Hydraulic Flow Restrictors, Controllers & Sealing Solutions

The fluid power sector incorporates fluid systems of mechanical engineering, mobile hydraulics, conveyor technology and mold construction. With over 40 years’ experience as world leaders in these areas, SFC KOENIG® has developed and engineered the world’s leading sealing, fluid and hydraulic flow control products. KOENIG EXPANDER®KOENIG RESTRICTOR® and KOENIG CHECK VALVE® components are proven reliable, providing dependable, leak-free sealing and precision flow control. Our quality sealing, fluid power and hydraulic flow restrictor components are designed for closing drilled holes in a broad variety of hydraulic applications such as hydraulic manifolds, pumps and motors, fuel injection systems, exhaust emission systems, gear housings, brake and steering systems to name a few. Our sealing, fluid power and hydraulic flow control solutions meet the highest quality standards, maintain all the required certification and promise the highest level of safety and reliability with part field failure rate averages of less than 1 PPM.

In fluid systems, hydraulic or gaseous media are moved through drilled holes or channels. These channels need to be sealed against pressure and be completely leak proof. Common sealing methods such as screws with rubber o-rings and sealing components, press-fitting of pins or welding up of drilled holes have high production costs and cannot be reliably reproduced. The KOENIG EXPANDER allows secure and quick sealing of drilled holes with little production effort and provides reliable safety even under extreme conditions. SFC KOENIG fluid power and hydraulic flow restrictor components are perfectly suitable for tamper proof flow control and regulation. Engineering and technical field support completes our dedicated service to our customers with the final outcome of considerable savings in time and money being made in their assembly processes.

SFC KOENIG hydraulic flow control technologies have been used in a variety of fluid power applications including:

  • brake systems
  • clutch systems
  • control valves
  • crank shafts
  • cylinder & cylinder heads
  • drive shafts
  • drivelines
  • engines & engine blocks
  • engine covers
  • exhaust emission systems
  • fuel injection systems
  • gear housings
  • hydraulic manifolds
  • oil pumps
  • pumps and motors
  • steering systems
  • transmissions & transmission shafts
  • water pumps


With over 5 billion parts installed world-wide, SFC KOENIG sealing and flow control components have proven effective in a variety of hydraulic applications. Our parts are proven dependable, with less than 1 PPM field failure rates, and can withstand the harsh environments and high pressures of sealing, fluid power and hydraulic flow control applications. SFC KOENIG components are available in a wide range of standard sizes and pressure ratings, and our engineers are ready to provide design-in process support for any hydraulic or fluid power application needs.

Fluid Power
SFC Koenig hydraulic flow restrictor


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