There are mainly three types of connection methods for PVC pipes: sealing rubber ring, bonding and flange connection. Pipes with a pipe diameter greater than or equal to 100 mm generally use apron joints; pipes with a pipe diameter less than 100 mm generally use bonding discussion, and some accept live discussion. When the pipeline exceeds the sewers or other pipelines, metal pipes are usually used, and the plastic pipes and metal pipes are connected by flanges. The connection between the front and rear of the valve and the pipeline is also flanged. When the small-diameter pipe is bonded by solvent, the socket must be rounded to form a bevel, and ensure that the fracture is flat and the axis is vertical, so that the bonding can be firm and water leakage can be prevented. Generally, PVC pipes with a pipe diameter greater than or equal to 100 mm use apron joints. Before installation, personnel must chamfer the pipe socket, and check whether the quality of the rubber ring is qualified. The socket, rubber ring, etc. must be wiped clean during placement. The trench excavation for traditional pipeline placement only requires that the pipeline can be placed in the trench and can be sealed. When the original soil layer is not loosened, it is not necessary to pressurize and compact the cushion. Generally, the branch pipe of the PVC pipe can be split by a tee or a vertical water stop. During construction, a saddle-shaped fitting can be added with half a two-in-one tee, and it is clamped with U-shaped bolts, which thickens the pipe wall, and then drills directly on it to open the teeth, and then uses external threaded plastic parts to connect it out. Experiments show that with this method, the post-construction pressure test and acceptance can fully meet the requirements of the model. Other positions where the water flow in the pipe generates thrust, such as elbows, tees and pipe end sealing plates, should be provided with thrust piers to withstand the thrust of the water flow. As a new type of non-metallic pipe, PVC pipe can not be detected with the existing metal pipe detection configuration, but if the pipe is buried, a wire can be easily solved by burying a wire on the pipe during working hours.
