单项选择题
A.cylinder head water outlet header
B.cylinder jacket inlet main
C.heat exchanger inlet connection
D.jacket water pump suction line
单项选择题 Passages are drilled in the crankshafts of diesel engines to provide lubricating oil to the （）.
单项选择题 After a normal, or safety shutdown, automatic combustion control systems for an auxiliary boiler are designed to prevent the immediate refiring of a burner in order for the （）.
单项选择题 Maintaining the lowest possible scavenging air temperature at all times is not recommended due to the possibility of the （）.