你可能感興趣的試題

The purpose of the safety relief valves installed on an auxiliary boiler is to （）.

A.relieve excess fuel oil pressure during the “off” fire cycle
B.admit water to the dry pipe
C.throttle the forced draft fan output for proper combustion
D.reduce excess steam pressure in the boiler

單項選擇題

The pH value of water in a diesel engine closed cooling water system should be maintained between （）.

A.60 to75
B.80 to 95
C.100 to 115
D.120 to 135