The present invention concerns a cooling apparatus for subsea applications with a shell and tube heat exchanger. The heat exchanger includes a longitudinal shell. The shell forms a cavity with a fluid inlet port and fluid outlet port. A bundle of tubes extends from an inlet plenum chamber with an inlet port and into the shell on the same side of the shell as a bundle of tubes extending from an outlet plenum chamber with an outlet port. At least one tube sheet seals against the shell cavity and the inlet and outlet plenum chambers. The bundle of tubes extending from the inlet plenum chamber is in fluid connection with the bundle of tubes extending from the outlet plenum chamber. A retrievable pump module with a sealed pump module housing is placed adjacent the heat exchanger and includes a motor driving an ambient sea water pump.

The present invention concerns a cooling apparatus for subsea applications with a shell and tube heat exchanger. The heat exchanger includes a longitudinal shell. The shell forms a cavity with a fluid inlet port and fluid outlet port. A bundle of tubes extends from an inlet plenum chamber with an inlet port and into the shell on the same side of the shell as a bundle of tubes extending from an outlet plenum chamber with an outlet port. At least one tube sheet seals against the shell cavity and the inlet and outlet plenum chambers. The bundle of tubes extending from the inlet plenum chamber is in fluid connection with the bundle of tubes extending from the outlet plenum chamber. A retrievable pump module with a sealed pump module housing is placed adjacent the heat exchanger and includes a motor driving an ambient sea water pump.

An apparatus, system and method for pumping gaseous fluid are described. The centrifugal pump of the invention homogenizes at least a portion of the gas and liquid contained in produced well fluid thereby improving the efficiency of the pump in electric submersible pump (ESP) applications and decreasing the downtime of the ESP system. The impeller of the invention comprises an increased inlet area. The centrifugal pump of the invention comprises a single shroud located on the bottom side of an impeller, an increased inlet area of the impeller and an increased clearance gap between the impeller and a diffuser. One or more truncated vanes extend substantially upstream from the single shroud, wherein each truncated vane sits at a mid-pitch location between untruncated vanes starting from the bottom side of the impeller.

The present invention is a pump used for applications where a solid is present in wastewater and other liquids that requires cutting and reduction in size so as to pass the solid through the inlet to the outlet of the pump. The pump has a pump casing with an inlet and an outlet formed therein. A drive unit rotates a drive shaft extending axially through the pump casing to an impeller and a cutter bar. The pump is further configured with a radial cutter ring assembly positioned adjacent the cutter bar and the inlet providing a shredding cutting action of solids between the rotating cutter bar sliding past a radial cutter ring assembly held stationary, e.g. cutting blades formed in an edge of the cutter bar rotate across an internal surface of the radial cutter ring assembly. The pump also has an axial cutter ring assembly with one or more blades forming openings adapted for the passage of solids from the inlet to the outlet to provide a shearing cutting action of solids by a rotation of an upper surface of the cutter bar sliding past an axial cutting surface of the blades of the axial cutter ring assembly. The shred and shear pump may be configured with a plurality of slots on the internal surface of the radial cutter ring assembly to hold woven fibrous material for the shredding cutting action. The pump also features improved optimized flow, cutting and reducing solids in the form of woven fibrous materials, and adjustability of the cutter housing for precision and wear adjustment.

A dry-type cable wire outlet device for a submersible electrical pump includes a wire outlet box positioned in a wellbore, a cable protection pipe, a wire outlet sealing device and a cable. The wire outlet box is connected to the top of a submersible electrical pump. One end of the cable protection pipe is connected to the top of the wire outlet box, and the other end extends out of the well cover of the wellbore. The cable is positioned in the cable protect pipe and connected with the submersible electrical pump through the wire outlet box. The wire outlet sealing device is connected to the well cover, and an end of the cable protection pipe extending outside the well cover is positioned in the wire outlet sealing device. When the device is in use, the opening at the top end of the cable protection pipe is no longer exposed.

