Дизельные двигатели. Эксплуатация и обслуживание = Diesel engines. Operation and maintenance. Практикум
.pdf12.What data is shown on the bunker receipts or invoices?
13.Who checks, signs, and seals the bunker receipts?
14.What must the chief engineer do in case of abnormal discrepancy between his figures and the figures shown on the deliverer’s invoice?
3. In the following multiple-choice test choose an end / answer that logically would match the beginning of each statement / question.
1.When the opening pressure of a diesel fuel injector is lower than that specified (указанное) by the engine manufacturer, the ...
a) quantity of fuel injected tends to be increased
b)quantity of fuel injected will always be decreased
c) start of injection will always be retarded (запаздывать)
d)duration (длительность) of injection will always be reduced
2.Individual cylinder performance of a diesel engine is commonly determined (обычно определяется) by exhaust gas ...
a) pyrometre readings (показания) b)chemical analysis
c) Pressure readings d)Infrared analysis
3.A characteristic of rubber or neoprene (неопреновых) stern tube bearings is ...
a) the bearings are lubricated by seawater b)no stern tube packing is required
c) neoprene bearings are less abrasion resistant than bronze bearings d)neoprene bearings are not damaged by propeller shaft vibration
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4.Most main propulsion unit reduction gear bearings are ...
a) self-lubricating b)self-aligning
c) spherically seated
d)rigidly (жёстко) mounted
5.During the power stroke of a 4-stroke cycle diesel engine, most of the side thrust of a trunk piston connecting rod is absorbed (поглощается) by the ...
a) piston skirt (юбкой)
b)pinion (ведущей шестернёй) c) crosshead
d)compression rings
6.Bearing clearances in small high speed diesel engine should be measured with ...
a) gauge blocks (калиброванными прокладками)
b)plastigage (инструментом для измерения зазоров в подшипниках скольжения)
c) feeler gages (щупами)
d)round solder wire (проволочным припоем)
7.If the compression rings on a diesel engine piston become stuck (застряли), the cause may be ...
a) excessive cylinder pressure b)excessive cylinder lubrication
c) improper (неправильное) ring rotation d)improper ring action
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8.Reducing the clearance between a valve stem and rocker arm will result in the valve ...
a) having a shorted open duration b)having a longer open duration c) closing sooner
d)opening later
9.Late fuel oil injection in a diesel engine could result in ...
a)fuel knock
b)increased power
c)low compression pressure
d)high exhaust temperature
10.A substantial (значительное) increase in crankcase pressure could be an indication of ...
a) excessive lube oil pressure
b)the proper seating of new rings c) a worn cylinder liner
d)a malfunctioning cylinder relief valve
11.A diesel engine is turned at normal cranking speed with starting air pressure and no ignition occurs (не происходит). This could be the result of ...
a) low lube oil temperature
b)low starting air temperature c) air in the fuel-oil system
d)water in the starting air system
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12. If an air start diesel engine begins to rotate in the wrong direction
when starting air is applied, ...
a)one or more fuel valves is leaking
b)the starting air valve did not open completely
c)one or more starting air valves is leaking
d)the starting air pressure is too low
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13.OPERATION AND MAINTENANCE
1.Read and translate the text. Pay attention to new phrases.
Operation and Maintenance
Engine Maintenance
Keeping an internal combustion engine in good operating condition demands a well-planned procedure of periodic inspection, adjustments, maintenance, and repair. If inspections are made regularly, much maladjustment can be detected and corrected before a serious casualty result. A planned maintenance programme will help to prevent major casualties and the occurrence of many operating troubles. Routine maintenance must be performed as soon as possible; if repair jobs are allowed to accumulate, the result may be hurried and incomplete work.
There are several general rules, which apply to all engines, as regards their maintenance. They are:
1.Detailed repair procedures are listed in manufacturer’s instruction manuals and maintenance pamphlets. Study the appropriate manuals and pamphlets before attempting any repair work. Pay particular attention to tolerances, limits, and adjustments.
2.The highest degree of cleanliness must be observed in handling the parts during overhaul.
