EP0481598A2
Expired / Lapsed
EP
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Centrifugal pump with sealing means
Assignee: Sulzer Pumpen AG
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Filing: 1991-09-04
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Granted: —
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Expires: 2011-09-04
Abstract
Abstract A centrifugal pump for pumping fiber suspensions includes a centrifugal pumping housing (50) having an inlet (52) and an outlet for the suspension and a centrifugal impeller within the centrifugal pump housing. A vacuum pump (70) is placed adjacent the centrifugal pump housing (50) and includes a vacuum pump chamber defined by first and second opposed side walls (110, 112) and a vacuum pump rotor which is eccentrically mounted within the vacuum pump chamber. The rotor has radially extending opposed side edges facing the vacuum pump side walls (110, 112) forming a clearance therebetween. The pump includes a conduit within at least one of the vacuum pump side walls (110, 112) for supplying a sealing liquid to the clearance (122) between the rotor and at least one of the side walls of the vacuum pump chamber (76). Flushing liquid may be supplied through the same sealing liquid conduits or separately therefrom. The centrifugal pump may include a fluidizing impeller.
Inventors
- 👤 Harold Haavik
- 👤 Tapio Peroaho
- 👤 Reijo Vesala
- 👤 Vesa Vikman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 04:28
CPC Classifications
F; F04; F04C; F04C19/00; F04C27/00; F04C27/02; F04D; F04D7/00; F04D7/02; F04D7/04; F04D7/045; F04C2220/00; F04C2220/20; F05; F05B; F05B2210/00; F05B2210/10; F05B2210/13; F05B2210/132
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
172 words
A centrifugal pump for pumping a gas-containing medium said pump including: a centrifugal pumping housing (50) having an inlet (52) and an outlet for said medium; a centrifugal impeller (60) within said centrifugal pumping housing (50): a liquid ring vacuum pump (70) adjacent said centrifugal pumping housing (50), said vacuum pump including a vacuum pump chamber (76) defined by first and second opposed side walls (112, 110) spaced apart by a circumferential annular wall (100); a vacuum pump rotor eccentrically positioned within said vacuum pump chamber (76), said rotor having outwardly extending opposed side edges facing said vacuum pump side walls (112, 110) and forming a clearance therebetween; a rotary shaft (58) extending through said vacuum pump chamber and into said centrifugal pump housing (50); said centrifugal pump impeller and said vacuum pump rotor being mounted on said shaft in spaced relation to each other; chacacterized in means for sealing said clearance (122) between said rotor and at least one of said side walls (112, 110) of said vacuum pump chamber (76).
Claim 2
Dependent Claim
62 words
The centrifugal pump as claimed in claim 1, characterized in that said means in a sealing liquid and that there is means within at least the vacuum pump side walls (112) closer to the centrifugal impeller (60) for supplying a sealing liquid to said clearance (122) between said rotor and at least said side wall (112) of said vacuum pump chamber (76).
Claim 3
Dependent Claim
26 words
The centrifugal pump as claimed in claim 2, characterized in that said sealing liquid supply means is located between said shaft (58) and said liquid ring.
Claim 4
Dependent Claim
82 words
The centrifugal pump as claimed in claim 2, characterized in that said rotor (96) comprises a central portion (102) circumjacent said shaft (58) having opposite ends adjacent said side walls (110, 112); and said means for supplying a sealing liquid comprises at least one conduit (118, 120) leading to said vacuum pump chamber (76) and communicating with said clearance (122) between at least one of said opposite end of the rotor central portion (102) and said vacuum pump side wall (110, 112).
Claim 5
Dependent Claim
67 words
The centrifugal pump as claimed in claim 2, characterized in an intermediate wall (72, 112) separating said centrifugal impeller (60) from said vacuum pump impeller (96) and said means for supplying said sealing liquid comprises a first sealing liquid conduit (118) extending through said side wall (110) and a second sealing liquid conduit (120) extending through said intermediate wall (72, 112) to said vacuum pump chamber (76).
Claim 6
Dependent Claim
118 words
The centrifugal pump as claimed in claim 4, characterized in that said means for supplying said sealing liquid comprises a single sealing liquid inlet port (124) and a conduit (126, 127) connected to said inlet port (124); said vacuum pump rotor (96) comprising two lateral ends, and at least one throughbore (130) through said central portion and in communication with said clearance (122) between said rotor and said first and second opposed side walls (110, 112); said conduit (126) being in communication with at least one of said opposed side walls (110) and maid throughbore (130) for supplying sealing liquid to said clearance (122) between said rotor and both said second and first opposed side walls (110, 112).
