One embodiment of a method for operating an internal combustion engine under a pressure less than atmospheric pressure includes the steps of positioning a vacuum pump such that said vacuum pump is in fluid communication with a crankcase of said internal combustion engine, connecting a discharge of said vacuum pump to a separator, wherein a portion of said discharge of said vacuum pump condenses in said separator, connecting a vapor discharge of said separator to a filter, wherein said filter removes a portion of volatile organic compounds from said vapor discharge, and venting said filter to an ambient atmosphere.

Progressing cavity devices and systems are provided. In one embodiment, a stator of a progressing cavity device includes metal plates with apertures that are rotationally offset to form a winding rotor conduit for receiving a rotor of the progressing cavity device. A layer of elastomer can be provided on edges of the apertures of the metal plates in the winding rotor conduit, and the stator can also include a gas breakout port through the metal plates to enable gas between the metal plates to escape the stator. Additional systems, devices, and methods are also disclosed.

A screw compressor for a utility vehicle includes at least one housing, at least one housing cover and at least one rotor housing. At least one seal is provided, wherein, when assembled, there is an oil sump in the housing, and the seal is arranged between the housing cover and the rotor housing and projects out of the oil sump with respect to the assembled state. The seal is formed as a sealing plate and has multiple passage openings.

A fluid transfer pump assembly is provided that includes an electronic device enclosure, a bore, and a vent pin. The electronic device enclosure includes a wall separating an interior from an exterior of the explosion-proof fluid transfer pump assembly. The electronic device enclosure includes a bore extending through the wall of the electronic device enclosure from the interior of the electronic device enclosure to the exterior of the explosion-proof fluid transfer pump assembly. The bore is formed by at least one peripheral surface extending from the interior of the electronic device enclosure to the exterior of the explosion-proof fluid transfer pump assembly. The vent pin extends into the bore. The vent pin fills space within the bore and engages the at least one peripheral surface except that at least one portion of a pin surface of the vent pin is spaced apart from at least one portion of the at least one peripheral surface of the bore.

A device for measuring flow processes of fluids. The device includes an inlet, an outlet, a drive unit, a positive displacement flow meter which is driven by the drive unit, the positive displacement flow meter including a positive displacement chamber, a supply duct which fluidically connects the positive displacement chamber to the inlet, a discharge duct which fluidically connects the positive displacement chamber to the outlet, a bypass which bypasses the positive displacement flow meter, a differential pressure sensor arranged in the bypass, and an evaluation and control unit which provides a control of the positive displacement flow meter based on a differential pressure applied to the differential pressure sensor. The supply duct and the discharge duct each rise in a fluid flow direction.

A screw compressor for a utility vehicle includes at least one housing, at least one housing cover and at least one rotor housing. At least one seal is provided, wherein, when assembled, there is an oil sump in the housing, and the seal is arranged between the housing cover and the rotor housing and projects out of the oil sump with respect to the assembled state. The seal is formed as a sealing plate and has multiple passage openings.

A device for measuring flow processes of fluids. The device includes an inlet, an outlet, a drive unit, a positive displacement flow meter which is driven by the drive unit, the positive displacement flow meter including a positive displacement chamber, a supply duct which fluidically connects the positive displacement chamber to the inlet, a discharge duct which fluidically connects the positive displacement chamber to the outlet, a bypass which bypasses the positive displacement flow meter, a differential pressure sensor arranged in the bypass, and an evaluation and control unit which provides a control of the positive displacement flow meter based on a differential pressure applied to the differential pressure sensor. The supply duct and the discharge duct each rise in a fluid flow direction.

A vane pump includes a liner defining a cammed inner surface, a rotor rotatably disposed within the liner that has a plurality of vane slots, and a plurality of vanes slidably disposed within vane slots of the rotor and configured to extend away from the rotor and contact the cammed inner surface of the liner. The plurality of vanes include at least one sentinel vane that is configured to allow detection of wear on the sentinel vane.

The invention relates to a scroll compressor for compressing a fluid, comprising a compression section with an inlet for sucking the fluid into the compression section, an outlet for discharging the compressed fluid out of the compression section, a stationary disk having a stationary spiral, and an orbiting disk having an orbiting spiral. The orbiting disk is orbitable relative to the stationary disk to move the fluid from the inlet to the outlet and to compress it thereby. The scroll compressor comprises an oil separator for separating oil from the compressed fluid and a direct oil return for directly returning oil from the oil separator to the compression section, the direct oil return comprising at least one orifice opening. For enabling efficient operation, the direct oil return comprises an outgassing chamber arranged between the first flow valve and the orifice opening and a fluid return for returning fluid from the outgassing chamber to the compression section.

A vane pump includes a liner defining a cammed inner surface, a rotor rotatably disposed within the liner that has a plurality of vane slots, and a plurality of vanes slidably disposed within vane slots of the rotor and configured to extend away from the rotor and contact the cammed inner surface of the liner. The plurality of vanes include at least one sentinel vane that is configured to allow detection of wear on the sentinel vane.