A bearing oil feeding amount is appropriately controlled with respect to specifications of a discharge pressure (bearing load) and a rotation speed. A gas compressor has: a compressor main body that compresses gas and has a rotor; a bearing for supporting the rotor onto a compressor main body casing; an oil case that stores a lubricating oil to be supplied to the bearing; a lubricating oil pipe through which the lubricating oil is circulated from the oil case to the bearing; an oil pump that pumps the lubricating oil from the oil case to the bearing via the lubricating oil pipe; a flow amount control means for adjusting an amount of lubricating oil that circulates through the lubricating oil pipe; an electric motor that supplies power to the rotor; an inverter that outputs a rotation frequency of the electric motor; a pressure sensor that detects the discharge pressure of the compressor main body; and a control unit that determines a lubricating oil supply amount to the bearing on the basis of the load on the bearing corresponding to the pressure detected by the pressure sensor and the rotation speed of the rotor corresponding to the rotation frequency output by the inverter, and that controls the flow amount control means on the basis of the lubricating oil supply amount.

A fault diagnosis device for a fluid feed system comprises a first acquiring part acquiring values as a fluid pressure and pump rotational speed before fluid injection, a second acquiring part acquiring values as a fluid pressure and pump rotational speed during fluid injection, a pump rotational speed difference calculating part calculating a pump rotational speed difference comprising a difference between a pump rotational speed during fluid injection and a pump rotational speed before fluid injection when the fluid pressure before fluid injection and the fluid pressure during fluid injection match, and an abnormality judging part judging if an abnormality has occurred in a flow rate of fluid injected from an injection device based on the pump rotational speed difference.

Systems and methods for compressor unloading detection are provided and include a compressor having a compression mechanism. A controller determines a predicted discharge temperature of the compressor, receives an actual discharge temperature of the compressor, and compares the predicted discharge temperature with the actual discharge temperature. The controller also compares a speed of the compressor with a speed threshold and detects unloading of the compression mechanism based on the comparison of the predicted discharge temperature with the actual discharge temperature and based on the comparison of the speed of the compressor with the speed threshold. The controller performs at least one of generating an alert and a remediating action in response to detecting the unloading of the compression mechanism.

Systems and methods are disclosed of monitoring performance of an incompressible fluid system. The system has a positive displacement pump and a high bandwidth pressure sensor. A method comprises sensing a pressure of the fluid with the pressure sensor, determining pump ripple frequency and hence the speed of the positive displacement pump, calculating the pump flow rate, determining a flow restriction of the fluid system based on the pressure and flow, and assessing or trending the fluid system flow restriction.

Systems, methods, and computer-readable mediums are provided for improving the efficiency of a filter-type oil separator in a cooling system including a compressor that pumps a mixture of lubricating oil and refrigerant through the filter-type oil separator. The filter type oil separator is configured to receive a first portion of the mixture from the compressor, and a bypass line is configured to bypass a second portion of the mixture around the filter-type oil separator. The bypass line ensures a sufficient amount of oil is present in the compressor.

In order to improve a machine for depressurizing or compressing substantially gaseous media, comprising a machine casing and at least one screw rotor, which is arranged in a screw rotor bore in the machine casing, extends between a low-pressure side and a high-pressure side of the screw rotor bore, cooperates with the substantially gaseous medium and is mounted on both sides in the machine casing by means of a respective bearing set, and a motor/generator unit that is coupled or couplable to the at least one screw rotor, it is proposed that the at least one screw rotor should be provided with at least one axial support bearing that axially supports the at least one screw rotor such that a high-pressure end face of the at least one screw rotor is guided, without making contact, to an end wall, which faces this end face, of the machine casing that receives the at least one screw rotor.

A variable capacity screw compressor comprises a suction port, at least two screw rotors and a discharge port being configured in relation to a selected rotational speed that operates at least one screw rotor at an optimum peripheral velocity that is independent of a peripheral velocity of the at least one screw rotor at a synchronous motor rotational speed for a rated screw compressor capacity. A motor is configured to drive the at least one screw rotor at a rotational speed at a full-load capacity that is substantially greater than the synchronous motor rotational speed at the rated screw compressor capacity. A variable speed drive receives a command signal from a controller and generates a control signal that drives the motor at the selected rotational speed.

Techniques are provided for protecting a twin screw positive displacement pump, that include a signal processor that receives signaling containing information about power, torque, speed, viscosity and specific gravity related to the operation of the twin screw positive displacement pump; and determines whether to enter an enhanced pump protection mode for the twin screw positive displacement pump based on a relationship between an actual corrected tune ratio and a tuned ratio set point (Tune Ratio SP). In operation, the signal processor determines if the actual corrected tune ratio is<=the actual corrected tune ratio set point (Tune Ratio SP), and if so, then enters the enhanced pump protection mode, else continues to use a basic pump protection mode, and also determines the actual corrected tune ratio based on a ratio of an actual corrected torque (TAcorr) divided by a tuned corrected torque (TTcorr) at a specific operating speed.

A fluid pump includes a motor disposed within an outer housing. The motor includes a stator and a rotor in electromagnetic communication with the stator. Windings are disposed on the stator that receive an electric current for defining the electromagnetic communication. A pump element is attached to the rotor via a drive shaft. The pump element operates with the rotor to deliver a fluid through a hydraulic fluid path. A plurality of sensors measure information related to at least one of the stator, the windings, the rotor, the pump element, the fluid and the hydraulic fluid path. A controller is in communication with the windings for delivering the electric current to the windings. The controller is also in communication with the plurality of sensors for measuring and recording the information and communicating this information to one of an external memory and an external controller.

A pump device includes: a variable capacity-type pump unit configured to include an inner rotor having a plurality of external teeth , an outer rotor having a plurality of internal teeth meshing with a portion of the plurality of external teeth of the inner rotor, a housing, a suction port and a discharge port, an adjustment member adjusting a discharge pressure of a fluid, a biasing mechanism biasing the adjustment member, a control flow passage causing a fluid pressure from the discharge port to be applied to the adjustment member, a solenoid valve adjusting the fluid pressure applied to the adjustment member, a bypass flow passage, and a relief valve; a rotation speed sensor measuring a rotation speed of a drive source; and a control unit controlling the solenoid valve.