TPI May 2013

valves , f i t t ings , f langes and connectors

Compact cryogenic valve with integrated pneumatic actuator

insulated pipes, including upside-down installation.

Cryogenic valves are typically space consuming, due to the large distance between the actuator and the medium. Conventional actuators lose power when they are exposed to temperatures below -40°C. Conventional cryogenic valves are therefore designed with long valve body and stem to position the actuator as far as possible from the cryogenic medium, to avoid freezing and condensation. Using the new FREES compact technology, Stöhr Armaturen has developed a very compact valve with an integrated actuator. The claimed advantages of the valve include pneumatic drive suitable for use in cryogenic applications (down to -196°C); maximum possible height reduction, total weight reduction, and smaller footprint of the actuator; and unrestricted fitting position in vacuum-

Stöhr Armaturen designs and manufactures valves for industrial gas, chemical and pharmaceutical industries, for applications in aerospace, marine engineering and energy engineering as well as in research institutes. Its standard product range consists of a variety of globe or control valves, check valves, pressure relief valves and filters in different body types with diameters up to DN250. Valve bodies are made from a single piece of stainless or special steel, and are sealed with bellows. A variety of connections and surface treatments are available, along with special designs for specific customer requirements in terms of temperature range, pressure range, life cycle extension or materials.

nectors

The 6-bar industry standard for the operating pressure of pneumatic valves is retained, and maintainability of the valve stem and actuator allows installation and removal of the actuator and valve insert unit without opening the vacuum system. Change of actuator can be performed without opening the media space, which means that no system downtime is required. In addition, life cycle of the pneumatic actuator is extended by replacing O-ring seals with bellows. For the prototype a number of different ideas were implemented, such as using the dead space for functional units, avoiding long valve stems, replacing stainless steel components with alternative materials, using stainless steel pneumatic cylinders of variable length, and separation of mounting and sealing forces. New features include the replacement of heat-transmitting stainless steel components by special cryogenic-grade plastics, including pressure and force transmitting parts in cryogenic areas such as the valve stem. In addition, minimised frictional forces and an overall low-wear design were achieved.

Stöhr Armaturen GmbH & Co KG – Germany

Stöhr compact valve with integrated actuator

info@stoehr-valves.de www.stoehr-valves.de

International Tube & Conduit Company Ltd.

• British Standard Conduits BS31 / BS4568 • Electrical Metallic Tubing EMT • Intermediate Metal Conduit IMC

• Rigid Metal Conduit

RMC

• Flexible Conduit

FC

• Fittings

T: +966 2 6060275 - F: +966 2 6061095 - P.O. Box 10374 Jeddah 21433 - KSA E-mail: sales@itcc-group.com - www.itcc-group.com

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Tube Products International May 2013

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