Positive displacement, helical gear pumps are well suited for pumping oil becauseA.stuffing boxes eliminate the leakage problems usually associated with other gear pumpsB.it is not necessary to closely maintain design clearances with this pumpC.they are essentially self-priming and produce a high suction liftD.these pumps are designed with extreme tooth angles
Positive displacement, helical gear pumps are well suited for pumping oil because
A.stuffing boxes eliminate the leakage problems usually associated with other gear pumps
B.it is not necessary to closely maintain design clearances with this pump
C.they are essentially self-priming and produce a high suction lift
D.these pumps are designed with extreme tooth angles
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GEAR路由协议不适合在移动WSN使用。