[单选题]What’s the advantage of oily water separator that meets the requirement of MEPC 107(49) over MEPC 60(33)?
[单选题]The high-pressure fuel opens the fuel valve and is sprayed into the cylinder in tiny droplets known as ____.
[问答题]Babcock Internal furnace type boiler is essentially similar to the Foster Wheeler D type, the initial design of both being in the USA. Differences between them are confined to detail and to specific proprietary features. For example, Babcock boilers of that time used studded tubes in the furnace walls with the spaces between studs and between adjacent tubes packed with plastic chrome ore. This was an excellent refractory material but lacked mechanical strength and so 12 mm round studs of varying length were electric resistance welded to the furnace wall tubes to reinforce and support the refractory. This proved a very durable construction but in time it became difficult to obtain spares worldwide wherever ships called in for repairs. Eventually bare tubes on a tangent pitch were used, as in the D type. All Babcock boilers incorporate patent steam separating cyclones in the steam drum through which the steam/water mixture from the heated tubes is caused to pass. Inside the cyclones a vortex is formed creating a significant separation force causing steam free water to exit at the bottom and dry steam to leave at the top. These, together with a conventional slotted dry pipe , ensured dry steam to the super-heater and steam free water to the down-comer tubes. As already observed the latter ensures a brisk circulation whilst the former was found to be effective over a very wide range of drum water level and practically eliminated all risk of scale build up inside the primary super-heater tubes. To assist separation of steam and water in Foster Wheeler boilers, arrangements of perforated plates were used, although on occasion a form of cyclone was adopted with a horizontal axis as opposed to the vertical arrangement use by Babcock.
[单选题]The company should establish procedures to ensure that the ship is maintained ______the provisions of the relevant rules and regulations.
[问答题]The Sulzer multi-level accumulator system for cylinder lubrication has proved particularly beneficial to good piston-running behavior. The cylinder oil is fed to the liner surface at two levels of quills. This lubricating oil and is therefore considered to be efficient and economical. The lubrication oil pumps are driven by a frequency-controlled electric motor and the oil is distributed to the quill accumulators by oil distributors. With this solution, much less piping is required. The cylinder oil feed rate is controlled according to the engine load. Adjustments depending on the engine condition and for running-in can be easily made by using software in the engine control system.
[单选题]When removing a centrifugal pump for inspection and maintenance, __________ and _______ pump electrical circuit breaker on main switch board.
[单选题]The piston rod stuffing box incorporated in a two-stroke/cycle, crosshead diesel engine serves to ______.
[单选题]After received the “finished with engine” order from bridge, which of the following operations is false?
[单选题]Provision must be made in pipe systems for changes in length due to change of temperature. The bold and italic word “provision'' probably means
[单选题]In the design of hydraulic piping and equipment consideration is given to minimize turbulence in the hydraulic fluid, as this will cause _______ .
[单选题]If you cannot extinguish the fire on your own in two minutes, you must _____. ①raise the fire alarm ②try to control the fire ③find out what is burning by the color and odor of the smoke ④run away from the fire location
[问答题]Severity of explosions vary between a puff which may lift a relief valve to a violent explosions which causes major damage and may injure personnel and cause a fire. Evidence indicates that the longer the combustion path, the more violent the explosion. This has become an area of concern with the large two strokes of today which may have a crankcase volume of 500m3. When an explosion occurs a flame front travels down the crankcase with a pressure wave in front of it. The turbulence caused by moving engine components causing churning and mixing of vapors increase the speed of the flame front and its area, which contribute to the increase in pressure. Turbulence caused by venting of the pressure through relief valves can also influence the explosion. Following the venting of the explosion through the relief valves, there is a drop in crankcase pressure to below atmospheric pressure. This can cause air to enter the crankcase resulting in another flammable mixture to be developed resulting in a secondary explosion to occur. The secondary explosion is more violent and can result in crankcase doors being blown off the engine, and fires starting in the engine room. If the relief valves do not reseal after lifting, or if they do not lift at all in the primary explosion ( due to lack of maintenance etc), then door(s) may be blown off in the primary explosion, giving a ready path for the ingress of air, which will make a secondary explosion more likely. Air can also be sucked in via the crankcase vent, although rules state that this must be as small as practicable and new installations must have a non return valve fitted. If a primary explosion occurs, the pressure wave may send a large amount of oil mist out into the engine room. Although the flame arrestors on the relief valves should prevent ignition of this oil mist by the flame front, the mist will be sucked up towards the turbocharger where it may be ignited by an un-lagged hot exhaust manifold. This ignition of oil mist can cause severe damage to plant and personnel.
[单选题]Large crosshead type engine generally has two lubrication systems, a function performed only by crankcase oil system is _______,
[单选题]In some cases,______are employed to maintain the main bearing housings and engine block in compression.
[问答题]Turbocharging is a method by which energy in the cylinder exhaust gas is used to provide air for combustion. Four-stroke cycle engines may operate in a normally aspirated mode, which means that the suction stroke of the piston draws air into the cylinder and so no pressurized air supply is necessary. A two-stroke cycle engine requires air to be supplied at a pressure above atmospheric and so some means of providing that pressurized supply is necessary. A four-stroke cycle engine can, therefore, operate without a pressurized combustion air supply but a two stroke cycle engine cannot. However, the operation of a pressure charged four-stoke engine under non-pressure charged, or nor really aspirated conditions, is not advised as it is likely to result in severe fouling and possible there real damage.
