METHOD OF HEAT INSULATION OF TURBINE BLADE (VERSIONS) AND DEVICE FOR OBTAINING BLADE PROFILE Russian patent published in 1997 - IPC

FIELD: power engineering. SUBSTANCE: method consists in manufacture of auxiliary envelope with chamber having shape of blade airfoil portion. Blank of ceramic coat is first applied on inner surface of auxiliary envelope which is then fitted on airfoil portion of blade. Envelope is fitted on surface of airfoil portion formed by helical motion of root section of airfoil portion also by helical motion. Template in form of airfoil portion is made and blank of coat is applied on surface of template. Material containing ceramic fibers is used as blank. Envelope may be fitted on airfoil portion at free clearance which is filled with binding agent and filler afterwards which makes it possible to restore used coat without removing it. Besides, heat-insulating coat may be made in the form of hose manufactured from fibrous ceramic material. Hose is stretched on air-foil portion of blade and is secured. Envelope is made from polymer or carbon material powder. Coat is applied when blade is in working position on rotor. Device for obtaining blade profile includes plunger for helical motion in radial direction. End of plunger carries grip with chamber widening towards rotor. Plunger is provided with longitudinal passage. EFFECT: enhanced efficiency. 20 cl, 14 dwg