METHOD OF CHECK OF COOLED WALL HAVING HOLES Russian patent published in 1998 - IPC

FIELD: power-plant engineering and aircraft engine manufacture. SUBSTANCE: method consists in blowing the wall which is in contact with melt of solidifying metal with gas whose temperature is below solidification temperature of melt. Simultaneously air is blown in gas flow and local thicknesses of rim on surface of metal are measured. Contact with melt of solidifying metal is effected on the outside of the wall; temperature of air being blown-in is maintained above temperature of main flow of gas but below or equal to solidification temperature of melt. Efficiency of cooling is judged from heat-transfer coefficient found from the following formula: , where is intensity of release of latent heat of solidification of metal; L′ is volumetric heat of solidification of metal; τ is time of solidification of rim of metal on surface of part; T_cr is solidification temperature of metal; Tvxm.p.

is temperature of gas blown at point of injection; G_m.p. is flow rate of gas being blown-in; C_p.m.p. is specific heat of gas being blown in; F is area of section of surface of part where α_m.p. is determined; δ_r is thickness of rim; δ_m.p. is thickness of rim solidified on surface of part with no thermal interaction with flow of gas being blown in; δ_r.main-δ_r; δ_r.main R_ct is thermal resistance of part. EFFECT: enhanced accuracy and reduced labour consumption. 1 dwg