When running a large, low-speed, main propulsion diesel engine on heavy fuel, which of the
A. The diesel oil must never be allowed to mix with the heavy fuel
B. The temperature of the fuel from the pre–heater should be gradually reduced after switching over the three–way valve
C. The heating steam to the pre-heater should be secured as soon as the diesel fuel passes through the three-way valve
D. The heating steam must be secured before the diesel oil passes through the three-way valve
查看答案
根据加热、冷却方法的不同,热处理可分为()、()、淬火和()等。