Finite Element Analysis Of The Thermal Characteristics Of High-speed Electric Spindle

High-speed machining is a promising advanced manufacturing technology for increasing productivity and reducing production costs dramatically. High-speed machine tool is the precondition for realizing high-speed machining. High-speed motorized spindle technology is of great significance to the research and development of high-speed machine tool. Compared with conventional spindle, motorized spindle is equipped with a built-in motor, so that power transmission devices such as gears and belts are eliminated and "zero transmission" is realized. However, lack of a complete understanding of thermal properties severely limits the effective application of high-speed spindle. High-speed spindle is notorious for its sudden catastrophic failures even without alarming signs at high speed due to thermal problems. The heat generated due to loss in the built-in motor and friction in the bearings is significant during high speed machining and the thermal deformations of the spindle decrease the accuracy of high-speed machine tool greatly. The thermal analysis of the high-speed spindle is necessary in order to reduce temperature-rise and thermal deformations. In this paper, the heat generation developed in the built-in motor and the bearings is calculated. The analysis of the oil-water heat change system and the oil-air lubrication system is also done. The motorized spindle is modeled and its thermal characteristics analysis by finite element method is also done using ANSYS software. And the main measures to improve thermal characteristics of the high-speed motorized spindle are brought forward.