PVC pipe. If you use a cutting machine, hold the pipe steady and cut it slowly to avoid edge collapse; if you use a cutter, turn and draw in circles until it is cut (don't use an ordinary saw, the incision is easy to oblique). After cutting, use sandpaper to polish the raw edge of the port smoothly - the raw edge will affect the bonding and sealing, and it is also easy to hang debris and cause blockage.
The third step is to deal with the bonding surface. First try to insert the pipe and pipe fittings (such as direct head, elbow, tee) to confirm that it can be inserted at a depth of 1/2 to 2/3 (don't insert it all in, leave a little space to avoid expansion and cracking). Then apply an even layer of PVC glue to the outer wall of the pipe and the inner wall of the pipe fittings - be careful to apply it all over and do not miss it. When applying, be fast, because the glue dries quickly (it needs to be connected within 10 seconds in summer).
Step 4 Adhesive connection. After applying the glue, quickly insert the pipe into the pipe fitting. When inserting, rotate it slightly by about 15 degrees (to make the glue distribute more evenly), and then hold it for 10 to 20 seconds without moving - this step is very critical, and it is easy to stick if it is moved. If it is a large-diameter pipe (such as more than 110mm), you can tie and fix it with a rope for a few minutes, and wait for the glue to cure.
Step 5 Fix the pipe. Fix the pipe to the wall or ground with a pipe card: install a pipe card every 1 meter for the horizontal pipe, install a pipe card every 1.5 meters for the vertical pipe, and install it within 30 cm before and after the turn. The pipe card should be tightened, but not too hard - the PVC pipe is brittle, and screwing it too tightly will deform the pipe. If it is a pipe buried in the wall or underground, it should be wrapped in cement or mortar first (but wait until the glue is completely dry before doing it, usually after 24 hours).
Step 6 Test for water leakage. After all interfaces are glued, be sure to do a water closure test: block the end of the pipe, fill the water from the top (such as pouring water into the floor drain), and observe for 1 to 2 hours to see if there is any water seepage. If it is a hidden pipe, you can use a pressure pump (hit 0.5 kg pressure), and the pressure will not fall off.
Finally, a few precautions: 1. PVC glue is volatile, open the window for ventilation during operation, don't smell it close; 2. Don't let the glue stick to the skin when bonding - if it gets stained, rinse it with water quickly; 3. Don't press heavy objects in the pipeline (such as putting cement bags on it), it is easy to crack; 4. Try to leave an inspection port on the pipe fittings (such as installing a tee with a lid every 3 to 5 meters), in case it is blocked, it is easy to unclog; 5. During construction in winter, the glue can be soaked in warm water for a while (not more than 40 degrees), otherwise the viscosity will become worse.
In fact, as long as the steps are solid, pay attention to the slope and bonding details, and the novice can install a non-leaking PVC drain pipe. If it is a high-rise or complex apartment, it is recommended to find a professional master, but the simple kitchen and bathroom branches are completely no problem - after all, it is more assured to install them by hand.