Abstract: A drive shaft system (100) comprising a shaft (80) connected to a motor via a coupling (50) and arranged to transmit a rotary movement from the motor to the rotor, at least two supports (65,75) arranged to position the shaft within a shaft housing (90), each support comprising at least one bearing (95,98), and at least one forcing element (135,145) arranged to force at least one of the supports against either an inner side of the shaft housing or an outer side of the shaft (80); such as to prevent turning and radial movements of the supports within the shaft housing while enabling axial movement of the shaft within the shaft housing. The bearings may be forced at either their inner or outer rings, and may be enclosed in a bearing housing (120) for protection and stiffness.

Abstract: An evaporator having an external vessel and an inner cavity, and a heat exchanging tube assembly, the external vessel comprising an opening closable by a hatch, the heat exchanging tube assembly being insertable into and removable from the inner cavity through the opening. In oil production and in other industrial processes, waste water is often produced which requires treatment. This water may be contaminated with amongst other contaminants Oil & Grease, minerals, Silica, and organic contamination.

Abstract: Locally backwashing portions of filter media allows a simple and effective design of intake and pretreatment units, as well as their integration. An enclosure is used to limit portions of filter media and backwash them locally by suction, utilizing filtered water from adjacent filter media as the back wash water. Wastewater is produced at small amounts that allows efficient sludge treatment. This design enables water pretreatment at the intake unit, simplifying overall plant design and preventing damage to organisms living outside the intake unit.

Abstract: A drive shaft system (100) comprising a shaft (80) connected to a motor via a coupling (50) 65 and arranged to transmit a rotary movement from the motor to the rotor, at least two supports (65,75) arranged to position the shaft within a shaft housing (90), each support comprising at least one bearing (95,98), and at least one forcing element (135,145) arranged to force at least one of the supports against either an inner side of the shaft housing or an outer side of the shaft (80); such as to prevent turning and radial movements of the supports within the shaft housing while enabling axial movement of the shaft within the shaft housing. The bearings may be forced at either their inner or outer rings, and may be enclosed in a bearing housing (120) for protection and stiffness.

Abstract: An evaporator having more efficient heat transfer tubes, that are either or both coated and vertically corrugated. The coating, though reducing the heat transfer co-efficient, lengthens the time between cleaning treatment to increase the overall efficiency of the evaporator. The corrugation of the tubes controls the film characteristics and enhances evaporation from the film upon condensation of vapor within the tubes. The corrugation profile is selected to enhance waviness and turbulence of the films and thereby increase evaporation and condensation and hence the effectivity of the evaporator.

Abstract: A rotor for mounting blades thereon to form an impeller rotatable about a main axis thereof. Each of the blades has a mounting portion. The rotor includes primary slots and auxiliary slots, each of the primary slots is adapted for receiving the mounting portion of the blade. The primary and auxiliary slots are adapted to change their dimensions during rotation of the impeller due to centrifugal forces and thermal effects caused by the rotation thereof. The change in dimensions is adapted to exert pressure on the mounting portion of the blade to retain it within the primary slot.

Abstract: According to the present invention there is provided a compact heat pump using water as refrigerant, comprising an evaporator located at a first end section of the heat pump casing, adapted to allow evaporation of water therefrom, One or more compressors located at a second end section of the heat pump casing adapted to induce said evaporation by maintaining vacuum, provided with an intake conduit extending from the evaporator to the compressor leading vapor thereto. A condenser is located in the intermediate section of the casing wherein the intake conduit passes therethrough, adapted for condensing the vapor. The heat pump also comprises vacuum means allowing creating and maintaining vacuum in the casing. There is also provided a snow dome allowing skiing and snow related activities in above zero conditions using the heat pump for creation of snow or ice slurry.

Abstract: Disclosed is a compact heat pump using water as refrigerant, including a casing having a first and second end sections and an intermediate section located therebetween, with an evaporator located at the first end section, configured for containing said water and allowing evaporation of at least a part of the water to produce vapor and remove heat from the remainder of the water. At least one agitator scoop is located within said evaporator, with one or more demisters installed between the evaporator and the compressor. The one or more compressors induce evaporation by maintaining vacuum at least at an intake conduit, and are configured for receiving the vapor through the intake conduit after passing through a heated demister. The condenser is configured for receiving the compressed vapor from the compressor, lowering the vapor temperature and condensing it back into a liquid state.

Abstract: According to the present invention there is provided a rotor (20) for mounting of a plurality of blades (30) thereon to form an impeller (10) rotatable about a main axis thereof. Each of the blades has a mounting portion (32). The rotor comprises primary slots (24) and auxiliary slots (26), each of the primary slots being adapted for receiving the mounting portion of the blade. The primary and auxiliary slots are adapted to change their dimensions during rotation of the impeller due to centrifugal forces and thermal effects caused by the rotation thereof.

