METHOD TO PROVIDE SERVEABILITY OF BLADE OF GAS-TURBINE ENGINE Russian patent published in 2008 - IPC F01D5/10 

FIELD: aircraft industry: gas-turbine engines.

SUBSTANCE: invention relates to methods providing serviceability of blades of rotors of gas-turbine engines at vibration. According to proposed method, finishing of initially made blade by damping of vibrations owing to friction between longitudinal parts is carried out to increase safety margin of blade to resist variable stresses. Thanks to it, serviceability of initially manufactured blade is provided, and there is no need to design and manufacture of new blade, which cuts down labor input and cost of finishing. Moreover, as additional result, nonbreakability of engine body at smaller thickness is provided and unbalancing of rotor is prevented. To provide serviceability of blade of gas-turbine engine, vibration strength characteristics of blade according to variable stresses in solid blade are determined and compared with tolerable ones, and if obtained characteristics exceed tolerable values, blade is subjected to finishing. Novelty, according to proposed method, is that finishing is carried out with division of blade in longitudinal direction into parts, and place of division is determined to provide difference in natural frequencies of blade parts and then parts of blade are brought to contact along division plane with provision of friction in between. To improve efficiency of vibration damping, division is made along wave-shaped or zigzag surfaces. To prevent wearing out of mating surfaces of blade parts, wear resistant coating is applied to said surfaces. Two prevent separation of joint and to preserve aerodynamic profile of blade, groove is made on blade surface at both sides of division plane which is filled up with material whose modulus of elasticity is other than that of modulus of elasticity of blade material, for instance, with elastomer.

EFFECT: improved serviceability of initially made blade, reduced labor input for designing and manufacture of new blade and cost of finishing.

6 cl, 6 dwg