抄録
A double acting bellows type liquid helium pump was developed for the cryogenic system of a large thin solenoid magnet. The pump performed the maximum capacity of 900l/hr and the maximum pressure head of 4.4×105Pa while the heat generation in the pump was only 200mW. The fatigue test of the bellows was made prior to the construction of the pump. It endured more than six million pumping cycles in liquid nitrogen temperature. The pulsation of the outlet pressure was largely reduced by use of oil-air cylinder actuation.