单项选择题
A.too much superheat B.insufficient superheat C.suction pressure too low D.excessive refrigerant returning to the compressor
Which bearing will carry the load on two small points d...
单项选择题Which bearing will carry the load on two small points diametrically opposite to each other?（）
A.Needle B.Tapered roller C.Roller D.Ball
Refrigeration system compressor crankcase sweating is a...
单项选择题Refrigeration system compressor crankcase sweating is an indication of （）.
A.insufficient lube oil circulating through the system B.excessive circulation of lube oil through the system C.insufficient refrigerant in the system D.an overworked compressor
Operating a rotary pump at speeds in excess of design r...
单项选择题Operating a rotary pump at speeds in excess of design requirements could cause（）.
A.decreased clearances between rotating parts B.decreased slippage to the suction side of the pump C.air binding in the discharge ports D.erosion and excessive wear
