| 摘要 |
PURPOSE:To prevent the generation of cavitation in a liquid handled by the pump by a method wherein a part of the handling liquid in the delivery side of the pump is increased in the pressure thereof by an auxiliary pump and is returned to the delivery side of the pump to circulate it and keep the pressure thereof at a high pressure. CONSTITUTION:When a canned motor pump 20 is operated, a part of the pump handling liquid 67, energized by pump impeller 47 and increased in the pressure from a pump suction pressure P0 to a pump delivery pressure P1, is introduced into the suction side 55 of the auxiliary pump 50 from the delivery side 54 of the pump through a path 56. The oil is energized again by the impeller 49 of the auxiliary pump to increase the pressure thereof to the delivery pressure P2 of the auxiliary pump and is flowed into the fore end of the canned motor 21. The pump handling liquid 67, passed through the canned motor 21, has a sufficiently high pressure and, further, it is returned to the delivery side 54 of the pump, therefore, there exists no possibility to cause cavitation. |
