Abstract: Fluid-injected screw-type compressor element comprising two co-operating rotors (2 and 3) which are radially and axially bearing-mounted in a housing (1), whereby this housing confines a rotor chamber (4) in which the rotors (2 and 3) are situated and in which a fluid circuit (11) for the injection of a fluid discharges, characterized in that the radial bearing of at least one rotor is formed by the contact of the rotor concerned with the part of the wall of the housing opposite the radial perimeter of the rotor concerned and/or the co-operation with the other rotor and by maximally one additional radial bearing.

Abstract: An improved multi-stage compressor device for compressing gas, which compressor device (1) mainly consists of at least two compressor elements (2-5-28) placed in series one after the other, at least one of which (5-28) is driven by a motor (9), characterized in that at least one other compressor element (2) is driven separately, in other words without any mechanical link with said motor (9), by means of an expander (18) of a closed power cycle (12) with a circulating medium inside which is heated by the compressed gas.

Abstract: Fluid-injected screw-type compressor element comprising two co-operating rotors (2 and 3) which are radially and axially bearing-mounted in a housing (1), whereby this housing confines a rotor chamber (4) in which the rotors (2 and 3) are situated and in which a fluid circuit (11) for the injection of a fluid discharges, characterised in that the radial bearing of at least one rotor is formed by the contact of the rotor concerned with the part of the wall of the housing opposite the radial perimeter of the rotor concerned and/or the co-operation with the other rotor and by maximally one additional radial bearing.

Abstract: An improved multi-stage compressor device for compressing gas, which compressor device (1) mainly consists of at least two compressor elements (2-5-28) placed in series one after the other, at least one of which (5-28) is driven by a motor (9), characterized in that at least one other compressor element (2) is driven separately, in other words without any mechanical link with said motor (9), by means of an expander (18) of a closed power cycle (12) with a circulating medium inside which is heated by the compressed gas.