A multistage centrifugal pump has a foot part (2) and a head part (9), between which pump stages are integrated. The head part (9) and the foot part (2) are connected via tie-rods (11) which with one end are fastened on the head part (9) and with the other end are fastened on the foot part (2). The tie-rods (11) at one end comprise a thread (14), with which they are tightened on the head part (9). The tie-rods (11) are formed from sheet metal. At the end opposite the thread, the tie-rods include a recess, with which recess the tie-rods are each positively fixed on the foot part (2), at least in the tensile direction (22).

A fluid processing machine that includes a stator capable of generating an electromagnetic field and a first rotor section having at least one impeller and at least one permanent magnet. The stator is configured to electromagnetically engage with the first rotor section so as to rotate the first rotor section about a central axis in a first rotational direction. Further rotor sections can also be included that are induced to rotate in the first rotational direction. Other rotator sections with impellers and permanent magnets can also be included that are driven in a second, contra-rotating, direction by a second stator. Several of the fluid processing machine can be distributed within a surface system or subsea system that transports produced fluid from wells to a surface facility.

A horizontal pumping system has a motor, a pump driven by the motor and a priming module. The pump has a discharge on a first end of the pump, a suction end on a second end of the pump, and a plurality of stages between the suction end and the discharge. Each of the plurality of stages includes an impeller and a diffuser that encases the impeller. Each diffuser is an independent pressure vessel. The priming module may be a wet priming module or a dry priming module. The priming module permits the use of the horizontal pumping system in many applications in which the liquid is not naturally present at the pump intake.

There is provided a multistage centrifugal fluid machine capable of improving efficiency of an operation for assembling an inner casing to a high pressure side head flange. The multistage centrifugal fluid machine 100 includes a rotor 3 provided with a plurality of impellers (41 to 81) in an axial direction, a cylindrical outer casing 2, and an inner bundle 1 that is fitted with the outer casing 2 to form a flow passage for the working fluid. The inner bundle 1 includes a high pressure side head flange 11, a low pressure side head flange 12, and an inner casing 5 disposed between the high pressure side head flange 11 and the low pressure side head flange 12. The high pressure side head flange 11 and the inner casing 5 are fastened with a first bolt 142 via an elastic body 144.

A first fluid rotor that has a first fluid intake end and a first fluid discharge end. The first fluid rotor includes a shaft and an impeller. A second fluid rotor that has a second fluid intake end and a second fluid discharge end. The second fluid rotor is rotatably coupled to the first fluid rotor to rotate in unison with the first fluid rotor along a shared rotational axis. The first fluid intake end and the second fluid intake end are facing opposite directions. The second fluid rotor includes a second shaft and a second impeller. A first fluid stator surrounds the first fluid rotor. The first fluid stator is aligned along the rotational axis. The first fluid rotor and the first fluid stator form a first fluid stage. A second fluid stator surrounds the second fluid rotor. The second fluid stator is aligned along the rotational axis. The second fluid stator and the second fluid rotor form a second fluid stage. A flow crossover sub is positioned between the first fluid stage and the second fluid stage. The flow crossover sub defines flow passages that fluidically connect the first fluid stage and the second fluid stage. An outer housing surrounds the first fluid stator, the second fluid stator, and the flow crossover sub.

A vertical pump includes: a rotary shaft; multi-stage impellers; a casing accommodating the multi-stage impellers; a mechanical seal provided in a penetration part of the casing for the rotary shaft; a balance sleeve, the balance sleeve being positioned between a final stage impeller of the multi-stage impellers and the mechanical seal in the penetration part for the rotary shaft; an intermediate chamber provided between the rotary shaft and the casing and provided on an opposite side of the multi-stage impellers across the balance sleeve in an axial direction of the rotary shaft, the intermediate chamber communicating with an intermediate stage impeller among the multi-stage impellers; a low pressure chamber provided between the rotary shaft and the casing, the low pressure chamber communicating with a low pressure side compared to the intermediate chamber; and a partition wall part dividing the intermediate chamber and the low pressure chamber.

A pump assembly (1) includes a rotor shaft, a pump base (3), a pump housing (5), a motor housing (9) enclosing a motor for driving the rotor shaft, and a motor stool (7) that includes a motor coupling portion (13) and a pump coupling portion (15). The pump housing encloses one or more impeller stages (10) arranged between the motor stool and the pump base. The motor stool is clamped to the pump base by at least two tie rods (17). The motor stool includes at least two fixation protrusions (39) each having a protrusion end (41) in the motor coupling portion. Each of the tie rods is fixed to the motor stool by way of a fastener (37) at least partially extending through one of the fixation protrusions. Each fastener is only accessible when the motor housing is decoupled from the motor coupling portion of the motor stool.

A surface pumping system has a motor and a pump driven by the motor. The pump has a discharge on a first end of the pump, a suction end on a second end of the pump, and a plurality of stages between the suction end and the discharge. Each of the plurality of stages includes an impeller and a diffuser that encases the impeller. Each diffuser is an independent pressure vessel. In some embodiments, the diffuser and impeller in each stage are large and configured for use in low net positive suction head (NPSH) applications.

A coaxial pump or turbine module includes an integral, modular motor or generator comprising a magnet structure containing radial or axial permanent magnets and/or induction coils detachably fixed to a rotor, and a stator housing detachably fixed to the module housing. Working fluid is directed axially through a flow path symmetrically distributed within an annulus formed between the module housing and the stator housing. The stator housing can be cooled by the working fluid, or by a cooling fluid flowing between passages of the flow path. The flow path can extend over substantially a full length and rear surface of the stator housing. A plurality of the modules can be combined into a multi-stage apparatus, with rotor speeds independently controlled by corresponding variable frequency drives. Embodiments include guide vanes and/or diffusers. The rotor can be fixed to a rotating shaft, or rotate about a fixed shaft.

A pump assembly with improved sealing includes an outer housing and an insert arranged therein. The insert includes a rotatable shaft and at least two pressure stages. Each pressure stage has a housing, an impeller, and a seal that separates a first pressure chamber from a second pressure chamber. At least one of the pressure stage housings includes a first casing part having a first region having an enlarged inner diameter and a second region having a reduced inner diameter, and a second casing part having at least one first portion having a reduced outer diameter and a second portion having an enlarged outer diameter. The first region surrounds the first portion and at least partially surrounds the second portion, such that an annular chamber is formed between the first casing part and the second part, with the annular chamber being connected to the second pressure chamber.