US 11,654,444 B2
Screen-type screw centrifuge
Dieter Scherer, Vierkirchen (DE); and Franziska Zhu, Vierkirchen (DE)
Assigned to Andritz Separation GmbH, Vierkirchen (DE)
Filed by Andritz Separation GmbH, Vierkirchen (DE)
Filed on Jul. 29, 2022, as Appl. No. 17/877,675.
Claims priority of application No. 21189098 (EP), filed on Aug. 2, 2021.
Prior Publication US 2023/0034543 A1, Feb. 2, 2023
Int. Cl. B01D 33/72 (2006.01); B01D 33/067 (2006.01); B04B 3/04 (2006.01)
CPC B04B 3/04 (2013.01) [B01D 33/067 (2013.01); B01D 33/72 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A screen-type screw centrifuge comprising:
a screw drive shaft extending along an axial axis;
a screw hub fixed to an axial end of the screw drive shaft;
a hollow screw main body having a first screw main body axial end portion and a second screw main body axial end portion and which extends axially along the axial axis from the first screw main body axial end portion to the second screw main body axial end portion in the direction opposite to a second axial end of the screw drive shaft and which comprises a screw main body circumferential wall extending around the axial axis, wherein the hollow screw main body is detachably fixed at the first screw main body axial end portion to the screw hub with at least one tightening means by which the screw main body and the screw hub are tightened against each other; and
a ring-shaped annular-gap cover having a central opening for receiving a feed line for feeding material to be centrifuged into the interior of the screw main body and which extends from the screw main body circumferential wall to the central opening to cover an annular gap between the received feed line and the screw main body circumferential wall when the feed line is inserted into the opening, and
wherein the at least one tightening means has a tool engagement portion facing the second screw main body axial end portion,
wherein at least one axial access channel is formed radially between the screw main body circumferential wall and the annular-gap cover, through which the tool engagement portion of the at least one tightening means is axially accessible from the second screw main body axial end portion,
wherein the at least one tightening means is formed as an axial tightening means and the screw main body and the screw hub are placed axially one behind the other and are axially tightened to each other by the at least one axial tightening means,
wherein a screw main body annular flange is formed by and/or on the screw main body circumferential wall at the first screw main body axial end portion, which extends around the axial axis and via which the screw main body is detachably fixed at the first screw main body axial end portion to a hub annular flange of the screw hub, which extends around the axial axis,
wherein the screw main body annular flange and the hub annular flange are placed axially one behind the other and are axially tightened together by the at least one axial tightening means,
wherein the annular-gap cover includes a cover annular flange extending around the axial axis, the cover annular flange
is placed axially between the screw main body annular flange and the hub annular flange, and
is axially tightened together with the screw main body annular flange and the hub annular flange by the at least one axial tightening means,
wherein the annular-gap cover includes a hollow cylindrical or hollow conical cover body including a cover circumferential wall extending around the axial axis,
wherein the axial access channel is formed as an annular channel extending radially around the axial axis between the cover circumferential wall and the screw main body circumferential wall,
wherein the screen-type screw centrifuge further comprises a rotatably supported screen drum having a screen drum circumferential wall, by which the screw main body is surrounded around the axial axis and which is equipped with a screen, and having an adjusting ring disk which extends around the axial axis and which is axially placed between the screw main body annular flange and the hub annular flange, and by which a radial gap between the screw main body and the screen drum circumferential wall is adjustable, and
wherein the adjusting ring disk is axially tightened by the at least one axial tightening means together with the screw main body and the screw hub, and together with the screw main body annular flange and the hub annular flange.