A downhole tool includes an electric submersible pump to pump a well fluid to a surface of a borehole. The downhole tool includes a motor to power the electric submersible pump and a seal section to protect the motor from the well fluid. The seal section includes an elastomeric bag and a clamp at each end of the elastomeric bag to secure the elastomeric bag. The seal section includes an elastomeric bag protector secured around each clamp, wherein the elastomeric bag protector extends axially beyond a respective clamp to surround a tapered portion of the elastomeric bag above and below the clamp, and wherein the elastomeric bag protector has a sloped inner diameter that matches a profile of the tapered portion.

A vacuum pump and a damper for the vacuum pump are provided so as to increase vibration isolation in a twisting direction with a simple structure and prevent rupture of an O-ring and an elastic member by regulating a misalignment of flanges facing each other. Provided are a first flange and a second flange, each having a central opening, the flanges being shaped like rings opposed to each other; an O-ring and an intermediate ring that are disposed between the first flange and the second flange; O-rings disposed between the first flange and the intermediate flange and between the intermediate ring and the second flange; a plurality of elastic members that are disposed between the first flange and the second flange and are spread in the circumferential direction of central openings; and airtightness keeping means including positioning pins inserted into positioning holes sequentially provided on the first flange, the intermediate ring, and the second flange.

The application discloses a multipurpose transfer pump free of secondary water filling, which comprises a cover plate, a water filling plug, a pump body, an impeller, a pump body flange and a motor, the pump body flange is provided at an end portion of the motor, the pump body is provided on a front surface of the pump body flange, a volute chamber corresponding to the impeller is provided in a back surface of the pump body in an inwards recessed manner. In this way, the multipurpose transfer pump free of secondary water filling disclosed by the application can achieve a self-priming effect without filling water into the pump body when the motor works for a second time, thus improving the impeller lubricating effect.

A labyrinth section for a submersible pump includes an outer housing having a coupling sealingly engaged at each longitudinal end of the outer housing. An inner tube is sealingly engaged at each end to one of the couplings to define a sealed annular space. A plurality of labyrinth tube sections are disposed in the annular space, each comprising labyrinth tubes engaged with end plates. A plurality of the labyrinth tube sections enable movement of fluid through the labyrinth tubes, spaces external to the labyrinth tubes and between the end plates to fill the annular space. One of the labyrinth tube sections constrains fluid to move only within the labyrinth tubes and wherein the inner tube between the end plates of the one of the labyrinth tubes comprises a fluid port into an interior of the inner tube.

A compression ring for a shrouded compressor including a radially inner surface having one or more areas configured to mate flush with one or more portions of a radially outward surface of a shroud of the shrouded compressor, a radially outer surface located opposite the radially inner surface, a labyrinth seal located on the radially outer surface, a groove located within the radially inner surface, and a load ring located within the groove.

A centrifugal pump assembly includes a pump head, a pump base defining a pump inlet and a pump outlet, a fluid outlet channel from the pump head to the pump outlet, impellers, defining an impeller fluid channel between an impeller inlet and outlet and connected with one of rotor shaft segments including a positive fit coupling for torque transfer between at least two rotor shaft segments, and one or more pump stage housing segments arranged between the pump base and the pump head. The pump stage housing segments have a structure defining a guide passage for receiving pumped fluid from the impeller outlet of the impellers and for guiding pumped fluid to the impeller inlet of another one of the impellers or to the pump head. The pump stage housing segments each have a structure defining at least a part of a wall section of the fluid outlet channel.

A hydraulic machine includes a first member (1) having a first structure (2) for a hydraulic medium opening in a first interface surface (3) and a second member having a second structure for the hydraulic medium opening in a second interface surface is described, the first interface surface (3) being in contact with the second interface surface, wherein at least one of the members (1) is provided with a support element (6) surrounding the member (1). Such a machine should have a good efficiency. To this end the support element (6) has a strength varying in circumferential direction around the member (1) and/or in thickness direction in a middle region of the member (1).

A centrifugal compressor is shown, comprising: an impeller; a rotatably mounted diffuser surrounding the impeller; and a driving arrangement configured to drive the impeller and diffuser to rotate in opposing directions.

A centrifugal pump sealing structure is provided. In one aspect, one sealing member is provided at a position where leakage paths from a fluid compression space between a middle housing and a cover and an electric component installation space between the middle housing and a lower housing are connected. Then, the two spaces are sealed. The number of sealing members is reduced, so that the internal structure becomes simpler and the assembly of the sealing member becomes easier.

A ceiling-inserted fan includes a case having an air inlet on a bottom surface of the case and an air outlet on a side surface of the case, an adapter plate having a rectangular opening and forming at least part of the side surface of the case, a duct-connecting adapter protruding outward the adapter plate and an air-sending part for directing air from the air inlet to the air outlet. The duct-connecting adapter is separated from the adapter plate and includes a sealing section that contacts with a peripheral section of the rectangular opening inside the case and a locking section that contacts with the peripheral section of the rectangular opening outside the case. The sealing section and the locking section removably holds the peripheral section.