METHOD FOR DETERMINING THE REMAINING SERVICE LIFE OF A ROTOR OF A THERMALLY LOADED TURBOENGINE

• US 20100296918A1
• Filed: 04/23/2010
• Published: 11/25/2010
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: RUFFINO, Paolo, CONGIU, Francesco, MOHR, Wolfgang Franz Dietrich, WEISS, Peter, EHRSAM, Andreas
• Granted Patent: US 8,454,297 B2
• Time in Patent Office: Days
• US Class Current: 415/118
• CPC Class Codes: F01D 17/085 to temperature
• CPC Class Codes: F01D 21/003 Arrangements for testing or measuring for measuring vibrations G01H
• CPC Class Codes: F01D 21/14 responsive to other specific conditions
• CPC Class Codes: F05D 2220/31 in steam turbines
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F05D 2270/114 by limiting mechanical stresses
• CPC Class Codes: F05D 2270/303 Temperature

Abstract

A method is provided for determining the remaining service life of a rotor of a thermally loaded turboengine. In the method, a temperature on the rotor is determined, the thermal stress on the rotor is derived from the determined temperature, and the remaining service life of the rotor is deduced from the derived thermal stress. A simple, exact and flexible determination of the remaining service life is achieved in that the temperature is measured directly at a predetermined point of the rotor, and in that the thermal stress on the rotor is derived from the measured temperature.

Claims

1. A method for determining the remaining service life of a rotor (11) of a thermally loaded turboengine (10), comprising:

determining a temperature on the rotor (11) of the turbine;

deriving a thermal stress on the rotor (11) from the determined temperature; and

deducing the remaining service life of the rotor (11) from the derived thermal stress, wherein the temperature is measured directly at a predetermined point (18) of the rotor (11), and the thermal stress on the rotor (11) is derived from the measured temperature.

2. The method as claimed in claim 1, wherein the turboengine is a steam turbine.

3. The method as claimed in claim 1, wherein the measurement of the temperature on the rotor (11) takes place contactlessly.

4. The method as claimed in claim 3, wherein the measurement of the temperature on the rotor (11) is carried out by a pyrometer (20).

5. The method as claimed in claim 1, wherein the rotor (11) is mounted rotatably about an axis (22) and is surrounded by a casing (13), in that rows of moving blades (17), through which hot working gas flows in the axial direction, are arranged on the rotor (11) one behind the other in the axial direction, the working gas is introduced into the blading (17) of the rotor (11) in an inlet region (14, 15), and the temperature on the rotor (11) is measured in the inlet region (14, 15).

6. The method as claimed in claim 5, wherein the inlet region is formed by an inflow spiral (14), formed in the casing (13) and surrounding the axis (22) annularly, for the radial introduction of the working gas and by a deflection duct (15), adjoining the inflow spiral (14), for deflecting the entering working gas from the radial direction to the axial direction, and the temperature on the rotor (11) is measured in the deflection duct (15) shortly before the start of the blading (17).

7. The method as claimed in claim 1, wherein the measurement of the temperature of the rotor (11) takes place from a fixed point on the surrounding casing (13).

8. The method as claimed in claim 7, wherein the measurement of the temperature of the rotor (11) takes place directly from a point on the surrounding casing (13) which lies opposite in the working gas duct (26).

9. An arrangement for carrying out the method as claimed in claim 1 in a thermally highly loaded turboengine or steam turbine (10) which comprises a rotor (11) mounted rotatably about an axis (22) having a blading (17) extending in the axial direction and which is surrounded by a casing (13) so as to form a hot working gas duct or hot steam duct (26), wherein a contactlessly operating temperature recorder (20) which records the temperature at the predetermined point (18) of the rotor (11) is arranged on the casing (13).

10. The arrangement as claimed in claim 9, wherein the temperature recorder is a pyrometer (20).

11. The arrangement as claimed in claim 9, wherein the turboengine or steam turbine (10) comprises an inlet region (14, 15) for introducing the working gas or hot steam into the blading (17) of the rotor (11), and the pyrometer (20) is oriented onto a measuring zone (18) of the rotor (11), said measuring zone lying in the inlet region (14, 15).

12. The arrangement as claimed in claim 9, wherein the temperature recorder (20) is arranged directly opposite the predetermined point or measuring zone (18) of the rotor (11) on the casing (13).

13. The arrangement as claimed in claim 9, wherein the temperature recorder (20) is arranged fixedly on the casing (13).

14. The arrangement as claimed in claim 9, wherein the temperature recorder (20) is connected to an evaluation unit (23).

15. The arrangement as claimed in claim 14, wherein the evaluation unit (23) is followed by an indicator device (24) for indicating the remaining service life.

16. The arrangement as claimed in claim 14, wherein the evaluation unit (23) has a control output (25) for controlling the operation of the turboengine or steam turbine (10).