[单选题]While overhauling a jerk-type fuel pump it is necessary to replace the pump plunger. Which of the parts listed below must also be replaced?
[单选题]If the PSCO uncertain the source of water pressuring during the inspection of fire main system, in such case, you can test ______for him.
[单选题]The engine is controlled and monitored via the ECS, this platform encompasses following integrated units: _____. I. the engine interface control units (EICU) II. engine control units (ECU) III. auxiliary control units (ACU) IV. Alpha lubricator (ACC) V. cylinder control units (CCU)
[单选题]For vessels with ____,the meaning of the order would include the combination of pitch and revolutions as indicated in ships orde
[单选题]Hydraulic system reservoirs are often fitted with a combined filler/breather cap. If the breather element becomes fouled, the _______.
[单选题]The cooling water is in direct contact with the outer surface of the liner as a result of which it is termed a “____”.
[单选题]Prior to a ship’s departure from any port ______should be tested with deck officer to ensure satisfactory operation.
[单选题]The main functions of CCS are to perform ______ of ships, offshore installations, containers and related industrial products both at home and abroad, and to conduct statutory work on behalf of the Chinese Government and other flag administrations when so authorized as well as other businesses approved by relevant administrations.
[单选题]Alpha ACC allows the cylinder oil dosage (g/bhp) to be controlled in such a way that it is ______ the amount of sulphur (g/bhp) entering the cylinder with the fuel.
[单选题]The additional mark _____ in the Classification Certificate for Machinery represents the propulsion apparatus is remotely controlled on the navigating bridge control station, and engine room is watched by duty personnel.
[单选题]The pitch p is ______ that the propeller “screws” itself forward through the wa?ter per revolution, providing that there is no slip.
[单选题]When a ship in loaded condition floats at an arbitrary water line, its displace?ment is _____the relevant mass of water displaced by the ship.
[单选题]If a vessel moored at a U.S terminal does not comply with coast guard pollution prevention regulation, it may be detained by the ____.
[单选题]For a continuous operating diesel engine, a duplex filter unit would be the best arrangement because_____.
[单选题]The loss of a ______ results in misfiring on one or two cylinders. Also cylinder lubrication is lost on the respective cylinders
[单选题]Which of the following items can cause the failure to deliver water? Ⅰair leakage in the suction pipe Ⅱthe filter is choked Ⅲ the suction lift is too high Ⅳ the impeller is broken Ⅴ there is air in the water Ⅵ the discharge head is too high
[单选题]As to the low speed diesel engine, if you want to change the coolant flow for a certain cylinder, you can regulate____.
[单选题]If a crankcase explosion has occurred in a diesel engine, and the crankcase remains intact,which of following precautions should be observed?
[单选题]The adverse effects of burning high sulfur fuel can be compensated for by using a cylinder oil having sufficient_____.
[单选题]A gudgeon pin in a trunk piston may be free to float and rotate, with ______to limit axial movement.
[单选题]The hydraulic oil most likely to thin out when hot and thick when cold would have a viscosity index of ______
[单选题]When in operation, it is unavoidable that a small amount of oil_____through leakage, and in order to compensate for these leaks the system is connected to a feed pump.
[单选题]Most practical diesel engines today operate on cycle which is a combination of the Diesel and Otto cycles. In this process, compression ignition ______
[单选题]The plunger in a jerk pump is rotated until the release port is uncovered. If the port remains uncovered all of the time, which of the listed operations will occur?
[单选题]For a main diesel engine the lube oil in the bearings is drawn from ___, usually located in the bedplate.
[单选题]_______are increasingly used as main engine on merchant vessels, because they have a high Hp/Weight ratio.
[单选题]In order to inspect both piston and cylinder wall thoroughly, the cylinder cover should be taken off and the piston should be ____ .
[问答题]In the event of a main generating system failure an emergency supply of electricity is required for essential services. This can be supplied be batteries, but most merchant ships have an emergency generator. The unit is diesel driven and located outside of the machinery space. The emergency generator must be rated to provide power for the driving motors of the emergency bilge pump, fire pumps, steering gear, watertight doors and possibly fighting equipment. Emergency lighting for occupied areas, navigation lights, communication systems and alarm systems must also be supplied. Where electrical control devices are used in the operation of main machinery, these too may require a supply from the emergency generator. Usually only one emergency switchboard is installed, however, for safety reasons large passenger vessels may have two emergency sources of power, thus requiting two emergency switchboards. Emergency switchboards normally consists of a generator control panel, a bus tie and distribution panel and 24-volt, 120-volt and 450-voh distribution panels in size and number as required. Emergency generator switchboard includes those devices noted in the foregoing for main switchboard generator control panels plus the following: 1. A white light to indicate that the normal supply is available. 2. A green light to indicate that all devices are “set up” for automatic operation. 3. A normal supply circuit breaker, unless the automatic bus transfer is of the contactor type. 4. A feed back switch when the automatic bus transfer is of the contactor type. It is not usual for an emergency generator to require paralleling, so no equipment is provided for this purpose. Automatic start up of the emergency generator at a low voltage value is usual on modern installations.