Analysis on Interference Fit Calculation Method of Built-up Rotors of Turbo Machinery

摘要

The built-up rotor is applied widely for its cheaper cost and reliability in turbo machinery. The strength calculation of the impeller is one of the important roles in the calculation of the built-up rotor. The interference fit between the shaft and the impeller is a very important factor for the calculation. The standard of the interference fit calculation bases on the theory that radial tensile stress equals zero between the impeller and shaft when the speed of the turbo machine attains loose speed. By analyzing the standard of the interference fit calculation, the supposition is not fit. It is also error that the moment between the impeller and shaft is ignored. With the development of the turbo machinery, the power transferred from the disc to shaft rises rapidly. The factors ignored in the past calculation becomes important. Base on the forgoing analysis and the calculation contrast with some working state, the interference fit calculation method used widely can improve. The reliability of the interference fit between the shaft and the disc can approach the fact.