Process for heating sleeve shaft through magnetic induction by large ring component

Abstract

The invention relates to a process for heating a sleeve through magnetic induction by a large ring component. Finish machining is conducted on the ring component until certain size of the ring component is reached before shrinkage fit. In order to avoid thermal consumption after heating and prevent the surface of a ring from being burned due to the fact of partial overheat, asbestos cloth is coated and surrounds the outer surface of the ring, induction coils are wound on the outer surface of the ring, the ring is lifted above a rotating shaft through a crane, and after the ring is heated, when the minimum size of the ring is detected to meet requirements of a drawing through a measuring bar, the ring is smoothly dropped, and the shrinkage fit is conducted on the ring. After the ring is cooled to room temperature, size difference of an outer ring of the ring before the shrinkage fit and after the shrinkage fit is not larger than 0.02 millimeter. After the shrinkage fit is finished for the first time, the ring does not need machining a large equipment for the second time again after the shrinkage fit, the lowest heating temperature is controlled through intermediate-frequency electromagnetic induction heating, and deformation of the ring is small after the shrinkage fit after the ring is heated. The process for heating the sleeve shaft through magnetic induction by the large ring component has the advantages of being simple in operation, simple in required equipment, low in manufacturing cost, short in working period and the like, can save a large amount of cost from secondary machining to large-equipment machining, and is very high in application value.

Description

technical field [0001] The invention relates to a process method for heating a sleeve shaft of a large circular ring component by magnetic induction. Background technique [0002] Sliding rotors and hub-type rotor brackets with fixed stator shafts for large hydro-generators generally adopt tight fits to transmit torque. In the past, the process method is to heat a single piece after rough machining and heat it up. This conventional method is difficult to control the temperature, most of which are above 300 degrees. Due to the high temperature during the heat sleeve, the shrinkage of the root of the shaft shoulder is relatively large during cooling and contraction, resulting in a large gap, which is unfavorable to the overall performance of the unit. Moreover, it takes too long to adjust and transport after heating, and the heat loss is serious. It is easy to get stuck during the heat-fitting process, and the heat-fitting requirements cannot be fulfilled. After the thermal ...

AI Technical Summary

Problems solved by technology

However, it is not suitable for thermal sleeve of components that cannot be heated by peripheral magnetic induction, such as radial rotor brackets with rotor arms.