Recommended Specifications for Speed-Governing of Steam Turbines Intended to Drive Electric Generators Rated 500 Kw and Larger Aiee-Asme Committee Report

The formation of a joint AIEE-ASME committee for the purpose of preparing a recommended specification covering the speed-governing of prime movers intended to drive electric generators that may, if desired, be included in prime-mover purchase specifications, was approved by the AIEE Board of Directors on January 30, 1941 and by the ASME Council on June 15, 1941. The personnel of this Joint Committee was appointed jointly by the chairmen of the AIEE Power Generation Committee and the ASME Standing Committee on Power Test Codes under sponsorship of the ASME Power Division. The work of the joint committee resulted in the issuance in 1949 of a recommended specification covering speed-governing of steam turbines intended to drive electric generators rated 500 kw and up.1 The joint committee was reorganized in 1955 and instructed to prepare a revision of the recommended specification. This revision, like the original, is limited in its scope to steam turbine-generators rated 500 kw and larger. Specifications for other types of prime movers will be issued, upon completion, as separate publications. This recommended specification does not cover emergency governors or other overspeed control devices, and in general, devices which are not responsive to speed. Exceptions to the latter were made for turbines designed to operate with controlled steam pressures, as in the case of turbines with initial and/or exhaust steam pressure control, automatic-extraction and mixed-pressure turbines, since the performance of the speed-governing system is affected by the performance of the steam pressure-regulating system.