Abstract: A piston for a linear spool valve, the valve comprising a body having a inner surface. The body is made of a material with a relatively low heat expansion coefficient ?1. The piston comprises a contact member having an outer surface and being adapted to reciprocate within the body of the valve so that the outer surface is in contact with the inner surface. The contact member has at least a first layer made of a material with a heat expansion coefficient ?2 essentially greater than ?1, i.e. ?2>>?1, and at least a second layer made of a material with a heat expansion coefficient ?3 close to ?1. This causes the contact member to be adapted to behave, along said outer surface, as a material having a heat expansion coefficient essentially closer to ?1 than to ?2. One of the layers constitutes an outer layer of the contact member and comprises the outer surface.

Abstract: A three-way two-position poppet valve (10) comprising a housing (12) with a generally cylindrical valve chamber (14), a first (20) and a second (16) port with coaxial 1 valve seats (26, 28) at the ends of the chamber, and a third lateral working port (18). A poppet body (36) is disposed reciprocably in the valve chamber so that in a first position of the poppet body the first valve seat (26) is sealed and the second port communicates with the working port, and in a second position the second valve seat (28) is sealed and the first port communicates with the working port. The valve is characterized in that the housing has two coaxial cylindrical passages (24, 30) adjacent the respective valve seats, while the poppet body has two coaxial cylinder parts (44, 48) slidingly and sealingly fitting the cylindrical passages, so that the poppet body is always supported in at least one of the cylindrical passages and fluid communication between the first and the second port is always prevented.

Abstract: A piston for a linear spool valve, the valve comprising a body having a inner surface. The body is made of a material with a relatively low heat expansion coefficient ?1. The piston comprises a contact member having an outer surface and being adapted to reciprocate within the body of the valve so that the outer surface is in contact with the inner surface. The contact member has at least a first layer made of a material with a heat expansion coefficient ?2 essentially greater than ?1, i.e. ?2>>?1, and at least a second layer made of a material with a heat expansion coefficient ?3 close to ?1. This causes the contact member to be adapted to behave, along said outer surface, as a material having a heat expansion coefficient essentially closer to ?1 than to ?2. One of the layers constitutes an outer layer of the contact member and comprises the outer surface.

Abstract: According to the present invention there is provided a compact heat pump using water as refrigerant, comprising an evaporator (20) located at a first end section of the heat pump casing (12), adapted to allow evaporation of water therefrom, One or more compressors (40) located at a second end section of the heat pump casing adapted to induce said evaporation by maintaining vacuum, provided with an intake conduit (32) extending from the evaporator (20) to the compressor (40) leading vapor thereto. A condenser (30) is located in the intermediate section of the casing (12) wherein the intake conduit (32) passes therethrough, adapted for condensing the vapor. The heat pump also comprises vacuum means (39) allowing creating and maintaining vacuum in the casing. There is also provided a snow dome allowing skiing and snow related activities in above zero conditions using the heat pump for creation of snow or ice slurry.

Abstract: A three-way two-position poppet valve (10) comprising a housing (12) with a generally cylindrical valve chamber (14), a first (20) and a second (16) port with coaxial 1 valve seats (26, 28) at the ends of the chamber, and a third lateral working port (18). A poppet body (36) is disposed reciprocably in the valve chamber so that in a first position of the poppet body the first valve seat (26) is sealed and the second port communicates with the working port, and in a second position the second valve seat (28) is sealed and the first port communicates with the working port. The valve is characterized in that the housing has two coaxial cylindrical passages (24, 30) adjacent the respective valve seats, while the poppet body has two coaxial cylinder parts (44, 48) slidingly and sealingly fitting the cylindrical passages, so that the poppet body is always supported in at least one of the cylindrical passages and fluid communication between the first and the second port is always prevented.

Abstract: A gasdynamic arrangement for a multi-stage centrifugal turbomachine, such as a two-stage compressor, comprising two coaxial impellers assembled on a common shaft with axial intake ports and radial peripheral discharge zones, the intake ports of the two impellers preferably pointing away from each other; a cylindrical vessel concentrically housing the impellers and the intake duct; a partition wall between the two impellers having a first and a second group of apertures; a first array of curved ducts conveying the flow from the first impeller discharge zone to the first group of apertures in the partition wall, the flow further passing through a chamber in the vessel to the intake port of the second impeller, and a second array of curved ducts conveying the flow from the second impeller discharge zone to the second group of apertures in the partition wall, the flow further going to the discharge port, the two flows bypassing each other in opposing directions at the partition wall.