Claim 7
Dependent Claim
47 words
The centrifugal pump as claimed in claim 6, characterized in that said central portion (102) of said vacuum pump rotor (96) comprises a first circular groove (128) extending along said one lateral end of said rotor, said first groove (128) communicating with said sealing liquid supplying means.
Claim 8
Dependent Claim
29 words
The centrifugal pump as claimed in claim 7, characterized in that said circular groove additionally communicates with said at least one throughbore (130) within said rotor central portion (102).
Claim 9
Dependent Claim
51 words
The centrifugal pump as claimed in claim 7, characterized in a second circular groove (132) extending along said other lateral end of said rotor and communicating with said at least one throughbore (130) within said rotor central portion (102) opposite said first circular groove (128) and facing said side wall (112).
Claim 10
Dependent Claim
42 words
The centrifugal pump as claimed in claim 4, characterized in that at least one of said side walls (110, 112) comprises a circular groove (128) facing said one end of said rotor, said groove (128) communicating with said seeling liquid supplying means.
Claim 11
Dependent Claim
37 words
The centrifugal pump as claimed in claim 6, characterized in a circular groove within at least one of said side walls and in communication with said at least one throughbore (130) within said rotor central portion (102).
Claim 12
Dependent Claim
50 words
The centrifugal pump as claimed in claim 11, characterized in a second circular groove (132) extending along said other side wall (112) facing said other end of said rotor and communicating with said at least one throughbore (130) within said rotor central portion (102) opposite said first circular groove (128).
Claim 13
Dependent Claim
25 words
The centrifugal pump as claimed in claim 2, characterized in means for supplying flushing liquid to said vacuum pump for removing said fiber suspension therefrom.
Claim 14
Dependent Claim
68 words
The centrifugal pump as claimed in claim 13, characterized in that said flushing liquid supply means comprises an intermediate wall (72) separating said centrifugal impeller (60) from said vacuum impeller (96), and a liquid inlet duct (86, 88) for feeding liquid to said vacuum pump (70), said liquid inlet duct (86) extending within said intermediate wall (72) and communicating with said chamber (76) of said vacuum pump (70).
Claim 15
Dependent Claim
33 words
The centrifugal pump as claimed in claim 2, characterized in a rotor with fluidizing blades (71) for fluidizing a fiber suspension mounted on said shaft (58) in front of said centrifugal impeller (60).
Claim 16
Dependent Claim
20 words
The centrifugal pump as claimed in claim 15, characterized in that said fluidizing rotor is extends outside said pump inlet.
Claim 17
Dependent Claim
76 words
The centrifugal pump as claimed in claim 2, characterized in that said vacuum pump chamber (76) has a pressure side and a suction side and additionally comprising a gas discharge opening (80) at said pressure side of said chamber (76); a gas inlet port (94) at said suction side communicating with said centrifugal pumping housing; and a make-up air inlet duct (84) in said rear wall of said chamber (76) opposite said air inlet port (94).
Claim 18
Dependent Claim
58 words
The centrifugal pump as claimed in claim 2, characterized in that said vacuum pump chamber (76) additionally comprises a gas outlet; said vacuum pump rotor including a rotor central portion (102) circumjacent said shaft (58) and vanes (98) extending substantially radially from said rotor central portion (102); said rotor central portion (102) being tapered toward said gas outlet.
Claim 19
Dependent Claim
40 words
The centrifugal pump as claimed in claim 1, characterized in that said means is a mechanical sealing (140, 142, 146) arranged at least on one of said side walls(112, 110) and the rotor surfaces facing said side walls (112, 110).
Claim 20
Dependent Claim
25 words
The centrifugal pump as claimed in claim 19, characterized in that said mechanical sealing (146) is annular and made of non-galling material such as Teflon.
Claim 21
Dependent Claim
34 words
The centrifugal pump as claimed in claim 19, characterized in that said mechanical sealing is formed of a pair of annular sealing rings (140, 142), of which one is stationary and the other rotating.
Claim 22
Dependent Claim
36 words
The centrifugal pump as claimed in claim 21, characterized in that at least one of said rings (140, 142) is resiliently mounted on one of said side wall (110, 112) and said rotor central portion (102).
Claim 23
Dependent Claim
35 words
The centrifugal pump as claimed in claim 20, characterized in that said annular ring (148) extends at the side wall (110, 112) substantially radially from the rotor central portion (102) to the rotor vaned portion.
References Cited (Backward Citations)
No citation records indexed.
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