Comparison of Motor Cooling System of Large Bulb Tubular Pump Unit

The three types of motor cooling system of large bulb tubular pump unit,open forced air-cooling and outer water-cooling,closed forced circular air-cooling and outer water-cooling and stator water-cooling and rotor air-cooling,were analyzed and compared from the aspects of the system's safety,economy,maintenance and so on.Results indicate that open forced air-cooling and outer water-cooling system has the best installation,maintainability and reliability,closed forced circular air-cooling and outer water-cooling system makes the motor's temperature rise symmetrically and prolong the motor's insulated life,stator water-cooling and rotor air-cooling system has low cooling expenses and the best cooling effect.The results could provide references to design and select motor cooling system.