Patent ID: 7472551

Claim:
A cryogenic process system comprising: an insulated housing; process equipment located within the insulated housing; a conduit located within the insulated housing for passing cryogenic fluid to the process equipment; and a filter assembly for filtering the cryogenic fluid passing within the conduit to the process equipment, said filter assembly having a filter housing connected to the conduit upstream of the process equipment so that the cryogenic fluid flows through the filter housing, the filter housing containing a filter element to filter the cryogenic fluid passing through the filter housing, a bonnet, at one end, connected to the filter housing and an access flange sealing the other end of the bonnet to permit access to the filter; said filter assembly positioned such that the bonnet extends through an opening of the insulated housing to outside of the insulated housing, the access flange is exposed to the ambient air and the filter housing is situated within the insulated housing, the filter assembly having no insulation such that a heat leakage exists from the outside of the insulated housing from the ambient air through the bonnet to the filter housing and the bonnet being at an angle with respect to the horizontal within the range of from 15 to 90 degrees so that the heat leakage causes a portion of the liquid in the filter housing to vaporize creating a gas trap preventing cryogenic fluid from vaporizing in the filter.