Cryogenic Cam Butterfly Valve

The Cryogenic Cam Butterfly Valvenbsp;(CCV) is an innovative valve that can effectively operate across a wide range of temperatures, seal better than valves currently available on the market at those temperatures and can easily meet the demanding material requirements of a liquid oxygen (LOX) system. nbsp;The CCV was designed to replace obsolete Royal/Hadley valves, which have been used at NASArsquo;s Stennis Space Center (SSC) since the 1960rsquo;s as isolating valves in cryogenic fluid systems at SSC and have become costly to repair. nbsp;The CCV is innovative because it is the only butterfly valve that it can adapt to dynamic changes due to changing temperatures. nbsp;Temperature changes cause materials to expand and contract. nbsp;For example, a 12rdquo; long aluminum rod chilling down in liquid hydrogen (LH2) from room temperature to -423 degrees F will shorten the rod length by approximately 1/16rdquo;. nbsp;This may seem like an insignificant change, but it can cause a significant leak if the critical dimension between the valve disc and seat change. nbsp;Ideally, cryogenic valves should be able to compensate for these dynamic temperature changes and maintain a tight seal, but the different valves that were procured to replace the existing Royal/Hadley butterfly valves have not been successful passing the rigorous SSC cryogenic tests and material requirements for LOX systems. nbsp;It is this inability of existing butterfly valves to reliably perform as needed which triggered the innovative design of the CCV. nbsp;The CCV can seal better than other butterfly valves on the market because of the dual movement possible in the hybrid design. nbsp;To improve the sealing performance, the CCV combines the rotational movement of a butterfly with the translational movement of a globe valve.