Abstract: A centrifugal separator for separating a liquid heavy phase and light phase from a liquid feed mixture includes a drive member and a rotating part. The rotating part includes a centrifuge rotor enclosing a separation space and a sludge space. The centrifugal separator includes an inlet for receiving the liquid feed mixture into the centrifuge rotor, a first outlet for the liquid heavy phase and a second outlet for the liquid light phase. The centrifugal separator includes a conduit system for recirculating separated liquid heavy phase discharged from a first outlet to the sludge space within the centrifuge rotor without mixing the recirculated separated liquid heavy phase with the liquid feed mixture. Sludge outlets, other than the first and second outlets, discharge sludge separated from said liquid feed mixture. A method for separating a liquid heavy phase and a liquid light phase from a liquid feed mixture is also disclosed.

Abstract: A method for mounting a stack of separating discs in a centrifugal separator bowl comprising a bowl body and a bowl hood includes mounting and securing the stack of separating discs on a distributor; placing and rotatably fixing the distributor in the bowl body; mounting the bowl hood on the bowl body; arranging a compression tool for compressing the stack of separating discs; fastening the screw with a second threaded end in a first (threading) of the distributor; tightening said nut, in relation to said first threaded end of said screw in such a manner that said distributor is lifted to an upper position; fixing the distributor in its upper position; and dismounting the compression tool. A compression tool for performing the method includes a support, a screw and a nut in accordance to above. A centrifugal separator kit includes a centrifugal separator and the compression tool.

Abstract: A seal assembly for providing a seal between a first zone and a second zone includes a rotatable sealing member including a first sealing ring, a stationary sealing member including a second sealing ring and a device for bringing the first and second sealing rings into engagement with each other. The first and second sealing rings are arranged so that a double contact seal having at least one chamber arranged at a radial plane is formed upon engagement between the first and second sealing rings. The seal assembly further includes at least one fluid connection to the chamber. A centrifugal separator includes such a seal assembly.

Abstract: A centrifugal separator bowl, having a vertical rotational axis, the separator bowl defining a separation space, and including an upper bowl section having a first threading, the first threading having a first inner diameter and a first outer diameter and defining an upper surface, and a lower bowl section having a second threading corresponding to the first threading of the upper bowl section, the second threading having a second outer diameter and a second inner diameter and defining a lower surface. The upper surface of the first threading of the upper bowl section and the lower surface of the second threading of the lower bowl section form a screw connection.

Abstract: A centrifugal separator includes a casing which delimits a space which is sealed off from and having an under pressure in relation to the surroundings, by at least one seal. A rotor is arranged for rotation around a rotational axis and forms within itself a separation space. In the separation space, centrifugal separation of at least one higher density component and at least one lower density component from a fluid takes place during operation. At least one inlet extends into the rotor for introducing the fluid to the separation space. At least one first outlet extends from the rotor for discharge of at least one component separated from the fluid during operation. The rotor includes at least one second outlet extending from a portion of the separation space to the space for discharge of at least one higher density component separated from the fluid during operation.

Abstract: A seal assembly for providing a seal between a first zone and a second zone includes a rotatable sealing member including a first sealing ring, a stationary sealing member including a second sealing ring and a device for bringing the first and second sealing rings into engagement with each other. The first and second sealing rings are arranged so that a double contact seal having at least one chamber arranged at a radial plane is formed upon engagement between the first and second sealing rings. The seal assembly further includes at least one fluid connection to the chamber. A centrifugal separator includes such a seal assembly.

Abstract: A centrifugal separator includes a casing which delimits a space which is sealed off from and having an under pressure in relation to the surroundings, by at least one seal. A rotor is arranged for rotation around a rotational axis and forms within itself a separation space. In the separation space, centrifugal separation of at least one higher density component and at least one lower density component from a fluid takes place during operation. At least one inlet extends into the rotor for introducing the fluid to the separation space. At least one first outlet extends from the rotor for discharge of at least one component separated from the fluid during operation. The rotor includes at least one second outlet extending from a portion of the separation space to the space for discharge of at least one higher density component separated from the fluid during operation.

Abstract: A hermetic centrifugal separator includes a centrifuge rotor, which is arranged to rotate around a center axis and includes a casing which defines an inner separation space, a set of separation discs in the inner separation space, two or more channels which connect to the separation space and include one or more inlet channels for supply of a liquid mixture of components to be separated to the separation space and one or more outlet channels for discharge of a component. The separator includes a torque transmitting part around the center axis and fixedly connected to the centrifuge rotor and an outlet seal between the outlet channel and the rotating centrifuge rotor preventing entrainment of unwanted substances. The separator includes a pump arranged to provide pressure to feed the separated liquid through the outlet channel.