An electrical submersible pump assembly has a thrust bearing mechanism with first and second thrust runners axially and rotationally secured to the shaft and located within a housing. First and second thrust receiving structures are rigidly mounted in the housing to receive thrust from the first and second thrust transferring devices. A deflectable member located in the first thrust transfer thrust device decreases in axial thickness in response to thrust of a selected level. The second thrust transfer thrust device has an axial length less than an axial distance from the second thrust receiving structure to the second thrust runner, defining an initial axial gap. During operation of the pump, the shaft and the first and second thrust runners move axially a limited extent, closing the gap and transferring thrust from the second thrust transfer device to the second thrust receiving structure.

An electrical submersible pump assembly has a thrust bearing mechanism with first and second thrust runners axially and rotationally secured to the shaft and located within a housing. First and second thrust receiving structures are rigidly mounted in the housing to receive thrust from the first and second thrust transferring devices. A deflectable member located in the first thrust transfer thrust device decreases in axial thickness in response to thrust of a selected level. The second thrust transfer thrust device has an axial length less than an axial distance from the second thrust receiving structure to the second thrust runner, defining an initial axial gap. During operation of the pump, the shaft and the first and second thrust runners move axially a limited extent, closing the gap and transferring thrust from the second thrust transfer device to the second thrust receiving structure.

A system (16) for pumping a fluid, comprising: a pump (17) comprising a suction side (18) and a discharge side (19); a motor (20) for driving the pump, which motor is drivingly connected to the pump via a shaft (21); a return line (23) providing a feed-back conduit for the fluid from the discharge side to the suction side; a control valve (24) controlling the flow of the fluid through the return line; and a first sensor device (27) for monitoring a first system parameter which is a function of the differential pressure across the pump. The system further comprises: a second sensor device (28) for monitoring a second system parameter which is a function of the torque of the pump; and a control unit (25) arranged to: receive monitored first system parameter values from the first sensor device and, for each monitored first system parameter value, identify a minimum allowable second system parameter value; receive monitored second system parameter values from the second sensor device and, for each monitored second system parameter value, compare the monitored second system parameter value with the identified minimum allowable second parameter value; and regulate the control valve such that the monitored second parameter value does not fall below the minimum allowable second parameter value. A method of operating such a system is also disclosed.

A system (16) for pumping a fluid, comprising: a pump (17) comprising a suction side (18) and a discharge side (19); a motor (20) for driving the pump, which motor is drivingly connected to the pump via a shaft (21); a return line (23) providing a feed-back conduit for the fluid from the discharge side to the suction side; a control valve (24) controlling the flow of the fluid through the return line; and a first sensor device (27) for monitoring a first system parameter which is a function of the differential pressure across the pump. The system further comprises: a second sensor device (28) for monitoring a second system parameter which is a function of the torque of the pump; and a control unit (25) arranged to: receive monitored first system parameter values from the first sensor device and, for each monitored first system parameter value, identify a minimum allowable second system parameter value; receive monitored second system parameter values from the second sensor device and, for each monitored second system parameter value, compare the monitored second system parameter value with the identified minimum allowable second parameter value; and regulate the control valve such that the monitored second parameter value does not fall below the minimum allowable second parameter value. A method of operating such a system is also disclosed.

A method of operating a system (16) for pumping a fluid, which system comprises: a pump (17) for pumping the fluid; and a variable speed motor (20) for driving the pump (17). The method comprises the steps of: identifying a first system parameter (PI); identifying a second system parameter (P2) which is a function of the torque of the pump; setting a target value (P1.sub.0) for a first system parameter; monitoring the first system parameter (PI); establishing a target value (P2o) for the second system parameter based on the difference between the target value and the measured value of the first system parameter; monitoring the second system parameter; and regulating the rotational speed of the pump such that the difference between the monitored value and the target value of the second system parameter is minimised. A system for implementing the method is also disclosed.