Hydrostatic seal for centrifugal pumps

Claim 2

A hydrostatic seal for high-differential pressure situations, comprises: an annular retainer plate having forward and aft ends for mounting said seal; an annular seal housing axially and detachably mounted to the forward end of said retainer plate; a floating seal sleeve, coaxially located along the interior wall of said seal housing; an outer pressure gap interposed between said seal housing and said floating seal sleeve for pressure balancing said floating seal sleeve; an annular seal sleeve coaxially located along the interior wall of said floating seal sleeve for mating with a rotating shaft; a purge fluid gap interposed between said floating seal sleeve and said seal sleeve; and means for pressurizing said seal.

Claim 3

The hydrostatic seal of claim 1 wherein said seal housing comprises: means for conveying a fluid through said seal housing; means for preventing rotation of said floating seal sleeve; and an annular aft end pressure restoration pocket located along the aft interior wall of said seal housing.

Claim 4

The hydrostatic seal of claim 2 wherein said means for conveying a purge fluid comprises at least one purge fluid feed hole radially located through said seal housing.

Claim 5

The hydrostatic seal of claim 3 wherein there is a plurality of purge fluid feed holes.

Claim 6

The hydrostatic seal of claim 2 wherein said means for preventing rotation comprises at least one anti-rotation lug.

Claim 7

The hydrostatic seal of claim 5 wherein there is a plurality of anti-rotation lugs.

Claim 8

The hydrostatic seal of claim 1 wherein said floating seal sleeve comprises: means for transferring a purge fluid to the inner periphery of said floating seal sleeve; means for preventing rotation of said floating seal sleeve; at least one inner pressure restoration pocket circumferentially located along the interior wall of said floating seal sleeve; and a pair of forward and aft axial seal balance lands circumferentially located along the forward and aft faces of said floating seal sleeve.

Claim 9

The hydrostatic seal of claim 7 wherein said means for transferring a purge fluid to the interior of said floating seal comprises at least one purge fluid transfer hole.

Claim 10

The hydrostatic seal of claim 8 wherein there is a plurality of purge fluid transfer holes.

Claim 11

The hydrostatic seal of claim 7 wherein said means for preventing rotation of said floating seal sleeve comprises an anti-rotation lug for each anti-rotation lug circumferentially located along the inner wall of seal housing.

Claim 12

The hydrostatic seal of claim 7 wherein there is a plurality of pressure restoration pockets.

Claim 13

The hydrostatic seal of claim 1 wherein said seal further comprises: a shaft sleeve interposed between said seal sleeve and a rotating shaft, and wherein said shaft sleeve becomes an integral part of the rotating shaft.

Claim 14

A hydrostatic seal for high-differential pressure situation, comprises: an annular retainer plate having forward and aft ends for mounting said seal; an annular seal housing axially and detachably mounted to the forward end of said retainer plate and wherein said seal housing comprises: a plurality of purge fluid feed holes radially located through said seal housing, for introducing a purge fluid into said seal; a plurality of anti-rotation lugs circumferentially located along the inner wall of said seal housing; and an annular aft end pressure restoration pocket located along the aft interior wall of said seal housing; a floating seal sleeve, coaxially located along the interior wall of said seal housing, and wherein said floating seal sleeve comprises: a plurality of purge fluid transfer holes radially located through said floating seal sleeve; an anti-rotation lug circumferentially located along the outer wall of said floating seal sleeve, for mating with each anti-rotation lug of said seal housing; a plurality of inner pressure restoration pockets circumferentially located along the interior wall of said floating seal sleeve; and a pair of forward and aft axial seal balance lands circumferentially located along forward and aft faces of said floating seal sleeve; an outer pressure gap interposed between said seal housing and said floating seal for pressure balancing said floating seal; an annular seal sleeve coaxially located along the interior wall of said floating seal sleeve for mating with a rotating shaft; a purge fluid gap interposed between said floating seal sleeve and said seal sleeve; and a shaft sleeve interposed between said seal sleeve and a rotating shaft.

