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Process diaphragm pumps / metering pumps need to have pulsation dampeners with PTFE double layer membrane and secondary containment seal. Chemical & Process metering pumps with PTFE diaphragm sandwich are hermetically sealed, and must be matched by the same safe features in the pulse-dampers design.
A diaphragm pump is a positive displacement pump that uses a combination of the reciprocating action of a rubber, thermoplastic or Teflon diaphragm and suitable non-return check valves to pump a fluid. Sometimes this type of pump is also called a membrane pump.
