The difference between a flat gate valve with a diversion hole and a gate valve without a diversion hole has a diversion hole flat gate valve (Z43H), the medium will pass through the inner hole of the gate, and the flow channel with a diversion hole structure is always sealed whether it is fully open or fully closed. The surfaces are matched, and the sealing surface is protected from direct erosion by the medium, thereby prolonging the service life. If the medium has impurity particles, it will not touch the sealing surface. The more obvious function is to clean the pipe and protect the sealing surface. Therefore, there are more media that can be removed by the diversion flat gate valve. Non-diversion hole flat gate valve (Z43WF), the medium directly goes through the valve body. The flow channel without diversion hole is fully open, and the valve seat sealing ring will be directly washed by the medium without protection. If the medium has impurity particles, it is easy to damage the sealing surface. Therefore, the flat gate valve without diversion can only take clean media such as clean water, refined oil, and fuel. It is easy to be damaged if there are impurities in the hard seal. Flat gate valves with diversion holes can be used instead of flat gate valves without diversion holes, and flat gate valves without diversion holes cannot be used instead of flat gate valves with diversion holes. The correct selection of flat gate valves, flat gate valves with diversion holes are generally used in the medium with impurities, crude oil, natural gas, etc. The model number (Z43DF, Z43DH, Z43DY) D represents a diversion hole, generally abbreviation can be directly omitted, just write Z43 and then a sealing surface F, H, Y is with diversion. Flat gate valve without diversion hole is generally clear water , Gasoline, fuel oil, natural gas, etc. Model (Z43WF) W represents no diversion hole, more people mistakenly mix flat gate valve W with ordinary gate valve body directly processing hard seal W, and Z43WH thinks it is a direct valve body. Processing hard seal. The flow channel without diversion hole is fully open, and the valve seat sealing ring will be directly washed by the medium without protection. If the medium has impurity particles, it is easy to damage the sealing surface. Therefore, the flat gate valve without flow guide can only take clean medium, and it is easy to be damaged if the hard seal takes away the impurity medium.