Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which includes a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium so that a second lubrication oil enriched operating medium is provided by the oil separator, the provided second operating medium having at least in a second operating state a viscosity ratio of ?>1.

Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which provides a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium to a value between 25% by weight and 80% by weight.

Abstract: A hybrid roller bearing having an inner raceway and an outer raceway and a plurality of rollers arranged therebetween. The inner raceway and the outer raceway are made from bearing steel and have a first surface RMS roughness Rq1. At least one roller is made from a ceramic material and has at least at the roller raceway a second surface RMS roughness Rq2. The roughness of the raceways Rq1 is 1.2 to 4 times higher than the roughness Rq2 of the at least one roller, as well as a refrigerant compressor with such a hybrid roller bearing.

Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which provides a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium to a value between 15% by weight and 50% by weight.

Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which provides a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium to a value between 25% by weight and 80% by weight.

Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which provides a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium to a value between 15% by weight and 60% by weight.

Abstract: A cooling system includes a refrigerant compressor and a first operating medium, which includes a mixture of refrigerant and lubrication oil. An oil separator reduces the percentage of the refrigerant in the operating medium so that a second lubrication oil enriched operating medium is provided by the oil separator, the provided second operating medium having at least in a second operating state a viscosity ratio of K>1.

Abstract: A lubricant supply system includes a tank defining an internal volume. A divider is positioned within the tank that separates the internal volume into a first portion and a second portion. A first pump is in fluid communication with the first portion of the internal volume and configured to introduce a liquid refrigerant into the first portion of the internal volume.

Abstract: A lubricant supply system includes a tank defining an internal volume. A divider is positioned within the tank that separates the internal volume into a first portion and a second portion. A first pump is in fluid communication with the first portion of the internal volume and configured to introduce a liquid refrigerant into the first portion of the internal volume.

Abstract: A lubricant supply system includes first and second tanks, each including an internal volume that is divided into a first portion and a second portion. The first portion of the internal volume of the first tank and the first portion of the internal volume of the second tank are configured to alternate supplying a liquid refrigerant to a machine. A pump is in fluid communication with the second portion of the internal volume of the first tank and the second portion of the internal volume of the second tank. The pump is configured to vary a pressure of a gas in the second portion of the internal volume of the first tank and the second portion of the internal volume of the second tank.

Abstract: A method for lubricating a rolling element bearing by an ultra low viscosity volatile fluid comprises injecting a liquefied fluid flow into the bearing, lubricating rolling contacts between the rings and the rolling elements of the bearing by the liquefied fluid, providing a flow restriction for the liquefied fluid so as to maintain at least part of the fluid at a pressure which is above the evaporation pressure which is defined by evaporation of the fluid at the temperature or temperatures which prevail(s) in the bearing.

Abstract: A method for lubricating a rolling element bearing by an ultra low viscosity volatile fluid comprises injecting a liquefied fluid flow into the bearing, lubricating rolling contacts between the rings and the rolling elements of the bearing by the liquefied fluid, providing a flow restriction for the liquefied fluid so as to maintain at least part of the fluid at a pressure which is above the evaporation pressure which is defined by evaporation of the fluid at the temperature or temperatures which prevail(s) in the bearing.

Abstract: Rolling bearing comprising at least one ring with raceway and rolling elements. To increase resistance against failure in an environment containing hydrogen disulphide the related part of the rolling bearing is coated with a nickel-phosphorus coating.

Abstract: A screw compressor assembly, comprising a housing, a pair of rotors rotatably journaled in said housing, a bearing system supporting the rotors including a radial cylindrical roller bearing and thrust bearing means rotatably supporting the journals in the housing including a first angular contact thrust ball bearing having a predetermined contact angle in the range of between about 30.degree. and 35.degree., and a second back-up angular contact bearing having a contact angle less than said contact angle of said first thrust bearing and in the range of between about 15.degree. and 20.degree., the difference between the contact angles of the thrust bearing and backup bearing being at least between about 10.degree. and 20.degree. whereby the internal force due to centrifugal force is small and therefore the induced axial force in the bearing system is minimized.