The first is the preparation work before construction. Check the quality of pipes and fittings first: the pipes need to be free of cracks, dents, bubbles, and uniform wall thickness; the sockets and sockets of the fittings should be smooth and burr-free, and the size should match the pipe. In terms of tools, you need to prepare a hacksaw (or special cutting machine), tape measure, level, brush, PVC special adhesive, etc. Before construction, you must also check with the design and civil construction party to confirm whether the pipeline direction and elevation avoid load-bearing structures such as beams and columns, and avoid later modification.

Next is measurement and release. According to the design drawings, use ink lines to pop out the center line of the pipeline to determine the position of the vertical pipe and the horizontal pipe. The slope of the horizontal pipe is the key - the slope of the domestic sewage pipe is generally 0.026 (26mm drop per meter), and the rain pipe is 0.015. It must be checked with a level meter. The slope must not be reversed, otherwise it will lead to poor drainage or even blockage.

Then there is pipe cutting and connection. When cutting the pipe, the hacksaw should be straight, and the cut of the cutting machine should be flat to avoid burrs. Before bonding, sand the surface of the pipe insertion end and the fitting socket with sandpaper to remove oil and dust; then use a brush to evenly apply PVC glue, which is thin and uniform so that it will not accumulate. When inserting, quickly rotate the pipe to allow the glue to be evenly distributed, and then maintain the axial pressure for 30 seconds to ensure that the interface is firm. The adhesive should be opened at any time, and do not let it solidify for too long.

The pipe should not be sloppy when fixed. The spacing of the riser brackets should not exceed 2 meters. The spacing of the horizontal pipe brackets is calculated according to the pipe diameter: the 50mm pipe should not exceed 0.5 meters, the 75mm should not exceed 0.75 meters, and the 110mm should not exceed 1 meter. The bracket should be fixed on the wall or floor with expansion bolts. It must be firm to prevent the pipeline from shaking.

Parts installation should pay attention to details. Tees and elbows should be concentric with the pipeline, and the interface should be firmly glued. One riser is installed on each layer of the inspection port, and one is installed every 10 meters for the horizontal pipe. Select the stairwell or the corner of the bathroom for good maintenance. The lid should be able to be opened flexibly.

Finally, the closed water test and finished product protection. After the pipeline is installed, the two ends are blocked and filled with water. The water level reaches the top of the riser or the highest point of the horizontal pipe If there is no leakage, it is qualified. After acceptance, wrap the pipe in plastic cloth to avoid cement pollution; if you bury it in the ground, lay fine soil first and then gently tamper it, don't let the stones break the pipe.

In short, every step of PVC drain pipe installation must abide by the specifications, from material inspection to closed water test, every link cannot be saved. Only by following the national standard can the drainage system be used for a long time and less problems.