An apparatus for a submersible screw pump includes a cylindrical rotor located inside of a cylindrical stator. The rotor has a screw thread formed in an opposite direction in relation to screw threads of the stator. The external surface of the rotor has a curvilinear shape and the internal surface of the stator has semicircular shapes without rectangular edges. These surface features of the rotor and stator obtain high speed performance for the apparatus with reduced vortices. A gap between the internal surface of the stator and the external surface of the rotor is 0.1-0.2 millimeters. A unloading thrust bearing is attached to a rotor shaft positioned between an intake thrust bearing and the intake end of the rotor. A cavity in the unloading thrust bearing is configured to receive production fluid from the discharge end of the rotor.

A water lubrication air compression system disposes an lubricant heat dissipation system at a bearing chamber close to the high pressure end of the compressor for cooling and circulating lubricant due to the rise of temperature during operation of the compressor, hence enhancing the ability and stability of the compressor. On the other hand, a negative pressure system is connected to the air chambers between the oil lubrication and the water lubrication of the compressor in order to provide a negative pressure. If any leak of water vapor at the compressor chamber or oil vapor at the bearing chamber, the negative pressure system is able to produce a negative pressured condition toward the sealing structure so that the oil lubrication can be effectively isolated from the water lubrication and inter-contamination between the lubricant and water can be avoided.

A water lubrication air compression system disposes an lubricant heat dissipation system at a bearing chamber close to the high pressure end of the compressor for cooling and circulating lubricant due to the rise of temperature during operation of the compressor, hence enhancing the ability and stability of the compressor. On the other hand, a negative pressure system is connected to the air chambers between the oil lubrication and the water lubrication of the compressor in order to provide a negative pressure. If any leak of water vapor at the compressor chamber or oil vapor at the bearing chamber, the negative pressure system is able to produce a negative pressured condition toward the sealing structure so that the oil lubrication can be effectively isolated from the water lubrication and inter-contamination between the lubricant and water can be avoided.

A compressor system is provided that includes a contact cooled compressor and a coolant separator. The coolant separator is used to remove coolant fluid from a compressed flow stream produced by the contact cooled compressor during its operation. The coolant separator routes the removed coolant fluid back to the contact cooled compressor for further use. In some forms the coolant fluid is cooled prior to delivery back to the compressor. A stop valve can be provided in the coolant fluid return line to halt the flow of the fluid. A pressure sensitive member can be disposed to sense pressure of the coolant fluid that has been routed past the stop valve. Operation of the compressor can be changed as a result of the sensed pressure from the pressure sensitive member. Information from a temperature sensitive member can also be used to change operation of the compressor.

A compressor system is provided that includes a contact cooled compressor and a coolant separator. The coolant separator is used to remove coolant fluid from a compressed flow stream produced by the contact cooled compressor during its operation. The coolant separator routes the removed coolant fluid back to the contact cooled compressor for further use. In some forms the coolant fluid is cooled prior to delivery back to the compressor. A stop valve can be provided in the coolant fluid return line to halt the flow of the fluid. A pressure sensitive member can be disposed to sense pressure of the coolant fluid that has been routed past the stop valve. Operation of the compressor can be changed as a result of the sensed pressure from the pressure sensitive member. Information from a temperature sensitive member can also be used to change operation of the compressor.

A rotor for a compressor system includes a rotor body having a coolant manifold with an inlet runner and a plurality of coolant supply conduits extending from the inlet runner toward an inner heat exchange surface. The coolant supply conduits may have a circumferential and axial distribution, and extend through struts enhancing stiffness in the rotor body.

A rotor for a compressor system includes a rotor body having a coolant manifold with an inlet runner and a plurality of coolant supply conduits extending from the inlet runner toward an inner heat exchange surface. The coolant supply conduits may have a circumferential and axial distribution, and extend through struts enhancing stiffness in the rotor body.

A conical screw compressor or pump comprises an inner element configured to rotate around a first axis and an outer element configured to rotate around a second axis. An outer surface of the inner element and an inner surface of the outer element comprise cooperating grooves and teeth that intermesh on rotation. The first axis and the second axis are each stationary and the first axis is inclined relative to the second axis. The inner element and the outer element are configured to be, in operation, synchronously rotated, thereby to reduce or eliminate force exerted by the inner element on the outer element or vice versa.

A conical screw compressor or pump comprises an inner element configured to rotate around a first axis and an outer element configured to rotate around a second axis. An outer surface of the inner element and an inner surface of the outer element comprise cooperating grooves and teeth that intermesh on rotation. The first axis and the second axis are each stationary and the first axis is inclined relative to the second axis. The inner element and the outer element are configured to be, in operation, synchronously rotated, thereby to reduce or eliminate force exerted by the inner element on the outer element or vice versa.

A submersible multi-stage labyrinth-screw pump, having a rotor shaft; an end seal for the rotor shaft; an axial unloading unit integrated into the end seal of the rotor shaft; a lower radial bearing; a longitudinal channel, which connects a high-pressure zone at an exit for the rotor and the chamber of the axial unloading unit of the shaft, the axial unloading unit comprising a thrust block with a wear-resistant insert, a thrust collar, mated with a segment of the end seal, the end seal housing, a spring, a thrust ring, and a seat sleeve of the end seal, wherein the end seal of the rotor shaft's axial unloading unit operates as follows, when high pressure appears in the chamber of the rotor shaft's axial unloading unit, the fluid is kept from unproductive flows by hermetic contact of the ground insert of a segment and a seat of the end seal.