Control Valve is a valve used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. This enables the direct control of flow rate and the consequential control of process quantities such as pressure, temperature, and liquid level.


Popular Manufacturers:


Control Valve Manufacturers


  • Fisher
  • Masoneilan Camflex
  • Severn Glocon
  • RTK
  • Flowserve
  • Blakeborough
  • Orbit

  • Copes Vulcan
  • Siemens
  • Blakeborough
  • Saunders
  • Valtek
  • Kent Introl
  • Spirax Sarco

  • Honeywell
  • Bestobell Mobrey
  • Samson
  • Northvale Korting
  • Severn Unival
  • Johnson Controls
  • ARI Armaturen

  • Bossmatic
  • Baumann
  • Arca
  • Gestra
  • Winn



Leak Rates for Valves


All valves are designed to meet a designated internal permissible leak rate standard (FCI/ANSI).  There are six (6) permissible leak rates or Classes numbered 1 through VI. The higher the leak rate number, the lower permissible internal leak rate.

  • Class I valves will have the highest internal leak rate and usually the lowest cost.
  • Class VI valves will have the lowest permissible internal leak rate therefore cost will increase.

Identifying the permissible internal leak rate for a valve has to be one of the top priorities when choosing the correct valve.  A valve with a high leak rate, will cause excessive wear. The valves with a high leak rate will internally pass more medium and result in premature valve failure.

There are six different seat leakage classifications as defined by ANSI FCI 70-2.

  • Class I: is also known as dust tight and can refer to metal or resilient seated valves.
  • Class IV: is also known as metal to metal. It is the kind of leakage rate you can expect from a valve with a metal shut-off disc and metal seat.
  • Class Vl: is known as a soft seat classification. Soft Seat Valves are those where the seat or shut-off disc or both are made from some kind of resilient material such as Teflon.