Seal arrangement for a centrifugal type of pump

In a centrifugal type of gas compressing pump including impeller means located within a pump housing and connected to a power driven shaft assembly extending through a cooperating opening in said housing from outside thereof so as to rotate with said shaft assembly about the axis of the latter relative to said housing, whereby to cause gas within said housing to be centrifugally forced radially outward and thereby compressed within the housing, the improvement comprising a sealing arrangement for preventing said gas within said housing from escaping from the housing through said opening, said arrangement including an axial section of said shaft assembly and a fixed assembly extending circumferentially around and spaced from said axial shaft section, said shaft section and fixed assembly defining therebetween an axially extending, radially inwardly directed generally U-shaped passageway which serves as part of said cooperating opening between the interior of said pump housing, whereby the gas within said housing is able to pass into said passageway, said seal providing means also including means for sealing said passageway with liquid which is maintained within said passageway in a axially non-flowing state so as to prevent the gas within said housing from passing therethrough, whereby said liquid serves as an axially static liquid seal within said housing opening between said housing and rotating shaft during operation of said pump, some gas from within said housing passing into said passageway during the initial operation of the pump and said means for filling said passageway with liquid including means for condensing the gas that enters the passageway into liquid so as to fill said passageway sufficient to provide said liquid seal.

A pump apparatus for pressurizing a given fluid, comprising:

• (a) a pump housing defining an internal fluid compression chamber and inlet and outlet means into and out of said chamber for accommodating the passage of said fluid through the chamber from said inlet means to said outlet means;
• (b) means for pressurizing said fluid within said compression means including impeller means within said chamber, a shaft assembly having one end thereof connected with said impeller means within said chamber and extending out of said housing through a cooperating passageway separate from said inlet and outlet means, and means located outside said housing for rotating said shaft assembly and said impeller means about the axis of the shaft assembly, whereby to cause fluid within said housing to be pressurized;
• and
• (c) sealing means for preventing said fluid within said compression chamber from escaping said chamber through said passageway, said sealing means including means for maintaining liquid in an axially non-flowing static state entirely around an axial section of said shaft assembly and entirely filling an axial section of said passageway whereby said liquid seals said passageway against the passage of said fluid from within said housing;
• said fluid within said housing being steam and said liquid seal being water and said seal providing means including means for condensing some of said steam to use as said water seal.

In a centrifugal type of gas compressing pump including impeller means located within a pump housing and connected to a power driven shaft assembly extending through a cooperating opening in said housing from outside thereof so as to rotate with said shaft assembly about the axis of the latter relative to said housing, whereby to cause gas within said housing to be centrifugally forced radially outward and thereby compressed within the housing, the improvement comprising a sealing arrangement for preventing said gas within said housing from escaping from the housing through said opening, said arrangement including an axial section of said shaft assembly and a fixed assembly extending circumferentially around and spaced from said axial shaft section, said shaft section and fixed assembly defining therebetween an axially extending, radially inwardly directed generally U-shaped passageway which serves as part of said cooperating opening between the interior of said pump housing, whereby the gas within said housing is able to pass into said passageway, said seal providing means also including means for sealing said passageway with liquid which is maintained within said passageway in a nonaxially-flowing state so as to prevent the gas within said housing from passing therethrough, whereby said liquid serves as an axially static liquid seal within said housing opening between said housing and rotating shaft during operation of said pump, some gas from within said housing passing into said passageway during the initial operation of the pump and wherein said means for filling said passageway with liquid includes means for condensing the gas that enters the passageway into liquid so as to fill said passageway sufficient to provide said liquid seal, said condensing means includes a cooling plate forming part of said fixed assembly and means for maintaining said cooling plate sufficiently cold to condense said gas that enters said passageway.

In a pump including impeller or other such means located within a pump housing and connected to a power driven shaft assembly extending through a generally axially extending cooperating opening in said housing from outside thereof so as to rotate with said shaft assembly about the axis of the latter relative to said housing, whereby to cause fluid within said housing to be pressurized, the improving comprising a sealing arrangement for preventing said fluid within said housing from escaping from said housing through said opening, said arrangement including means forming part of said shaft assembly and part of said housing for providing an axially static continuous liquid seal extending circumferentially around an axial section of said shaft assembly within said opening and radially between said axial shaft section and said housing during operation of the pump whereby to seal said opening against the passage of said fluid from within said housing said seal displaying a fixed configuration depending on the difference in pressure between configuration depending on the difference in pressure between the interior and exterior of said housing, said seal providing means including a source of liquid located outside said housing for use as said seal and means for continuously introducing liquid from said source into said opening between said shaft section and said housing during operation of the pump so as to maintain fixed said configuration of said seal so long as the difference in pressure between the interior and exterior of said housing remains constant.

In a method of operating a centrifugal type of pump including impeller means located within a pump housing and connected to a power driven shaft assembly extending through a cooperating generally axially extending opening in said housing from outside thereof so as to rotate with said shaft assembly about the axis of the latter relative to said housing, whereby to cause fluid within said housing to be centrifugally forced radially outward, the improvement comprising the step of providing said axially extending opening with a generally u-shaped segment having radially extending legs along its length and preventing said fluid within said housing from escaping from said housing through said opening by providing a continuous axially static liquid seal extending circumferentially around an axial section of said shaft assembly within the u-shaped segment of said opening radially between said axial shaft section and said housing during operation of the pump, whereby to seal said opening against the passage of said fluid within said housing, said method including the steps of providing a source of liquid located outside said housing for use as said seal and introducing liquid from said source into said the u-shaped segment of opening between said shaft section and said housing during operation of said pump, so as to maintain constant the radial depth of said seal within the radial legs of the u-shaped segment so long as the difference in pressure between the interior and exterior of said housing is constant.

In an apparatus including a housing defining a chamber in which fluid and a rotating means within said chamber cooperate with one another such that the fluid therein is at a different pressure that the pressure outside the chamber, said apparatus also including a shaft assembly connected at one end to said rotating means for rotation therewith, said shaft assembly extending through a cooperating passageway in said housing so that its opposite end is located in an area which is outside said chamber and which is at a different pressure than said chamber, said passageway including a u-shaped segment having radially extending legs, the improvement comprising a sealing arrangement for preventing said fluid within said housing chamber from escaping from said chamber through said passageway, said arrangement including means forming part of said shaft assembly and part of said housing for providing a continuous axially static liquid seal which has a u-shaped configuration with radially extending legs and which extends circumferentially around an axial section of said shaft assembly within said passageway and radially between said axial shaft section and said housing during operation of the pump whereby to seal said passageway against the passage of fluid from within said housing, said seal providing means including source of liquid located outside said housing for use as said seal and means for continuously introducing liquid from said source into said opening between said shaft section and said housing during operation of the pump so as to maintain constant the radial depth of said seal within the radially extending legs of its u-shaped configuration so long as the difference in pressure within and outside said housing chamber is constant.