Abstract: In a method for fabricating a heat exchanger, a metal body includes a bore and inlet and outlet connectors fitted to the body at respective inlet and outlet ends of the bore. The connectors each include an inner surface in which annular grooves are formed. A tube is inserted in the bore such that inlet and outlet ends of the tube are respectively located in the inlet and outlet connectors. A mandrel is operated to expand at least a portion of the tube into contact with the body, and to expand the inlet and outlet tube ends into contact with the grooves of the inlet and outlet connectors, respectively. The heat exchanger provides improved thermal exchange efficiency between the tube and the body, and fluid-tight connections between the tube and the inlet and outlet connectors.

Abstract: A support for a rolling bearing of the kind equipped with an outer rotating ring for a rotary vacuum pump, the support comprising an inner portion that can be associated with the rotating ring, a fastening outer portion and a connecting portion, interposed between the inner and outer portions, wherein the connecting portion is a frusto-conical resilient element.

Abstract: A rotor assembly for rotary vacuum pumps has improved mechanical characteristics and low manufacturing cost due to a one-step thermal coupling of a rotor having a male axial projection and its supporting shaft having an end portion comprising a female cavity with a shape and size for receiving the male projection with interference at an ambient temperature. The rotor and the shaft are made of different materials. Heating of the end portion of the shaft provides expansion of the female cavity and allows for inserting the mail projection of the rotor into the female cavity of the shaft. By cooling the end portion to the ambient temperature the contraction of the cavity is obtained forming fixed interference coupling between the shaft and the rotor, where the end portion of the shaft contracts and compresses about the male axis projection of the rotor.

Abstract: In a method for fabricating a heat exchanger, a metal body includes a bore and inlet and outlet connectors fitted to the body at respective inlet and outlet ends of the bore. The connectors each include an inner surface in which annular grooves are formed. A tube is inserted in the bore such that inlet and outlet ends of the tube are respectively located in the inlet and outlet connectors. A mandrel is operated to expand at least a portion of the tube into contact with the body, and to expand the inlet and outlet tube ends into contact with the grooves of the inlet and outlet connectors, respectively. The heat exchanger provides improved thermal exchange efficiency between the tube and the body, and fluid-tight connections between the tube and the inlet and outlet connectors.

Abstract: A rotor assembly for rotary vacuum pumps has improved mechanical characteristics and low manufacturing cost due to a one-step thermal coupling of a rotor having a male axial projection and its supporting shaft having an end portion comprising a female cavity with a shape and size for receiving the male projection with interference at an ambient temperature. The rotor and the shaft are made of different materials. Heating of the end portion of the shaft provides expansion of the female cavity and allows for inserting the mail projection of the rotor into the female cavity of the shaft. By cooling the end portion to the ambient temperature the contraction of the cavity is obtained forming fixed interference coupling between the shaft and the rotor, where the end portion of the shaft contracts and compresses about the male axis projection of the rotor.

Abstract: A support for a rolling bearing of the kind equipped with an outer rotating ring for a rotary vacuum pump, the support comprising an inner portion that can be associated with the rotating ring, a fastening outer portion and a connecting portion, interposed between the inner and outer portions, wherein the connecting portion is a frusto-conical resilient element.