Engine valves

Gas and diesel engines

SOMAS valves have been used to control exhaust flow after combustion for many decades. This is true for both on and off-shore applications that utilize large engines. Current requirements on fuel efficiency have increased the need for precise control and complete shutdown of flow.
Typical exhaust applications today are: 
• Waste gate
• Cylinder bypass
• Systems used for reducing the amount of NOx
• Other systems where the heat produced by the exhaust fumes generates electricity
• Turbine closing and control
• Slow steaming

Somas engine valves

SOMAS butterfly valve is the most suitable for handling exhaust fumes. SOMAS unique valve shaft and flexible metal-seat results in very efficient control of the exhausts. The valves must be able to handle difficult temperature cycles, soot and corrosive substances in the exhaust-flow as well as strong vibrations. In order to minimize downtime for maintenance the design of bearing-casings and axis-seals are also important aspects for exhaust-installations.

SOMAS valves are designed with an extended shaft so it is possible to mount the actuator further away from the valve. The actuator and its accessories are more sensitive to heat in comparison to a valve. Therefore, it is important to move these specific parts as far away from the hot valve as possible.

The actuators can be set in a “fail-safe-mode”, pneumatic actuators with case-specific accessories are most commonly used to achieve the desired functionality. Electronic actuators can also be used, although this is much less common.

product information

SOMAS butterfly valves offer a number of functions that are specially designed for engine valves.

  • Dimensions for butterfly valves: DN80-DN1200, or up to DN1600 (upon request).
  • Dimensions for ball segment valves: DN25-DN65.
  • Pressure classes: PN10-PN50.
  • Butterfly valves with metal seats and ball segment valves with HiCo-seats perform good tightness and preform in accordance with current industry and application requirements.
  • Backlash free connection between valve and actuator and between actuator and positioner.  
  • Service-friendly design where the seat in both butterfly- and ball segment valves can be replaced without the need to remove the actuator. Furthermore, the valves do not need to be completely disassembled to be repaired.
  • Standard valves can handle temperatures up to 550 degrees Celsius.
  • High-temp. valves can handle up to 700 degrees Celsius.


SOMAS Application Handbook is an interactive tool where we have collected our many years of experience about valve options, material options as well as other important information about the valves we suggest for specific applications. The Application Handbook which is written in English can be ordered by contacting SOMAS. There is an option to download the book via the login zone. In order to download the Application Handbook, please contact us to receive your sign-in-credentials.

contact us

Are you interested in more information about SOMAS, our products or services? Please contact us by e-mail, phone or the form below.

Phone: +46(0)533-167 00