Claim 15

A hydrostatic seal for high-differential pressure situation, comprises: an annular retainer plate having forward and aft ends for mounting said seal; an annular seal housing axially and detachably mounted to the forward end of said retainer plate and wherein said seal housing comprises: a plurality of purge fluid feed holes radially located through said seal housing, for introducing a purge fluid into said seal; a plurality of anti-rotation lugs circumferentially located along the inner wall of said seal housing; and an annular aft end pressure restoration pocket located along the aft interior wall of said seal housing; a floating seal sleeve, coaxially located along the interior wall of said seal housing, and wherein said floating seal sleeve comprises: a plurality of purge fluid transfer holes radially located through said floating seal sleeve; an anti-rotation lug circumferentially located along the outer wall of said floating seal sleeve, for mating with each anti-rotation lug of said seal housing; a plurality of inner pressure restoration pockets circumferentially located along the interior wall of said floating seal sleeve; and a pair of forward and aft axial seal balance lands circumferentially located along forward and aft faces of said floating seal sleeve; an outer pressure gap interposed between said seal housing and said floating seal for pressure balancing said floating seal; an annular seal sleeve coaxially located along the interior wall of said floating seal sleeve for mating with a rotating shaft; a purge fluid gap interposed between said floating seal sleeve and said seal sleeve; and a shaft sleeve interposed between said seal sleeve and a rotating shaft.

Claim 16

An interstage seal for high-differential pressure situations, comprises: an annular seal housing for containing a seal, wherein said seal housing comprises: at least one purge fluid feed hole radially located through said seal housing, for introducing a purge fluid into said seal; at least one anti-rotation pin circumferentially located along the inner wall of said seal housing; a floating seal sleeve, coaxially located along the interior wall of said seal housing, and wherein said floating seal sleeve comprises: at least one purge fluid transfer hole radially located through said floating seal sleeve; an anti-rotation pin circumferentially located along the outer wall of said floating seal sleeve, for mating with each anti-rotation pin of said seal housing; at least one pressure restoration pocket circumferentially located along the interior wall of said floating seal sleeve; and a pair of forward and aft axial seal balance lands circumferentially located along forward and aft faces of said floating seal sleeve; an outer pressure gap interposed between said seal housing and said floating seal sleeve for pressure balancing said floating seal sleeve; a purge fluid gap interposed between said floating seal sleeve and a pump shaft; and an annular retainer ring interconnected with the aft end of said seal housing for enclosing said seal.

Claim 17

An interstage seal for high-differential pressure situations, comprises: an annular seal housing for containing a seal, wherein said seal housing comprises: at least one purge fluid feed hole radially located through said seal housing, for introducing a purge fluid into said seal; at least one anti-rotation pin circumferentially located along the inner wall of said seal housing; a floating seal sleeve, coaxially located along the interior wall of said seal housing, and wherein said floating seal sleeve comprises: at least one purge fluid transfer hole radially located through said floating seal sleeve; an anti-rotation pin circumferentially located along the outer wall of said floating seal sleeve, for mating with each anti-rotation pin of said seal housing; at least one pressure restoration pocket circumferentially located along the interior wall of said floating seal sleeve; and a pair of forward and aft axial seal balance lands circumferentially located along forward and aft faces of said floating seal sleeve; an outer pressure gap interposed between said seal housing and said floating seal sleeve for pressure balancing said floating seal sleeve; a purge fluid gap interposed between said floating seal sleeve and a pump shaft; and an annular retainer ring interconnected with the aft end of said seal housing for enclosing said seal.

Claim 18

The interstage seal of claim 14 wherein there is a plurality of purge fluid feed holes.

Claim 19

The interstage seal of claim 14 wherein there is a plurality of anti-rotation pins.

Claim 20

The interstage seal of claim 14 wherein there is a plurality of purge fluid transfer holes.

Claim 21

The interstage of claim 14 wherein there is a plurality of pressure restoration pockets.