The starting air entering the cylinder begins when the piston（） -题库考试答案搜索网

The starting air entering the cylinder begins when the piston（）

单选题

2022-01-04 04:44

A、has nearly come to the TDC
B、has just past the TDC
C、has nearly come to the BDC
D、has just past the BDC

查看答案

正确答案

B

试题解析

标签：船舶电气与船舶安全

感兴趣题目

When the air charge contacts with the cylinders and pistons and mixes with the residual gases, it will（）

Charging is the filling of the engine cylinder with a supply or charge of fresh air （） compression.

The loss of the diesel engine cylinder air charge through leaky valves, piston rings, worn or scored liners, would be indicated by which of the following sets of conditions?（）

The air cylinder bottles in the survival craft should be refilled with（）.

（） is used for cylinder and cylinder head, the salt water is used for cooling the lubricating oil, the fresh water in the coolers and the charging air in the air cooler.

The air cylinder bottles in the survival craft should be refilled with（）.

An after-cooler installed between the turbocharger and the cylinder air inlet （）

（） device is provided to prevent starting air from being admitted to the cylinder before the reversing is completed.

In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）, there being an adequate overlap between the inlet opening and the exhaust closing.

The air is （）. Don’t enter that area.

When the order （） is received from the bridge, the main air stop valve in the starting air line should be shut.

In the starting system, the automatic valve is controlled by（）, and the cylinder start valves are controlled by（）

相关题目: 第二组Under normal operation, some lubrication oil mist may be discharged from the air compressor to the air start system. This oil may be from excess compressor cylinder lubrication, from faulty oil scraper rings, or may even be suspended oil vapor contaminating the engine room atmosphere and drawn in at the compressor suction. Oil discharge is kept to a minimum by draining the after cooler, air receiver and starting system. If small quantities of lubrication oil do get passed into the starting air system, they will deposit as thin moist film over internal pipe surfaces but are not readily combustible. If a cylinder non-return valve leak while the engine is in operation, some hot gas, possibly with unburned fuel and cylinder lubrication oil, may be blown through the valve to the adjacent air manifold. With further heating from the leaky valve, this, together with the already deposited oil film, will carbonize and form. incandescent carbon. If starting air is applied to the system while still hot, the high pressure air coming into contact with the burning carbon may cause an explosion. Such an explosion will cause a flame to pass back through the air start pipe system, evaporating the deposited oil film and igniting it in the presence of air. Very high velocities and shockwaves are generated which may rupture pipes and fittings.Alternatively, if excessive oil has entered the air start system, a mixture of air and oil droplets may be discharged through the open cylinder non-return valve during starting. This spray may ignite due to high temperatures in the cylinder, causing a flame through the still open valve to the air manifold.To prevent an explosion, air start valves must be correctly maintained and lubricated to ensure correct timing and free movement with positive closing. Oil in the system must be kept to a minimum, pipe lines must be drained and cleaned internally when necessary and oil discharge from air compressors must be kept to a minimum by good maintenance.The passage is mainly about; Diesel engines are started by supplying （） into the cylinders in the appropriate sequence for the required direction.; Diesel engines are started by supplying （） into the cylinders in the appropriate sequence for the required direction.; If a four-stroke/cycle diesel engine is started by injecting air into the cylinder, the pistons receiving the charge of starting air must be（）; The forced draught fan should be started and air passed through the furnace for several minutes to “（）” it of any exhaust gas or oil vapors.; When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）; When starting an engine, the compressed air enters the cylinder when the corresponding piston is in position of its（）; When the starting air valve closes on one cylinder, another starting air valve has （） opened on another cylinder whose piston has just commenced its downward stroke.; Pump up the starting air reservoirs to their maximum pressure and （）the air reservoirs and air system.; （） supplies pilot air to control the cylinder air start valves.; In the suction stroke air is induced into the cylinder （）In the compression stroke the air is compressed.; The pressure of pilot air is usually （） than that of starting air.; The primary task of the compressed air system is to deliver the starting air necessary for （）; The starting air entering the cylinder begins when the piston（）; Usually we take the cooling effect of the air flown through the cylinder during the overlap period as（）; How does combustion air enter the cylinder of a two-cycle diesel engine?（）; （） is usually driven by the engine camshaft and supplies pilot air to the cylinder air start valve.; The starting air bottle should be pumped up to maximum pressure by the （） before start of the engine.; Before starting the engine the air bottle should be （）.; Open the （）before starting an air compressor.

广告位招租WX:84302438

题库考试答案搜索网

免费的网站请分享给朋友吧