Cylindrical PTFE sealing plug valve, the valve body is equipped with a PTFE sleeve and the valve sleeve, which is pressed with a compression nut in the valve seat, the seal is sealed by the valve plug And Teflon sleeve asked a certain amount of interference to achieve, that is, the valve plug PTFE sleeve squeeze to achieve the seal. Therefore, the requirements of the valve plug and PTFE sleeve surface roughness value must be small, the geometric error must be small, in order to achieve the required pressure seal. If the seat sleeve needs to be compacted again in order to restore the sleeve seal, it must be yellow at the valve closing position to prevent the Teflon sleeve from being forced into the runner.