Construction plan of indoor dark application of PVC drain pipe: anti-blocking and sealing guarantee

the indoor drainage system is an important part of the building function, PVC drainage pipe is widely used in the dark application project due to its advantages of light weight, corrosion resistance and convenient construction. However, if the anti-blocking and sealing design are ignored in the dark application construction, it is easy to lead to hidden dangers such as pipeline blockage and leakage in the later stage, which is not only difficult to maintain, but also may cause serious problems such as wall mildew and structural damage. Combining construction specifications and engineering practice, this paper systematically expounds the anti-blocking and sealing guarantee scheme of indoor dark application of PVC drainage pipe from the dimensions of material selection, node treatment and construction technology.

Material selection and pretreatment control

The anti-blocking design of the dark application drainage system needs to be controlled from the source. The pipe should be made of UPVC drain pipe in line with GB/T 5836.1 standard. The diameter of the main riser pipe is not less than 110mm, and the diameter of the horizontal branch pipe is determined according to the calculation of drainage equivalent. For example, the branch pipe in the bathroom shower area is not less than 75mm, and the branch pipe shared by the washbasin and the washing machine should be De50 pipe diameter. The appearance of the pipe should be checked before entering the field to ensure that there are no cracks, depressions, flat ports, and uniform wall thickness. When cutting the pipe, use a special pipe cutter to ensure that the incision is perpendicular to the pipe axis and avoid burr residue. After cutting, the port needs to be sanded with sandpaper to prevent the water flow resistance from increasing and forming sedimentation.

Scientific layout of drainage slope and path

The slope design of the drainage horizontal pipe directly affects the anti- During construction, the design specifications should be strictly followed: the slope of the cast iron pipe for domestic drainage is 2%, and the slope of the UPVC pipe should be 2.5% to 3% to ensure that the water flow rate reaches more than 0.6m/s to form a self-cleaning ability. The installation path needs to avoid sharp bends and frequent direction changes. The length of the transverse branch pipe is controlled within the scope of the specification (for example, the branch pipe of the washbasin does not exceed 1.5m). When it is necessary to turn, two 45-elbow combinations should be used to replace the 90-right-angle elbow to reduce eddy current resistance. Bridge bends need to be set at the intersection of the pipeline to ensure smooth drainage.

Key Technology of Node Anti-blocking Structure

The connection between the drainage branch pipe and the riser should be a 45-oblique tee or a smooth water tee. The position where the branch pipe is connected to the riser should be not less than 1.5 times the horizontal distance from the bottom of the The drain of sanitary utensils should be set with a trap, and the depth of the water seal should not be less than 50mm to prevent the odor from returning in the pipeline. During the installation process, the open pipeline should be temporarily blocked, and special pipe plugging or plastic film should be used to wrap it to avoid cement mortar and construction waste from entering the lumen. The selection of floor drains should be preferentially anti-backflow type, the drain should be set with a filter screen, and the bathroom floor drain should be surrounded by a 0.5% slope slope to prevent the backflow of water in the ground area.

Sealing Performance Guarantee Construction Process

Pipe interface sealing is the core of the concealed application project. Before the socket connection, cotton yarn should be used to clean the inside of the pipe and pipe fitting socket to ensure that there is no oil and moisture. When applying the adhesive, the socket should be applied first and then the socket. The thickness is uniform. The amount of adhesive used in summer construction should be increased by 10%. After applying, the socket should be completed within 30 seconds. The insertion depth reaches the pipe fitting marking line. Rotate 1/4 turn to distribute the rubber layer evenly, and keep the interface standing and curing time not less than 30 minutes. Waterproof casing should be set at the floor of the riser. The casing is 50mm higher than the ground. The gap is filled with expansion fireproof sealant, and a 20mm high concrete water barrier ring is made around the pipe root.

Fixed bracket and stress testing specification

The fixed spacing of the pipeline must comply with the specification: the fixed spacing of the diameter of the riser DN50 is not more than 1.5m, and the diameter of the DN110 is not more than 2m; the fixed spacing of the horizontal pipe DN50 is not more than 0.5m, and the DN75 is not more than 0.75m. The bracket is fixed with a U-shaped card or a pipe card, and a rubber pad is added between the bracket and the pipeline to avoid condensation of the cold bridge. After the installation of the system is completed, a water passage test is carried out, all drains are opened, and the water is continuously passed for 15 minutes. Check that the pipeline interface is free of leakage and the drainage is smooth. Before concealment, a water closure test is required. Fill the pipeline with water for 24 hours, and the water level drop of no more than 5mm is qualified.

Post-maintenance and acceptance points

Before concealing the pipeline, video data should be taken and archived, and the pipeline direction and interface position should be marked. When completing the acceptance, key parameters such as drainage slope, bracket spacing, and water seal depth of the trap should be checked. Use a pipeline endoscope to check whether there is any foreign body blockage in the After delivery, the user should be provided with a drainage system maintenance manual, prompting regular dredging of the floor drain filter to avoid dumping hair, food waste and other sundries. In the low temperature environment in winter, it is necessary to ensure that the water trap seal does not freeze, and regular water can be replenished or antifreeze can be added.

PVC drain pipe indoor dark application construction needs to adhere to the principle of "anti-blocking priority, sealing-oriented", through scientific design, fine construction and strict acceptance, to build a safe and reliable drainage system. Construction units should strengthen technical disclosure, focus on controlling key processes such as slope setting and interface treatment, and combine BIM technology to comprehensively optimize pipelines to avoid conflicts with water supply and electrical pipelines, fundamentally eliminate the hidden danger of clogging and leakage, and ensure the safety of building functions and structures.