Multistage pump and manufacturing method

Claim 2

An improved multistage centrifugal pump manufacture comprising: a. a divided forged and formed pump housing having a generally round and elongated pumping chamber defined within said housing; b. a pump impeller assembly having a plurality of impellers serially mounted in interference fitted relation on a rotatable shaft and mounted with said housing within said chamber; c. a plurality of interstage pump volute members comprising jointed segments, said volute members fitted around said impeller assembly and between said impellers and removably mounted in said housing and disposed within said chamber, said volute members constructed and arranged for complete separation from said housing and said impeller assembly, while retaining said impellers mounted on the shaft, upon disjointure of said segments from one another and their movement transversely of said impeller assembly and away from their locations between said impellers to positions clear of the outer periphery of said impeller assembly, wherein retainer covers are mounted within said housing and about the ends of said Shaft for enclosing said chamber, and wherein seals are mounted in said retainer covers and about said shaft and means to provide an equal fluid pressure differential across said seals.

Claim 3

The manufacture of claim 1 wherein means incorporating said housing, said impeller assembly and said volute members cooperate to balance said shaft against longitudinal thrust from fluid pressure.

Claim 4

An improved multistage centrifugal pump comprising: a divided pump housing having a generally round and elongated pumping chamber defined within said housing, said housing including a lower case and an upper case, releasable fastener means for releasably retaining said upper and lower cases in assembled relation, a rotatably mounted pump impeller assembly having a rotatable shaft and a plurality of impellers serially mounted on said shaft and disposed within said chamber, a plurality of ring-shaped interstage pump volute members disposed around said shaft and between said impellers, means for releasably mounting said pump volute members within said chamber and on said upper and lower cases, each of said interstage pump volute members comprising complementary segments, and second releasable fastener means for releasably joining said complementary segments in assembled relation, wherein said means for mounting said pump volute members within said chamber and on said upper and lower cases comprise circumferential radial flanges on said complementary segments and cooperating groove means in said upper and lower cases for receiving said flanges, and detent means on each of said volute members and complementary detent means on at least one of said cases for preventing rotation of said volute members in said cases.

Claim 5

An improved multistage centrifugal pump comprising: a divided pump housing having a generally round and elongated pumping chamber defined within said housing, said housing including a lower case and an upper case, releasable fastener means for releasably retaining said upper and lower cases in assembled relation, a rotatably mounted pump impeller assembly having a rotatable shaft and a plurality of impellers serially mounted on said shaft and disposed within said chamber, a plurality of ring-shaped interstage pump volute members disposed around said shaft and between said impellers, means for releasably mounting said pump volute members within said chamber and on said upper and lower cases, each of said interstage pump volute members comprising complementary segments, and second releasable fastener means for releasably joining said complementary segments in assembled relation, wherein said means for mounting said pump volute members within said chamber and on said upper and lower cases comprise circumferential radial flanges on said complementary segments and cooperating groove means in said upper and lower cases for receiving said flanges, and detent means on each of said volute members and complementary detent means on at least one of said cases for preventing rotation of said volute members in said cases.

Claim 6

An improved multistage centrifugal pump comprising: a divided pump housing having a generally round and elongated pumping chamber defined within said housing, said housing including a lower case and an upper case, releasable fastener means for releasably retaining said upper and lower cases in assembled relation, a rotatably mounted pump impeller assembly having a rotatable shaft and a plurality of impellers serially mounted on said shaft and disposed within said chamber, a plurality of ring-shaped interstage pump volute members disposed around said shaft and between said impellers, means for releasably mounting said pump volute members within said chamber and on said upper and lower cases, each of said interstage pump volute members comprising complementary segments, and second releasable fastener means for releasably joining said complementary segments in assembled relation, wherein said housing further comprises retainer covers at the ends of said housing and about the ends of said rotatable shaft, shaft seals mounted in said retainer covers and about said rotatable shaft, and pressure equalizing means for equalizing the fluid pressure differential across said seals.

Claim 7

An improved multistage centrifugal pump comprising: a divided pump housing having a generally round and elongated pumping chamber defined within said housing, said housing including a lower case and an upper case, releasable fastener means for releasably retaining said upper and lower cases in assembled relation, a rotatably mounted pump impeller assembly having a rotatable shaft and a plurality of impellers serially mounted on said shaft and disposed within said chamber, a plurality of ring-shaped interstage pump volute members disposed around said shaft and between said impellers, means for releasably mounting said pump volute members within said chamber and on said upper and lower cases, each of said interstage pump volute members comprising complementary segments, and second releasable fastener means for releasably joining said complementary segments in assembled relation, wherein said housing further comprises retainer covers at the ends of said housing and about the ends of said rotatable shaft, shaft seals mounted in said retainer covers and about said rotatable shaft, and pressure equalizing means for equalizing the fluid pressure differential across said seals.

Claim 8

An improved multistage centrifugal pump as defined in claim 4, wherein said housing, said impeller assembly and said volute members cooperate to balance said shaft against longitudinal thrust from the fluid pressure.