This application claims the priority of International Application No. PCT/DE2004/002571, filed Nov. 20, 2004, and German Patent Document No. 103 58 421.8, filed Dec. 13, 2003, the disclosures of which are expressly incorporated by reference herein.
The invention relates to a rotor for a turbo engine, in particular a gas turbine.
According to the state of the art, a distinction is made in principle between two types of rotors for a turbo engine, namely so-called integrally bladed rotors and rotors in which the blades are inserted, i.e., anchored, in a rotor base body by a footing.
Integrally bladed rotors are referred to either as BLISK (bladed disk) or BLING (bladed ring), depending on whether the rotor base body is disk-shaped or ring-shaped. In such integrally bladed rotors, the rotor blades are fixedly connected to the ring-shaped or disk-shaped rotor base body and thus form an integral part of the rotor base body. Production of such integrally bladed rotors is complex and may be performed, for example, by milling from a solid on a 5-axis milling machine. One disadvantage of integrally bladed rotors in a BLING or BLISK design is the poor possibility of repairing them.
Rotors in which the rotor blades are inserted into the rotor base body via footing are easier to manufacture and repair than integrally bladed rotors but they are much heavier than integrally bladed rotors because the connection of the rotor blades to the rotor base body by way of the blade footing is under high stresses due to centrifugal forces and therefore must be designed with a reliable construction. In the related art, the rotor base body is designed in the shape of a disk in rotor designs in which the rotor blades are anchored in the rotor base body via the footing. The disk-shaped design of the rotor base body and the connection of the rotor blades to the rotor base body via suitably dimensioned blade feet results in a heavy weight of the rotor, which is a disadvantage of this design principle.
Against this background, the object of the present invention is to propose a novel rotor for a turbo engine, in particular for a gas turbine.
According to this invention, the rotor base body is formed by at least one ring-shaped element made of a metal matrix composite material (MMC material), where the rotor blades are attached to the rotor base body by footing so that the footing is positioned in a fiber-free area of the rotor base body.
In the sense of the present invention, a rotor for a turbo engine is proposed, preferably having a low weight on the one hand while being easy to manufacture and repair on the other hand. Thus, in the sense of the present invention, the rotor base body is formed from at least one ring-shaped element made of a metal matrix composite material. The design of the rotor base body has at least one ring-shaped element and, manufacturing it by the MMC technology, allows a definite weight reduction in comparison with the rotors known from the related art. In addition, individual rotor blades can be replaced easily when repairing the rotor.
According to an advantageous refinement of the present invention, the rotor base body is comprised of two ring-shaped elements made of a metal matrix composite material (MMC material), the rotor blades being attached between the two ring-shaped elements on the outer end radially. Blade feet of the rotor blades engage in a corresponding recess, i.e., indentation in the area of the ring-shaped elements, namely between fiber-reinforced areas of the two ring-shaped elements. Each rotor blade is preferably positioned with one platform each between peripheral protrusions of the two ring-shaped elements that are on the outside radially, with the ends of the platforms being in contact with the peripheral protrusions.
According to an alternative advantageous embodiment of the present invention, the rotor base body is formed by a ring-shaped element made of a metal matrix composite material (MMC material), sections of the ring-shaped element on the outside axially being fiber-reinforced and a section in between being designed to be fiber-free, with the blade footing of the rotor blades being secured in the fiber-free section. Boreholes running radially are preferably created in the fiber-free section of the ring-shaped element, each rotor blade being anchored by footing in a borehole.
Exemplary embodiments of the present invention are explained in greater detail on the basis of the drawings, without being limited thereto. They show:
The present invention is described in greater detail below with reference to
The rotor 10 according to
In the exemplary embodiment according to
The rotor blades 12 are mounted on the outer end radially of the rotor base body 12 between the two ring-shaped elements 13 and 14, each rotor blade 12 being positioned with a footing 18 between the fiber-reinforced areas 16 and 17 of the two ring-shaped elements 13 and 14. As shown in
As can be seen in
The two ring-shaped elements 13 and 14 of the rotor base body 11 are joined together on the sections 22 and/or 23 that are on the inside radially. The sections 22 and 23 on the inside radially, where the ring-shaped elements 13 and 14 are joined together, are designed to be fiber-free. Several boreholes 24 distributed over the circumference are introduced into these sections 22 and 23 that are on the inside radially. For detachable connection of the two ring-shaped elements 13 and 14, bolt-like screw connectors 25 engage in these boreholes 24. Thus, the two ring-shaped elements 13 and 14 of the rotor base body 11 are securely held together by the screw connectors 25 and the rotor blades 12 are securely anchored by their footing 18 in the corresponding recesses 19 in the ring-shaped elements 13 and 14. The exemplary embodiment illustrated in
The ring-shaped element 29 of the exemplary embodiment of
As
Rotor blades 36 inserted into the boreholes 35 are held in this position by a retaining ring (not shown). The retaining ring that is not shown is in contact with the radially inside end of the boreholes 35 over the entire circumference of the ring-shaped element 29, pressing radially outward so that the rotor blades 28 are rigidly connected to the ring-shaped element 29 in an airtight connection. To increase the strength of the ring-shaped element 29, the high-tensile fibers 32 may be wrapped around the boreholes 35 in a sinusoidal or cosinusoidal form in the area of the boreholes 35.
These two exemplary embodiments having in common the fact that at least one ring-shaped element made of a metal matrix composite material is used as the rotor base body. The ring-shaped element or each ring-shaped element of the rotor base body has at least one fiber-reinforced section and/or area and at least one fiber-free area, with the footing of the rotor blades running in the fiber-free area of the ring-shaped element or each ring-shaped element. A definite weight reduction for rotors of a turbo engine can be achieved with such a design. Furthermore, such rotors are easy to manufacture and repair.
Number | Date | Country | Kind |
---|---|---|---|
103 58 421 | Dec 2003 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/DE2004/002571 | 11/20/2004 | WO | 00 | 7/6/2007 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2005/056983 | 6/23/2005 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
1325208 | Rice | Dec 1919 | A |
1470499 | Steenstrup | Oct 1923 | A |
2264877 | Hezekiah | Dec 1941 | A |
2494658 | Highberg et al. | Jan 1950 | A |
2988324 | Sutters | Jun 1961 | A |
3532438 | Freyman et al. | Oct 1970 | A |
3625634 | Stedfeld | Dec 1971 | A |
4339229 | Rossman | Jul 1982 | A |
4397609 | Kochendorfer | Aug 1983 | A |
4684325 | Arnold | Aug 1987 | A |
4743166 | Elston et al. | May 1988 | A |
5061152 | Marey | Oct 1991 | A |
5263823 | Cabaret et al. | Nov 1993 | A |
5332360 | Correia et al. | Jul 1994 | A |
5421703 | Payling | Jun 1995 | A |
5474419 | Reluzco et al. | Dec 1995 | A |
5797725 | Rhodes | Aug 1998 | A |
5941688 | Dambrine | Aug 1999 | A |
6086327 | Mack et al. | Jul 2000 | A |
6790000 | Wolf | Sep 2004 | B2 |
Number | Date | Country |
---|---|---|
497 641 | Oct 1970 | CH |
2 027 861 | Dec 1971 | DE |
101 63 951 | Dec 2002 | DE |
1266976 | Mar 1972 | GB |
Number | Date | Country | |
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20080025844 A1 | Jan 2008 | US |