Influence of tension and contact stress on sliding in cylindrical roller bearings in support of gas turbine engines

The tie between coefficient of slip and tight in a roller bearing 1032930 rotors of the turbine jet of PS-90 family with a rated mounting gap of 0,0425 mm is established. Tight in the bearing is defined in the estimated way depending on thermal deformations and inertial forces. Values of temperatures are taken from bench tests of the engine in case of rotational speeds from 9228 to 11308 RPM, the values of tight corresponding to them depend also on fit of an outside ring with the casing (the damping sleeve). In case of fit with tight in the bearing tight makes from 0,021 to 0,058 mm, in case of fit with a gap – from-0,0059 to 0,0478 mm. Owing to volume compressive stress of a shaft and stretching of the casing with a bearing outer ring of value of contact deformations and stress from tight considerably decrease, expressions for determination of each type of deformations are given. Stress of contact deformations is determined by a formula of Hertz and can change from 0 to 901 N/mm2 depending on rotational speed and fit of an outside ring with the casing. Curve dependences of values of tight, temperature, contact stress and coefficient of slip from rotational speed are constructed, so in case of tight from 0,0464 to 0,0558 mm and stress from tight of 659-895 N/mm2 the coefficient of slip makes about 2%. The valid stress in contact is unknown as conjugation of an outside ring to the casing has indefinite character, in case of the combined support the dispersion on deformation of a ring significantly will decrease that will lead to smaller dispersion on such indexes as coefficient of slip and longevity of the bearing.