船东英语口语面试 Part 5
1．How do you manage sewage?
Drop in sterilized medicine regularly. Keep the blower in constant working. Check the quality of the sample of the constant to compare with the standards.
2．Have you ever performed the auxiliary engine to combust heavy oil? What should be borne in mind when transferring oil from heavy oil to light oil?
I have worked on the auxiliary engine which combusts a combination of A and C oil. When transferring oil from heavy oil to light oil, the changing of temperature should not be rapid. 1*C to 2*C per minute is best. Meanwhile the viscosity change should be constantly observed. The temperature of the oil temperature to be heated varies in quality of the fuel oil. In general, 180cst needs to be heated to 95-105*C; 380cst needs to be heated to 130-135*C. the viscosity is under the control of approximately 2 anglers.
3．Could you tell the main reason for seeing the black smoke exhausted from the diesel engine?
The possible reasons are as follows; discharge valve damage or over load operation of diesel engine, or leakage of nozzle, or the incomplete combustion in the cylinder because not enough fresh air was pumped.
4．Could you tell the main reason for scavenge fire?
Ignition of carbon/oil deposits by;A. Prolonged blow-by.B. Slow combustion in cylinder, owing to incorrect atomization, or misaligned fuel jets.C. Blow-back through the scavenge air ports, owing to an incorrectly adjusted exhaust cam disc or large resistance in the exhaust system(back pressure not exceed 300 mm wc)D. The cylinder liner wear out of order or piston ring broken.
由于如下的原因，油／碳燃烧物沉积而导致扫气箱着火；A. 长时间的活塞环漏气。B. 由于不正常的雾化，或燃油喷射的不对中而引起燃烧的缓慢。C. 由于排汽凸轮盘不正确的定时或排汽系统背压过大（背压不能超过300毫米水柱）而导致燃气通过扫气口倒流。D. 气缸套磨损超标或活塞环断裂。
5．Could you tell the main reason for crankcase explosion?
Oil mist and hot spot; abnormal friction between sliding surfaces causing a hot spot. Hot spot can cause the oil falling on them to evaporate. When oil vapour condenses again, countless minute particle are formed, which are suspended in the air. A milky white mist develops, which is able to feed and propagate a flame if ignition occurs. The ignition can be caused by the same hot spot which caused the oil mist to form. The ignition will cause a tremendous rise of pressure in the crankcase, which will open the crankcase relief v/v momentarily. A very severe explosion can damage the crankcase door and cause fire in the engine room. Similar explosions can occur in the chain casing & scavenge air box.
6．What does the turbine super-charger surge?
There are basically five main reasons.High backpressure of the exhaust manifold and low flowing quantity; rapid change in load; insufficient supply of fuel oil or bad combustibility; failure of turbine blade, nozzle and diffuser; narrowed scavenging of air passage or scavenge fire;