[问答题]Please carefully read the following table and then answer the questions according to the information from this table. Table: types of fire extinguisher
[单选题]Fuel oil is thought to be one of the main factors _____the operation and maintenance of an engine.
[单选题]Improper seating of an air starting check valve in an operating diesel engine is indicated by _____.
[单选题]In an auxiliary diesel engine bypass type lubricating oil system, the main oil pump forces ______.
[单选题]To counteract these undesirable effects cylinder oils usually contain additives formulated to impart a high degree of _____ and detergency.
[单选题]Early stern-tube bearing used bearing materials such as lignum vitae which were lubricated by ______.
[单选题]Large crosshead type engine generally has two lubrication systems, a function performed only by crankcase oil system is _______,
[问答题]The separation efficiency of the ALCAP separation system has been thoroughly tested with respect to removal of water, catalyst fines and other inorganic solid particles. A detailed review and report on results from the laboratory and shipboard tests are presented in Enclosure 2. These tests were made together with Shell International and Sulzer. The densities of the tested oils were 991,993 and 1013 kg/ m 3 at 15℃. The test results are summarized as follows: --seawater contamination is efficiently reduced in heavy fuel oil with densities up to 1013 kg/m 3 at 15 ℃. --catalyst fines and other inorganic solid particles are efficiently removed from heavy fuel oil with densities up to 1013 kg/ m 3 at 15℃. --freshwater contamination is efficiently reduced in heavy fuel oil with a density of 993 kg/ m 3 at 15 ℃. Example: 3 % freshwater was reduced to 0.5 %-0.6 %. However, the upper density limit for satisfactory reduction of freshwater is probably higher, up to 1010 kg/m 3 . Additional tests are planned to confirm this. --the separation efficiency of the ALCAP separation system is as good as or better than a well adjusted purifier (applicable for heavy fuel oil with density up to 991 kg/m 3 at 15℃ ). --laboratory and shipboard tests conducted to date confirm that the ALCAP separation system delivers optimum separation efficiency, continuously. Based on these findings, the recommended maximum density of heavy fuel oil cleaned with the ALCAP separation system is lO10kg/m 3 at 15℃ measured at 50℃ .The recommended maximum viscosity is 700 cst at 50℃.
[单选题]Besides the metric ton (1,000 kg), there is the English ton (1,016 kg), which is also called the “______”.
[单选题]Which of the following problems represents one possible cause of high lube oil consumption in a four-stroke diesel engine?
[单选题]Lube oil filters remove contaminants from oil more efficiently if the oil being filtered is____.
[单选题]Some diesel engines are fitted with a thermometer in the cooling water outlet from each cylinder. If the cooling water temperature from all cylinders begins to rise above normal, you should suspect________.
[单选题]Fuel of different qualities may require advancing or retarding the injection timing, in addition to which if the injection timing is advanced when the engine is running at loads below the ____.
[问答题]A two-ram hydraulic gear consists of a hydraulic ram situated on the port side of the tiller and another ram on the starboard side, linked at their outer ends to the tiller arm by a crosshead and swivel block, the other ends of the rams working inside their own hydraulic cylinders and pipes connect these cylinders to a hydraulic pump. The tiller is firmly keyed to the rudder stock. The pump is of special construction and may be axial or radial design. The pump runs continuously in the same direction driven by an electric motor, and the position of a movable plate or a floating ring inside the pump controls the suction and discharge of the oil. When the plate or ring is in mid position, no oil is drawn; when the plate or ring is moved in one direction from mid position, oil is drawn from one cylinder and discharged into the other; when the plate or ring is moved in the opposite direction, the suction and discharge of the oil is reversed in direction. The plate or ring is actuated by a control rod which is attached at its outer end o the hunting gear. A four-ram hydraulic steering gear may be fitted in large ships for greater steering power, instead of the tow-ram type. It is simply a double tow-ram unit, so that the force of tow diagonally opposite rams can act on the tiller to produce double the turning effect. The pump control is moved by the telemotor through a floating lever. The other end of this lever is connected through a safety spring link to the rudder stock or tiller. The telemotor is the receiver of the hydraulic remote control system from wheel on the bridge. The linkage through the floating lever of telemotor, pump and rudder stock forms the hunting gear.
[单选题]When a point rotates about an axis and at the same time, moves parallel to that axis, it describes ( ).
[单选题]If lost motion is present in an individual fuel injection pump, which of the following problems will occur?
[单选题]In the lubricating oil system on an auxiliary diesel engine a duplex filter unit is used because____.
[单选题]In an oil cooler circulated by sea water, the oil is at a larger pressure, the result being that any leak in the cooler will mean a loss of_____.
[单选题]The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices, during ______.
[单选题]Which of the following reasons represents why the designed compression ratio of a gasoline engine is lower than that of a diesel engine?
[单选题]If there are micro-seized areas on the liner or skirt, scratch-over manually with a coarse carbo-rundum stone, moving the grindstone_____at an angle of 20 to 30 degrees to horizontal.
[问答题]Supercharging and Scavenging Air supply is very important to the perfect combustion of fuel oil in the diesel engine. As the air density determines the maximum weight of fuel that can be burned per working stroke in the cylinder, it also determines the maximum power that can be developed by the engine. If the charge-air density is increased by a compressor before it enters the cylinder, a greater amount of fuel can be burned, resulting in an increase of power output. This is the main principle of exhaust turbo-charging. In today’s practice, the compressor, i. e. a blower, is driven by the heat energy obtained from the engine exhaust gases. The turbo-blower comprises a gas-turbine, driven by the engine exhaust gases and directly coupled to the blower, which draws fresh air from the engine-room and discharges it into the air inlet manifold on the engine. The power produced in the turbine must be equal to that required by the compressor. The air is pumped into the cylinder through the inlet ports. The turbo-blower is provided with a filter-silencer. It is usually desirable to fit charge-air coolers to turbo-charged two-stroke engines. As the charge-air density increases, the amount of air flowing into the cylinders is increased and as the charge-air temperature lowers, the exhaust temperature and the engine thermal load are reduced. It is very important that each cylinder should be well scavenged before the charged air is com- pressed, otherwise this fresh air charge will be fouled by the residual exhaust gases from the last cycle. The necessary scavenging is obtained by providing a satisfactory pressure difference between the air manifold and the exhaust manifold.
[单选题]Diesel engines driving alternators operating in parallel must maintain a set frequency regardless of load changes. The governor characteristic used to accomplish this is known as ______.
[单选题]Large, slow speed, two-stroke marine diesel engines offer the advantages of the following except _________.
[单选题]In addition to lubricating, cylinder oil assists in forming a gas seal and contains _____which clean the cylinder liner.
[单选题]What determines the number of events occurring in a cycle of operation in an internal combustion engine?