Purged valve assembly and method of sealing
AssigneeInternational Telephone and Telegraph Corporation
InventorWilliam G. Haesloop
Life of this patent
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Abstract
A purged valve assembly and method of sealing for a liquid transmitting casing that extends into a storage reservoir for liquid or liquified gases. The assembly includes a normally closed spring-biased foot valve mounted on the lower end of the casing. A pump and motor unit slidably mounted in the casing opens the foot valve when resting thereon. A purged double seal on the foot valve prevents any leakage of liquid or liquified gas inwardly through the valve into the interior of the casing when the pump and motor unit is lifted off the foot valve.
Claims12
A purged valve assembly for a fluid transmitting casing of a pumping system especially suited for a cryogenic fluid storage reservoir comprising:
- a cylindrical upright housing adapted to be fixed to the bottom of said casing;
- a foot valve element including a central portion extending upwardly into said housing and a radially extending foot plate means underlying the lower end of said housing;
- substantially concentric, spaced inner and outer annular sealing lips between the upper surface of said foot plate means and said lower end of said housing, said lips defining an annular space therebetween;
- means normally holding said foot valve element upwardly against said housing to cause said lips to provide a double seal between said foot plate means and said lower end of said housing;
- and
- a port in said housing extending from the bottom thereof between said lips to the exterior of said housing for allowing the introduction of purge gas into said annular space.
A purged valve assembly for a fluid transmitting casing of a pumping system especialy suited for a cryogenic fluid storage reservoir comprising:
- a cylindrical upright housing adapted to be fixed to the bottom of said casing;
- a foot valve element including a central portion and a radially extending foot plate means underlying the lower end of said housing;
- generally concentric, spaced inner and outer annular sealing lips between the upper surface of said foot plate means and said lower end of said housing, said lips defining an annular space therebetween;
- spring means biasing said foot valve element upwardly toward said housing to a closed position causing said lips to provide a double seal between said foot plate means and said lower end of said housing;
- and
- means providing flow communication to said annular space when said foot valve element is in said closed position to the introduction of purge gas into said annular space.
A method of providing a seal between a reservoir and the exterior environment to prevent leakage of gas from the reservoir to said environment, comprising the steps of:
- providing a casing in said reservoir extending from the top to a bottom portion of the reservoir, an opening at the upper end of said casing, valve means for closing the bottom of said casing, said valve means having a double concentric seal defining an annular space therebetween;
- and
- introducing a purging gas into said annular space while said valve means is closed to prevent leakage of gas from said tank through said casing.
A purged valve assembly for a fluid transmitting casing of a pumping system especially suited for a cryogenic fluid storage reservoir comprising:
- a cylindrical upright housing adapted to be fixed to the bottom of said casing;
- a foot valve element underlying the lower end of said housing;
- substantially concentric, spaced inner and outer annular sealing lips between the upper surface of said foot valve element and said lower end of said housing, said lips defining an annular space therebetween;
- means for shifting said foot valve element upwardly against said housing to cause said lips to provide a double seal between said foot valve element and said lower end of said housing;
- and
- a port communicating with said annular space for allowing the introduction of purge gas into said space.
Dependencies are inferred from the claim text.