下面哪个是储蓄机构________。

单项选择题The_______in the steering gear move the rudder to the required angleA.control equipmentB.power unitC.transmission mechanismsD.fittings and pipeline

单项选择题Before doing any work on a hydraulic system equipped with accumulators, you shouldA.drain the accumulators and purge with oxygenB.bleed off all stored energy from the accumulators completelyC.charge the accumulators to prevent system energy lossD.pump the hydraulic fluid into the accumulators to prevent fluid loss