Patent US3801217A successfully refreshed from Google Patents.
US3801217A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid machines
Assignee: Weir Pumps Ltd
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Filing: 1972-01-11
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Granted: 1974-04-02
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Expires: 1992-01-11
Abstract
Abstract A multi-stage centrifugal pump which includes a plurality of stages the impellers of which are mounted on a shaft common to all stages. All the stages are mounted within a tie-frame carrying pump inlet and delivery connections and are arranged between an inlet end member and a delivery end member. The end members and the casings of each stage are arranged in abutting relationship so that they are urged in a direction towards the inlet member by the delivery pressure acting on a combination of a delivery end cover and the delivery end member, the inlet end member being held against movement relative to the tie-frame while the delivery end member is capable of movement relative to the tie-frame, sealing means being provided between the tie-frame and the movable member.
Inventors
- 👤 M Ryall
- 👤 H Anderson
- 👤 G Pezzani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:12
CPC Classifications
F; F04; F04D; F04D1/00; F04D1/06; F04D1/063
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
182 words
A multi-stage centrifugal pump including a plurality of stages each of which includes a casing and an impeller rotatable therein, the pump including a shaft having an impeller of each stage mounted thereon, a tie frame carrying pump inlet and delivery connections, and including means surrounding said casings to define an annular passage therearound whereby said casings are subjected to only suction pressure, fluid communication means to connect said annular passage with said pump inlet connection, an inlet end member and a delivery end member, said annular passage extending between said delivery end members and enclosed by said tie frame so that during operation the delivery end member and said plural stage casings as interposed between said inlet and delivery end members are urged together in a direction towards the inlet end member by the delivery pressure acting on the delivery end member, holding means being provided to hold the inlet end member against movement relative to the tie frame in said direction, and seal means being provided between the delivery end member and the tie frame to permit relative movement therebetween.
Claim 2
Dependent Claim
182 words
A multi-stage centrifugal pump including a plurality of stages each of which includes a casing and an impeller rotatable therein, the pump including a shaft having an impeller of each stage mounted thereon, a tie frame carrying pump inlet and delivery connections, and including means surrounding said casings to define an annular passage therearound whereby said casings are subjected to only suction pressure, fluid communication means to connect said annular passage with said pump inlet connection, an inlet end member and a delivery end member, said annular passage extending between said delivery end members and enclosed by said tie frame so that during operation the delivery end member and said plural stage casings as interposed between said inlet and delivery end members are urged together in a direction towards the inlet end member by the delivery pressure acting on the delivery end member, holding means being provided to hold the inlet end member against movement relative to the tie frame in said direction, and seal means being provided between the delivery end member and the tie frame to permit relative movement therebetween.
Claim 3
Dependent Claim
24 words
A pump as claimed in claim 1, wherein said seal means between the delivery end member and the tie frame comprises a sliding packing.
Claim 4
Dependent Claim
35 words
A pump as claimed in claim 1, further including additional seal means in the form of a piston ring being provided downstream of said seal means between the delivery end member and the tie frame.
Claim 5
Dependent Claim
30 words
A pump as claimed in claim 3, further including a pressure gauge provided between said seal means and said piston ring to detect leakage of fluid past said seal means.
Claim 6
Dependent Claim
41 words
A pump as claimed in claim 1 further including a resilient member interposed between the highest pressure stage and the delivery end member, said resilient member tending to force the highest pressure stage and delivery end member away from each other.
Claim 7
Dependent Claim
34 words
A pump as claimed in claim 5, wherein said resilient member is an annular plate and wherein the elasticity of the metal of the plate urges the plate to or from a conical shape.
Claim 8
Dependent Claim
64 words
A pump as claimed in claim 1, wherein said impellers, said casings, said inlet end member, said delivery end member and one end cover member are assembled around said shaft as a unitary assembly, fixing means being provided to removably connect said end cover member with said barrel such that on removal of said fixing means said unitary assembly is removable from the barrel.
References Cited (Backward Citations)
FR398640A
Cited
GB168058A
Cited
US1837873A
Cited
US2108786A
Cited
GB526732A
Cited
GB645921A
Cited
US2843048A
Cited
GB838317A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |