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1. The socket type is that a tube is inserted into another tube, and then fixed with cement or glue. The socket tube is at the connection point, and generally the rubber ring is needed to seal the connection point. Groove handling under the socket pipe is relatively simple

2. The tongue-and-groove type is that two water pipes are connected in parallel and the sealing ring is placed in the middle to fix it with a silk. The tongue and mouth pipe is generally connected at the connection point by a wiper. The treatment of the groove under the tongue and groove pipe requires the laying of a concrete cushion.