Practical Experience with the Introduction of Honeycomb Shroud Seals on 250 – 800 MW Supercritical Pressure Units

Abstract

Practical experience with the introduction of honeycomb seals in the flow-through sections of 250 – 800 MW steam turbines with supercritical steam pressure is examined. The most widespread designs for shroud and end honeycomb seals used in the development of new turbine units are discussed, along with the modernization of existing steam turbine equipment. Test stand data on the relative flow rate and power characteristics of honeycomb, radial, and axial-radial seals are compared. Results are reported from thermal tests for evaluating the efficiency of installing honeycomb shroud seals in the high pressure cylinders of the T-250_300-240 turbine units at the TETs-21 plant of JSC “Mosenergo” and the K-800-240-5 turbine units at the Perm GRES plant of JSC “OGK-1.”