A method of manufacturing a suction pipe for a multi-compressor device having a plurality of inlets, the suction pipe comprising a primary portion and a plurality of secondary portions arranged to receive fluid from the primary portion for supplying fluid in parallel to the inlets of a multi-compressor device. The method includes designing the suction pipe by: selecting a first dimension for the primary portion of the suction pipe, calculating a first fluid velocity for fluid in the primary portion based on the first dimension, and comparing the first fluid velocity to a first predetermined threshold; selecting a second dimension for the secondary portions, calculating a second fluid velocity for fluid in the secondary portions based on the second dimension, and comparing the second fluid velocity to a second predetermined threshold; and calculating a ratio of the first fluid velocity to the second fluid velocity.

Oil-injected multistage compressor device including a low-pressure compressor element (2) with a gas inlet (4a) for gas to be compressed and a gas outlet (5a) for low-pressure compressed gas and a high-pressure stage compressor element (3) with a gas inlet (4b) for low-pressure compressed gas and a gas outlet (5b) for high-pressure compressed gas. The gas outlet (5a) of element (2) is connected to inlet (4b) of element (3) via a conduit (6). The conduit (6) has a regulatable intercooler (9) configured to regulate the temperature at the gas inlet (4b) of the high-pressure stage compressor element (3) so that it is above the dew point. The intercooler (9) includes a regulatable air cooler and/or a regulatable water cooler, and is configured to adjust the temperature of the air or water by using a bypass conduit (16) and/or by screening off part of the intercooler (9).

A method, system, and computer-readable medium related to control of mud motors in drilling systems, of which the method includes measuring an eccentricity of rotation of a rotor in a stator of a mud motor using a rotor-position sensor, determining a torque of the mud motor based in part on the eccentricity, and selecting a fluid flow rate, a pressure, or both of fluid delivered downhole, through the mud motor, based in part on the determined torque.

Systems and methods are provided for pump systems that deliver optimized performance and efficiency. A method includes selecting a pump for the pump system. A maximum operating speed of the pump is determined, and its torque requirements are evaluated. A motor is selected to meet the torque requirements and a speed target is set for the motor. A speed reducer is sized for operation of the motor at the speed target and operation of the pump below the maximum speed, and the motor is coupled with the pump through the speed reducer.

The disclosure herein relates to device, for example a gear pump, for pumping fluid. The gear pump comprises a motor for driving a rotatable drive shaft; a drive gear configured to be driven by the drive shaft; an idler gear which meshes with the drive gear; an annular magnet disposed coaxially with the drive shaft and configured to rotate therewith; and a sensor for sensing rotation of the annular magnet and generating an output signal corresponding to a rotational position of the drive shaft.

A pump with variable suction/discharge amount and a transmission drive device and a driving method thereof. The pump is a rotary vane pump having a vane chamber body. The vane chamber body is composed of a fixed wall member, a movable wall member, a movable vane chamber sleeve and a vane rotor. The vane chamber is extendable/retractable in an axial direction of the vane rotor. At least two pumps are assembled in communication with each other to form a closed loop for the active pump to drive the passive pump. In operation, passive the vane chambers of the active pump and the passive pump are automatically extended/retracted and modulated until the driving force and the load resistance achieve a balanced state passive, the vane chambers and the rotational speeds of the active pump and the passive pump are automatically adjusted to be in inverse proportion to each other.

The present invention relates to an arrangement for detecting a delivery volume and/or a delivery flow, with a discontinuously operating pump (1), at least one outlet line (3) and/or one inlet line (2, 2-1, 2-2) and a passive valve (5, 5-1, 5-2), which is arranged in the outlet line (3) or the inlet line (2, 2-1, 2-2) and which has a valve seat (15-1, 15-2) and a valve head (16-1, 16-2), the valve (5, 5-1, 5-2) being closed in a first position of the valve head (16-1, 16-2) and being open in a second position of the valve head (16-1, 16-2) of the valve (5, 5-1, 5-2). The arrangement according to the invention is defined by a sensor (8, 8-1, 8-2), by means of which values can be detected which indicate whether the valve head (16-1, 16-2) is in the first or the second position, and by a computing unit (9) which is coupled to the sensor (8, 8-1, 8-2) and by means of which the volume delivered by the pump (1) and/or the delivery flow of the pump (1) can be calculated on the basis of the detected values of the sensor (8, 8-1, 8-2). The invention relates furthermore, to an extraction system for a plant protective with such an arrangement and to a method for detecting a delivery volume and/or a delivery flow of a discontinuously operating pump, which method can be carried out by this arrangement.

A method for controlling a compressor towards an unloaded state, in which the compressor includes a compressor element (2) with an inlet (5), in which in the unloaded state, a residual flow (QD) is suctioned via the inlet (5) towards and into the compressor element (2), and in which for a transition from a loaded state of the compressor to the unloaded state, the inlet (5) of the compressor element (2) is partially closed in successive discrete transitional steps.

A vane pump includes: a rotor configured to rotate under rotational force from a rotary shaft while supporting multiple vanes and including a curved surface portion with an arc shape centered on the rotary shaft and a rotor recess depressed from the curved surface portion toward a rotation center; a cam ring disposed so as to surround the rotor and including an inner peripheral surface facing the curved surface portion of the rotor; and an inner plate disposed on one end of the cam ring in an axial direction of the rotary shaft so as to cover an opening of the cam ring and including a suction inner recess depressed toward the rotation center relative to the curved surface portion of the rotor.

A positive displacement pump for pumping oil in a motor vehicle transmission comprises a pump stage that has a central kidney-shaped suction cavity and two kidney-shaped pressure cavities. Oil is selectively pumped via one kidney-shaped pressure cavity or the other kidney-shaped pressure cavity in accordance with the direction of rotation of the pump stage. This makes it possible to create, with little complexity, two operating stages for the positive displacement pump.