In view of the complexity of heating and cooling in the shielded motor with built-in spiral tube heat transfer and the particularity of working conditions,with the help of finite element analysis software,the physical model of 3D temperature field of shielded motor was established,the distribution law of temperature field inside the motor and the flow state of cooling medium were revealed by simulation calculation,and the reason was analyzed.The results show that the peak temperature of the motor appears at the upper end of the stator windings and is 98.3 ℃.The insulation is tested at 180 ℃ and the temperature rise of each component does not exceed the temperature rise limit of its material.The motor is in a safe state under the rated thermal condition.The calculation results can provide reference for the cooling system design and temperature field calculation of the same type of shielded motor.