According to the structural characteristics of the plug valve and the design can achieve the function, it is recommended to use the following principles: 1, for the distribution of media and change the direction of medium flow, Kai working temperature ≤ 300 ℃, nominal pressure ≤ 1.6MPa, nominal pass through ≤ 300mm, it is recommended to use multi-channel plug valve. 2, milk, fruit juice, beer and other food companies and pharmaceutical companies and other equipment and pipelines, it is recommended to use tight austenitic stainless steel cone stopcock valve. 3, oil field exploitation, natural gas field extraction, pipeline transportation branch, scouring and cleaning equipment, the nominal pressure level ≤ CL300, nominal pass through ≤ 300mm, working temperature ≤ 340 ℃, the proposed selection of oil-sealed conical plug valves. 4, oil field exploitation, natural gas field extraction, pipeline transportation branch, scouring and cleaning equipment, the nominal pressure level ≤ CL2500, nominal pass through ≤900mm, working temperature ≤340 ℃, the proposed selection of pressure balance inverted conical plug valve. 5, in large-scale chemical industry, corrosive media containing pipelines and equipment, requiring the opening or closing faster occasions, for nitric acid-based media, optional 1Cr18Ni9 stainless steel PTFE sleeve seal Conical plug valves; for acetate-based media, optional Cr18Ni12Mo2Ti stainless steel PTFE sleeve sealing conical plug valves. 6, in the gas, natural gas, HVAC piping and equipment, when the nominal pressure ≤ 1.0MPa, nominal pass through ≤ 200mm, should use filler-type conical plug valves.