Abstract: An absorber tube is provided that includes a metal tube, a glass sleeve tube surrounding the metal tube, and a glass-metal transition element is disposed on at least one end. The metal tube and the transition element can be moved relative to one another in the longitudinal direction and connected to one another by an expansion compensating device. An inner end of the expansion compensating device is fastened to an attachment element, which is connected to the transition element. An outer end of the expansion compensating device is fastened to the metal tube. An annular space section of the annular space is constructed between the transition and attachment elements. The attachment element has an annular disc on which the expansion compensating device is fastened. The absorber tube has at least one shielding device that has a first annular disc-shaped section disposed on at least one end in the annular space.

Abstract: An absorber tube is provided that has a central metal tube, a glass cladding tube, and a glass-metal transition element. The metal tube and the glass-metal transition element are connected to each other by an expansion compensation device such that they can be displaced relative to each other in the longitudinal direction. The expansion compensation device is arranged at least partially in an annular space between the metal tube and the glass-metal transition element. In the annular space, at least one shielding device is arranged, which has a first annular disc-shaped segment arranged at an axial distance in front of the end face and covers at least the connection region of the attachment element and the inner end of the expansion compensation device.

Abstract: An absorber tube is provided that includes a metal tube, a glass sleeve tube surrounding the metal tube, and a glass-metal transition element is disposed on at least one end. The metal tube and the transition element can be moved relative to one another in the longitudinal direction and connected to one another by an expansion compensating device. An inner end of the expansion compensating device is fastened to an attachment element, which is connected to the transition element. An outer end of the expansion compensating device is fastened to the metal tube. An annular space section of the annular space is constructed between the transition and attachment elements. The attachment element has an annular disc on which the expansion compensating device is fastened. The absorber tube has at least one shielding device that has a first annular disc-shaped section disposed on at least one end in the annular space.

Abstract: An absorber tube is provided that has a central metal tube, a glass cladding tube, and a glass-metal transition element. The metal tube and the glass-metal transition element are connected to each other by an expansion compensation device such that they can be displaced relative to each other in the longitudinal direction. The expansion compensation device is arranged at least partially in an annular space between the metal tube and the glass-metal transition element. In the annular space, at least one shielding device is arranged, which has a first annular disc-shaped segment arranged at an axial distance in front of the end face and covers at least the connection region of the attachment element and the inner end of the expansion compensation device.

Abstract: The tubular radiation absorbing device (1) for solar thermal applications has a central tube (2) and a glass tubular jacket (3) surrounding the central tube (2) so that a ring-shaped space (4) is formed between the central tube (2) and the tubular jacket (3). The ring-shaped space (4) contains at least one inert gas with a partial pressure of 3 to 200 mbar. Alternatively in another embodiment a gas-tight closed container (10) filled with at least one inert gas is arranged in the ring-shaped space (4). The container (10) has a device for supplying inert gas to the ring-shaped space (4) in order to compensate for increased heat losses due to diffusion of hydrogen into the ring-shaped space (4) from the heat carrier medium.

Abstract: The method of making a vacuum tube collector or X-ray tube, which includes a matching glass-metal joint, includes providing a glass tube (1) made of a glass with a composition, in percent by weight on the basis of oxide content, consisting of B2O3, 8-11.5; Al2O3, 5-9; Na2O, 5-9; K2O, 0-5; CaO, 0.4-1.5; balance, SiO2; and bonding, preferably fusing or melting, an end portion of the glass tube (1) with a metal part (2) in order to bond or attach the glass tube to the metal part, thus forming a long-lasting glass-metal joint. The method of making the glass-metal joint is performed without using intermediary glass compositions of varying thermal conductivities. In the case of the vacuum tube collector the method can provide the basis for an automated manufacture of the vacuum tube collector.

Abstract: A tubular radiation absorbing device (1) designed for a solar heating application is described. The tubular radiation absorbing device has a metal central tube (3) and a glass tubular jacket (2) surrounding the central tube (3). A folding bellows (11) is connected between the central tube (3) and the tubular jacket (2), so that the tubular jacket and the central tube are movable relative to each other. A connecting element (20) connects an inner end of the folding bellows (11) with the central tube (3) and extends from the inner end of the folding bellows (11) through an inner annular space (30) between the folding bellows (11) and the central tube (3). The connecting element includes at least a part of a hydrogen window (50). A getter (6) is arranged in an outer annular space (33) between the folding bellows (11) and the tubular jacket (2).

Abstract: The tubular radiation absorbing device (1) for solar thermal applications has a central tube (2) and a glass tubular jacket (3) surrounding the central tube (2) so that a ring-shaped space (4) is formed between the central tube (2) and the tubular jacket (3). The ring-shaped space (4) contains at least one inert gas with a partial pressure of 3 to 200 mbar. Alternatively in another embodiment a gas-tight closed container (10) filled with at least one inert gas is arranged in the ring-shaped space (4). The container (10) has a device for supplying inert gas to the ring-shaped space (4) in order to compensate for increased heat losses due to diffusion of hydrogen into the ring-shaped space (4) from the heat carrier medium.

Abstract: The tubular radiation absorbing device (1) for solar thermal applications includes a central tube (3) made of chromium steel, particularly stainless steel; a glass tubular jacket (2) surrounding the central tube so as to form a ring-shaped space (6); and a barrier coating (4) on at least an interior side of the central tube (3), which is substantially impermeable to hydrogen and contains chromium oxide. The barrier coating (4) is provided by a process in which the central tube (3) is treated with steam containing free hydrogen at a temperature of 500° C. to 700° C.

