Process for producing a high and low pressure integrated turbine rotor
US6569269B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2000 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Nov 14, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01D5/28
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In CrMoV based heat resistant steels and tungsten-containing CrMoV based heat resistant steels, trace impurities, such as phosphorus, sulfur, copper, aluminum, arsenic, tin, and antimony are reduced lower than a specific level. Furthermore, alloy steels having increased creep strengths in a creep test on an unnotched test piece by addition of trace impurities such as cobalt, tantalum, nitrogen, boron, or the like is used. The production process therefor includes heating a turbine rotor member having the specific composition at a temperature between 980° C. and 1100° C. at a part corresponding to the high-pressure part thereof and at a temperature between 850° C. and 980° C. at a part corresponding to the low-pressure part thereof, and cooling the turbine rotor member at a cooling rate higher than an air impact cooling rate at the part corresponding to the high-pressure part thereof, and at a cooling rate no lower than an oil quenching rate at the part corresponding to the low-pressure part thereof. The rotor member has a creep rupture time in a creep test on a notched test piece of 10000 hours or longer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.