An electric device having a casing with an air-outlet, and a main unit disposed inside the casing, includes a first temperature sensor configured to detect the temperature inside the casing, a second temperature sensor installed in the vicinity of the air-outlet, and an electric fan configured to generate an airflow from the air-outlet toward the inside of the casing at the time of the low-temperature startup such that the temperature detected by the first temperature sensor is lower than a preset first threshold value, and the temperature detected by the second temperature sensor is higher than the temperature detected by the first temperature sensor.

A gas compressor system is provided to operate at a well site and to inject a compressible fluid into a wellbore in support of a gas-lift operation. Methods and systems are provided that allow for the automated individual control of discharge temperatures from coolers for gas injection, in real time, wherein the temperature control points of the first and/or second stage cooler discharges are automatically controlled by a process controller in order to push heat produced by adiabatic compression to a third or final compression stage. In this way, discharge temperatures at the final stage are elevated to maintain injection gaseous mixtures in vapor phase.

A process for compressing a gaseous fluid comprising a step (a) of injecting refrigerant during which a refrigerant substance is sprayed into the gaseous fluid to be compressed, and also a compression step (b), during which the passage of said gaseous fluid loaded with refrigerant substance is forced through said compressor in order to compress said gaseous fluid, the mass flow rate (Q3) of the refrigerant substance injected into the gaseous fluid represents between 1% and 5% of the mass flow rate of the gaseous fluid to be compressed, and the refrigerant substance is sprayed in the form of particles having a maximum dimension of less than or equal to 25 m, and preferably less than or equal to 10 m.

In one embodiment, a compressor clearance control system is provided. The compressor clearance control system includes a cooling air source, a compressor casing, and a cooling air flowpath defined through the compressor casing. The flowpath includes an inlet configured to receive cooling air from the cooling air source and an outlet configured to exhaust the cooling air to the cooling air source such that the flowpath defines a closed loop within the compressor.

A method for pressure and temperature control of fluid in a series of cryogenic compressors. An actual speed for each compressor and an actual inlet pressure and actual inlet temperature at entry are determined. The maximum speed for each compressor and a desired inlet pressure for the first compressor is provided. A speed index for each compressor is determined from the maximum speed and actual speed of each compressor. A proportional value is determined from the deviation of the actual and desired inlet pressure. A priority value is determined from the smaller of the proportional value and the smallest speed index. A desired inlet temperature for the first compressor and a desired speed for each compressor are determined from the priority value. The actual inlet temperature is adjusted to the determined desired inlet temperature and the actual speed for each compressor is adjusted to the determined desired speed.

A turbo-molecular pump comprises: a rotor having a plurality of stages of rotor blades and a cylindrical section; a plurality of stages of stationary blades alternately arranged with respect to the rotor blades; a stator arranged with a gap from the cylindrical section, the stator together with the cylindrical section constituting a screw groove pump section; a plurality of spacers stacked on a base, the spacers including at least one cooling spacer having a cooling section; a heater heating the stator; a temperature regulation section controlling the heater to regulate the temperature of the stator so as to be a reaction product accumulation prevention temperature; and an auxiliary ring for reaction product accumulation prevention at least a part of which is located in a space between the spacer facing a bottom step rotor blade, and the bottom step rotor blade.

Systems and methods for reducing the pressure of a first pressurized fluid, thereby reducing the temperature of the pressurized fluid, and utilization of the reduced-pressure and temperature fluid to cool a second fluid. Such an approach can enable a reduction in the size and weight of a hydraulic system, utilize waste energy in a system, and/or minimize electrical power requirements of a system, among other benefits.

A centrifugal fan including first blades and second blades disposed at both sides of a main plate, respectively, and a first convex part and a second convex part formed at a fan housing to correspond to the first blades and the second blades, respectively, wherein an airflow generated by the first blades and an airflow generated by the second blades are guided to be divided into the first convex part and the second convex part, respectively.

A centrifugal blower and heating element apparatus includes a base, a scroll housing having primary and secondary inlet ports, and an integrated heating element, motor and impeller. The apparatus may be provided as a portable appliance used for heating a room. The apparatus may have an elongated aspect ratio and a space efficient design.

An air blower including a convex part protruding away from the rotation axis of an impeller. When arbitrary cross-sectional surfaces are provided by cutting the convex part in a parallel direction with the rotation axis, each point of the inner circumferential surface of the convex part, which has a maximum distance from the rotation axis, leans toward a first plate of the first and second plates, at which inlets are formed.