Abstract: A tubular radiation absorbing device (1) designed for a solar heating application is described. The tubular radiation absorbing device has a metal central tube (3) and a glass tubular jacket (2) surrounding the central tube (3). A folding bellows (11) is connected between the central tube (3) and the tubular jacket (2), so that the tubular jacket and the central tube are movable relative to each other. A connecting element (20) connects an inner end of the folding bellows (11) with the central tube (3) and extends from the inner end of the folding bellows (11) through an inner annular space (30) between the folding bellows (11) and the central tube (3). The connecting element includes at least a part of a hydrogen window (50). A getter (6) is arranged in an outer annular space (33) between the folding bellows (11) and the tubular jacket (2).

Abstract: An arrangement to increase the thermal fatigue resistance of glass tubes having fluid flowing therethrough and being pressure-loaded. This arrangement comprises a glass tube, into which an interior component is inserted. The interior component can be designed as thin-walled tube or tubular component. In accordance with a first example the cavity enclosed by the interior component is hydraulically connected with the interior of the glass tube. The wall thickness of the interior component is smaller than the wall thickness of the glass tube and the interior component is partially free from a direct heat connection with the glass tube. In accordance with a second example the interior component increases the wall thickness of the glass tube. In this case the interior component is touching the interior circumference of the glass tube.

Abstract: A collector module (1) is described with a collector manifold (20) having two chambers. This collector module (1) has at least one collector tube (2), which has an absorber tube (4) and a tubular jacket (3). A connector (40) for each collector tube is provided which embraces the collector manifold (20) and receives the end of its tubular jacket (3). The connector (40) has a cup-shaped receiving part (41) glued on its collector tube and a U-shaped connecting part (45) formed on the cup-shaped receiving part (41), which engages the collector manifold (20). A sealing device (60) is arranged on the U-shaped connecting part (45). A torsion-stiff, self-supporting device is provided accordingly by this structure, in which each collector tube is not loaded with external forces, during to thermal expansion, transport, mounting or the like.

Abstract: The absorber pipe (1), especially for a parabolic collector for a solar heat collecting apparatus, is described. The absorber pipe (1) includes central metal pipe (3), a glass sleeve tube (2) surrounding the nine so that an annular space (4) is formed between them and an expansion compensating device connecting the central metal nine and a glass-metal transitional element (5) on a free end of the sleeve tube (2). The expansion compensation device (10) connects the metal pipe and sleeve tube, so that they can slide relative to each other, and includes folding bellows (11) for that purpose. Furthermore it also includes a connecting element (15), which has either a cylindrical or a conical section (17,18,18?) and which connects an interior end of the folding bellows with the metal pipe.

Abstract: The method of making a vacuum tube collector or X-ray tube, which includes a matching glass-metal joint, includes providing a glass tube (1) made of a glass with a composition, in percent by weight on the basis of oxide content, consisting of B2O3, 8-11.5; Al2O3, 5-9; Na2O, 5-9; K2O, 0-5; CaO, 0.4-1.5; balance, SiO2; and bonding, preferably fusing or melting, an end portion of the glass tube (1) with a metal part (2) in order to bond or attach the glass tube to the metal part, thus forming a long-lasting glass-metal joint. The method of making the glass-metal joint is performed without using intermediary glass compositions of varying thermal conductivities. In the case of the vacuum tube collector the method can provide the basis for an automated manufacture of the vacuum tube collector.

Abstract: The absorber pipe (1), especially for a parabolic collector for a solar heat collecting apparatus, is described. The absorber pipe (1) has a central metal pipe (3) and a glass sleeve tube (2). An expansion compensation device (10) is provided, which is arranged at least partially in an annular space (4) between the metal pipe (3) and a glass-metal transitional element (5), which is attached to the sleeve tube (2). The expansion compensation device (10) can have a folding bellows (11). Furthermore a connecting element (15) is provided, which has either a cylindrical or a conical section (17, 18, 18″).

Abstract: The invention relates to an arrangement (2; 2.2; 2.6; 2.7) to increase the thermal fatigue resistance of glass tubes (1; 1.2; 1.6; 1.7) flown through by fluid and pressure-loaded. This arrangement comprises a glass tube (1; 1.2; 1.6; 1.7), into which an interior component (3; 3.2; 3.6; 3.7) is inserted. The interior component (3; 3.2; 3.6; 3.7) can be designed as thin-walled tube (19; 19.2) or tubular component. In accordance with a first design example the cavity enclosed by the interior component (3; 3.2) is hydraulically connected with the interior (10) of the glass tube (1; 1.2). The wall thickness (s3) of the interior component (3; 3.2) is smaller than the wall thickness of the glass tube (1; 1.2) and the interior component (3; 3.2) is in the condition of being flown through by fluid at least partially free from a direct heat connection with the glass tube (1; 1.2). In accordance with a second design example the interior component (3.6; 3.7) increases the wall thickness of the glass tube (1.6; 1.7).

Abstract: A collector module (1) is described with a collector manifold (20) having two chambers. This collector module (1) has at least one collector tube (2), which has an absorber tube (4) and a tubular jacket (3). A connector (40) for each collector tube is provided which embraces the collector manifold (20) and receives the end of its tubular jacket (3). The connector (40) has a cup-shaped receiving part (41) glued on its collector tube and a U-shaped connecting part (45) formed on the cup-shaped receiving part (41), which engages the collector manifold (20). A sealing device (60) is arranged on the U-shaped connecting part (45). A torsion-stiff, self-supporting device is provided accordingly by this structure, in which each collector tube is not loaded with external forces, during to thermal expansion, transport, mounting or the like.