A method of manufacturing a power unit for a downhole drilling motor includes fabricating a stator that provides two or more stator lobes that define an internal profile, and fabricating a rotor that provides at least one rotor lobe that defines an external profile that both rotates and precesses within the internal profile during operation. At least one of an external geometry and an internal geometry of the rotor along all or a portion of the rotor may be varied to alter a stiffness and mass of the rotor and thereby optimize stiffness and force balancing with respect to the stator. The rotor may then be rotatably positioned within the stator and thereby optimize the functioning and reliability of the motor power unit, of the downhole drilling motor assembly, of associated downhole drilling equipment, and to enhance directional drilling tendency modelling and directional drilling trajectory control.

A method of manufacturing a power unit for a downhole drilling motor includes fabricating a stator that provides two or more stator lobes that define an internal profile, and fabricating a rotor that provides at least one rotor lobe that defines an external profile that both rotates and precesses within the internal profile during operation. At least one of an external geometry and an internal geometry of the rotor along all or a portion of the rotor may be varied to alter a stiffness and mass of the rotor and thereby optimize stiffness and force balancing with respect to the stator. The rotor may then be rotatably positioned within the stator and thereby optimize the functioning and reliability of the motor power unit, of the downhole drilling motor assembly, of associated downhole drilling equipment, and to enhance directional drilling tendency modelling and directional drilling trajectory control.

A hydraulic device can include two or more rings, a rotor having a plurality of vanes, and an adjuster. The two or more rings can be rotatably mounted within the hydraulic device and arranged adjacent one another configured for relative rotation with respect to one another. The rotor can be disposed for rotation about an axis within the two or more rings and can have a plurality of circumferentially spaced slots, each slot having at least one of the plurality of vanes located therein. The plurality of vanes can be configured to be movable between a retracted position and an extended position where the plurality of vanes work a hydraulic fluid introduced adjacent to the rotor. The adjuster can be configured to translate linearly to rotatably position the two or more rings relative to one another to increase or decrease a displacement of the hydraulic fluid between the rotor and the two or more rings.

A rotary pump exhibiting an adjustable specific delivery volume, the rotary pump including a housing featuring a delivery chamber for a fluid feed; a delivery rotor in the delivery chamber; a setting structure which surrounds the delivery rotor, a spring exerting a spring force which acts on the setting structure in a first setting direction; a setting pressure chamber for applying a setting pressure of a setting fluid, which acts counter to the spring force in a second setting direction, to the setting structure; and a housing abutment, wherein the setting structure includes: a recess on a circumference; and a counter abutment for the housing abutment in the recess.

A rotary pump exhibiting an adjustable specific delivery volume, the rotary pump including a housing featuring a delivery chamber for a fluid feed; a delivery rotor in the delivery chamber; a setting structure which surrounds the delivery rotor, a spring exerting a spring force which acts on the setting structure in a first setting direction; a setting pressure chamber for applying a setting pressure of a setting fluid, which acts counter to the spring force in a second setting direction, to the setting structure; and a housing abutment, wherein the setting structure includes: a recess on a circumference; and a counter abutment for the housing abutment in the recess.

The present document describes a pump (10) comprising a casing (12) that encloses a pumping group (14). On the casing (12) at least one inlet conduit for inletting a fluid (F) and at least one outlet conduit for outletting the fluid (F) are obtained. The pumping group (14) comprises a pair of mutually coupled gears, each mounted on a respective support shaft. The relative movement of a first gear with respect to the second gear defines a pumping chamber having variable volume inside the pumping group (14), so as to suck the fluid (F) from the suction conduit to expel it through the delivery conduit. A first support shaft (16) is operatively connected to an actuator assembly (18) so that the first gear can operate as a driving gear to set the second gear in rotation. The pump (10) comprises at least one element (20) for compensating the increase in volume of the fluid (F) and/or the increase in the pressures inside such a pump (10). The element (20) for compensating the pressure/volume is at least partially manufactured from a shape memory metal alloy having superelastic properties.

The present document describes a pump (10) comprising a casing (12) that encloses a pumping group (14). On the casing (12) at least one inlet conduit for inletting a fluid (F) and at least one outlet conduit for outletting the fluid (F) are obtained. The pumping group (14) comprises a pair of mutually coupled gears, each mounted on a respective support shaft. The relative movement of a first gear with respect to the second gear defines a pumping chamber having variable volume inside the pumping group (14), so as to suck the fluid (F) from the suction conduit to expel it through the delivery conduit. A first support shaft (16) is operatively connected to an actuator assembly (18) so that the first gear can operate as a driving gear to set the second gear in rotation. The pump (10) comprises at least one element (20) for compensating the increase in volume of the fluid (F) and/or the increase in the pressures inside such a pump (10). The element (20) for compensating the pressure/volume is at least partially manufactured from a shape memory metal alloy having superelastic properties.

A variable displacement vane pump includes: an adapter ring (a cam ring housing member) that defines a first fluid pressure chamber and a second fluid pressure chamber relative to an outer periphery of a cam ring, the cam ring being moved relative to a rotor by a differential pressure between the first fluid pressure chamber and the second fluid pressure chamber; a seal housing groove formed in an inner periphery of the adapter ring; and a slipper seal which is inserted into the seal housing groove and with which an outer periphery of the cam ring comes into sliding contact when the cam ring moves, whereby the slipper seal partitions the first fluid pressure chamber from the second fluid pressure chamber, wherein the slipper seal is formed in a thin plate shape having a square cross-section.

A variable displacement vane pump includes: an adapter ring (a cam ring housing member) that defines a first fluid pressure chamber and a second fluid pressure chamber relative to an outer periphery of a cam ring, the cam ring being moved relative to a rotor by a differential pressure between the first fluid pressure chamber and the second fluid pressure chamber; a seal housing groove formed in an inner periphery of the adapter ring; and a slipper seal which is inserted into the seal housing groove and with which an outer periphery of the cam ring comes into sliding contact when the cam ring moves, whereby the slipper seal partitions the first fluid pressure chamber from the second fluid pressure chamber, wherein the slipper seal is formed in a thin plate shape having a square cross-section.