Abstract: A hermetic centrifugal separator for centrifuging components, contained in a liquid mixture and having different density, comprises a rotating centrifuge rotor, which is arranged to rotate around a centre axis and comprises a casing which defines an inner separation space, a set of separation discs which are provided in the inner separation space of the centrifuge rotor, at least two channels, which connect to the separation space and comprise at least one inlet channel for supply of the liquid mixture of components to be separated to the separation space and at least one outlet channel for discharge of a component separated during operation from the separation space, a torque transmitting part around the centre axis and fixedly connected to the centrifuge rotor adapted to be driven in such a way that the centrifuge rotor is brought to rotate, outlet sealing means arranged to seal between the outlet channel and the rotating centrifuge rotor preventing entrainment of unwanted substances.

Abstract: In a centrifugal separator a centrifugal rotor is connected to a vertical spindle, which is supported by a frame and journalled in a first bearing and a second bearing. The centrifugal separator is drivable by an electric motor, the stator of the motor being fixed to the frame such that it is radially immovable relative to it, whereas the rotor of the motor is radially movable together with the spindle. The gap between the rotor and the stator of the motor is dimensioned so that it permits the radial movability of the rotor.

Abstract: In a centrifugal separator for separating a product to a heavy phase and a light phase. The centrifuge rotor encloses a separating space. An inlet channel permits feeding of the product to the separating space. A first outlet channel permits discharge of the heavy phase from the separating space. The second outlet channel permits discharge of the light phase from the separating space. The centrifuge rotor includes a first chamber for collecting the heavy phase, a heavy phase channel, for feeding the heavy phase, and a nozzle member between the heavy phase channel and the first chamber for controlled feeding. The first paring member extends outwardly in the first chamber from the first outlet channel for discharge of the heavy phase. The second paring member extends outwardly in the first chamber.

Abstract: An entrainment device for a centrifugal rotor, which is rotatable about a central rotational axis, having a number of entrainment members arranged in said space for entrainment of entering liquid in the rotation of the centrifugal rotor. The entrainment device comprises a first component, which surrounds the rotational axis and has at least one first projection, which has a radial extension, and a second component, which surrounds the rotational axis and has at least a second projection, which also has a radial extension. The second component is axially insertable in said central space to a position, in which said second projection is present adjacent to said first projection. When the entrainment devices are in place in the central space, a locking member is applicable in releasable engagement with said projection so that the second component is prevented from moving axially relative the first component.

Abstract: In a particular type of centrifugal rotor for dividing a liquid mixture into one liquid phase having a low viscosity and one concentrate phase having a high viscosity, the concentrate phase on its way towards an outlet chamber (17) in the rotor has to flow through a vortex device (20). The vortex device has a property of admitting therethrough a larger flow of a liquid if this has a high viscosity than if it has a low viscosity. For making an operation for cleaning of the rotor and conduits for concentrate phase downstream of the rotor more efficient, a cleaning liquid, which has a low viscosity, is conducted not only through the vortex device (20) to said outlet chamber (17) for concentrate phase but to this outlet chamber (17) also through a separate passage (34). Thereby, it is guaranteed that a sufficient flow of cleaning liquid enters the concentrate outlet chamber (17) and from there can be pumped out of the rotor to the concentrate phase conduits downstream of the rotor.

Abstract: A device for the supply of a liquid under pressure to a flow passage (13) in a member in a shaft suspension unit (1) of a centrifugal separator, which has a stationary casing (3) and a unit, which is resiliently and oscillation dampingly suspended in the casing (3) by at least one elastical element (10), the member forming a part of the composed unit. To be able to supply liquid to the member in a sample manner with a certain controllable flow which is made sure under overpressure a first supply channel portion (19) is connected to a liquid source (16) for the supply of liquid under pressure extending through the stationary casing (3). To the first supply channel portion (19) there is connected a second supply channel portion (21) extending through the elastical element (10). A third supply channel portion (23) is connected to the second supply channel portion (21), extending through the non-rotatable part of the composed unit and having an outlet opening (24) in the flow passage (13).

Abstract: A simple but still effective sealing device to separate two openings (4, 5), which are arranged at a distance from each other in the outer casing (3) of a shaft suspension unit (1), which supports a shaft (2) of a centrifugal separator in a bearing (8, 9), the shaft extending axially through at least one opening (4) into a space surrounding the shaft (2) in the outer casing (3). The sealing device is provided with sealing elements (12, 13), one connected to the outer casing (3) and one connected to the shaft (2), which surround the shaft (2) and divide the space in two departments (15, 16) connected to one opening each (4, 5, respectively). The sealing elements form between themselves a narrow gap (14) surrounding the shaft (2), which prevents the flow of gas between the departments (15, 16).