SEALING ARRANGEMENT FOR A FLOW MACHINE
The present invention relates to a sealing arrangement for a flow machine. The sealing arrangement of the present invention is applicable for sealing bearing arrangements of centrifugal pumps, mixers, blowers etc. The present invention is especially applicable in sealing a bearing assembly including two angular contact ball bearings used in back-to-back configuration. The present invention relates especially to a baffle arranged between the bearing and the bearing housing, the baffle leaving a gap between itself and the inner bearing ring for the oil to flow from the bearing to the oil channel, and from the oil channel via a groove back to the oil chamber.
1 . A sealing arrangement for a flow machine, the flow machine comprising at least an axis, a shaft ( 4 ), a thrust bearing ( 6 ) formed of a pair of angular contact ball bearings in back-to-back configuration, the ball bearings having an inner bearing ring ( 6 i ) and an outer bearing ring ( 6 o ), a shaft sealing ( 8 ), a bearing cover ( 30 ) at an outer end of the flow machine, an oil chamber ( 22 ) at the side of the thrust bearing ( 6 ) opposite the bearing cover ( 30 ), a baffle ( 32 , 32 ′, 32 ″) arranged between the thrust bearing ( 6 ) and the bearing cover ( 30 ) for forming an oil channel ( 38 ) between itself and the bearing cover ( 30 ), and a return groove ( 20 ) or bore for returning oil from the oil channel ( 38 ) to the oil chamber ( 22 ), characterized in a gap ( 36 ) between the baffle ( 32 , 32 ′, 32 ″) and the inner bearing ring ( 6 i ) for the entire oil flow from the bearing to the oil channel ( 38 ) and further to the oil chamber ( 22 ).
2 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 , 32 ′) is positioned against the outer bearing ring ( 6 i ), the baffle ( 32 , 32 ′) extending radially inwardly to the side of the inner bearing ring ( 6 i ) leaving the gap ( 36 ) therebetween.
3 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 , 32 ′, 32 ″) has an inner circumference or surface ( 34 ) the diameter of which is smaller than the outer diameter of the inner bearing ring ( 6 i ).
4 . The sealing arrangement as recited in claim 1 , characterized in that, when in use, the baffle ( 32 , 32 ′, 32 ″) has an inner circumference or surface ( 34 ) the diameter D 2 of which is smaller than the distance D 1 from the oil level L to the axis of the flow machine.
5 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 , 32 ′) is arranged to rest against the radial side surface of the outer bearing ring ( 6 o ).
6 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 ′) is a separate circular ring arranged between the bearing cover ( 30 ) and the outer bearing ring ( 6 o ).
7 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 ″) is a separate circular ring arranged between the bearing ( 6 ) and the bearing cover ( 30 ).
8 . The sealing arrangement as recited in claim 1 , characterized in that the baffle ( 32 ) is a part of the bearing cover ( 30 ).
9 . The sealing arrangement as recited in claim 1 , characterized in that the gap ( 36 ) between the baffle ( 32 , 32 ′, 32 ″) and the inner bearing ring ( 6 i ) has a dimension of 0.2-0.7 mm.