3.Before starting repair work, be sure that required tools and replacements for defective parts are available.
4.Detailed records of repairs should be kept. Such records should include the measurements of parts, hours in use, and new parts installed. An analysis of such records will indicate the hours of operation that may be expected from the various engine parts. This
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knowledge is helpful as an aid in determining when a part should be renewed in order to avoid a failure.
5.Detailed information on preventive maintenance is contained in the special manuals.
6.Certain operating checks and inspections are required as a normal part of the regular watch standing routine, such as hourly pressure and temperature checks or routine oil level checks.
keep an internal combustion engine in good operating condition
detect maladjustment
prevent major casualties
perform routine maintenance
detailed repair procedures
pay particular attention to tolerances, limits, and adjustments
handle parts
replacements for defective parts are available
part should be renewed in order to avoid a failure
preventive maintenance
study the appropriate manuals
2. Answer the question: In what way is the internal combustion engine kept in good condition?
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14.AUXILIARIES. SHIP’S PIPING SYSTEMS
1.Read and translate the text. Pay attention to new phrases.
Ship’s Piping Systems
Since the maintenance and operation of all ship’s systems is the responsibility of the engine department, the engineer officers have to work with piping, fittings, valves, and insulation. Each piping system consists of sections or lengths of piping, fittings for joining the sections, and valves for controlling the flow of fluid. Most piping systems also include other fittings and accessories such as vents, drains, traps, strainers, relief valves, various gauges: vacuum metres, pressure gauges, thermometers, and other measuring instruments. Piping sections of the proper size and material and connected by various standard fittings including threaded, bolt-flanged, welded, bent, and expansion joints. Strainers are fitted in all pipelines to prevent the passage of debris, grit, scale, dirt, and other foreign matter. Such matter could obstruct pumps, throttle valves, or damage machinery parts.
In order to make the machinery operate properly, the engineers must know how to make minor repairs to insulation, repack high pressure valves, overhaul and adjust valves, select the right packing and gaskets, and make permanent repairs to pipelines. Working with ship’s systems implies the following actions: maintaining the systems in a condition of constant readiness and good working order at all times; frequent examining of the lines; keeping all joints, valves and cockpits tight; eliminating any leaks at joints by tightening connecting bolts or packing nuts; replacing gaskets or any defective parts; cleaning strainers at recommended intervals, etc. Making repairs to pipelines and accessories implies doing such corrective actions as: removal of
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strain on pipes; removal of pipe vibration; keeping steel or iron piping properly painted and free from moisture; repairing leaky pipes or fitting by welding; brazing; plugging blow-holes or stopping leakage with clamps; renewing worn-out or damaged parts; overhauling, repacking and adjusting valves, etc.
The future marine engineer should be particularly acquainted with the following piping systems:
1.The bilge drainage system, which is designed to collect drains from compartments that cannot be drained overboard by gravity and to pump this bilge water overboard. To prevent oil mixed with the bilge water from being pumped overboard, the bilge water must first go to an oily water separator.
2.The fire-main system, which supplies sweater under pressure to all the fire stations, and to the deck and anchor wash connections. The fire-main system is the ship’s first means of defence against fire. It is required no matter what other fire extinguishing systems are installed.
3.The water ballast system, designed to load and discharge the fore and after peak tanks, and in some cases one or more deep tanks, with clean salt-water ballast. The purpose of the system is to maintain the proper trim, stability, and immersion of the vessel.
4.The sanitary and grey water drainage systems. The sanitary system flushes toilet bowls and urinals. The grey water system is completely separate and drains showers, sinks, laundry, and interior deck drains. Since the grey water is free of harmful bacteria, it is drained directly overboard. No one should dump waste oil down these drains since it will go directly overboard, causing oil pollution. Sanitary sewage is collected in a special tank and then sent to sewage treatment plant. Sanitary discharges are equipped with an automatic non-return valve to prevent water from passing inboard.
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5. The fresh water system must be entirely independent of all other piping systems; blank flanges, bypasses and other connections are illegal. Drinking and washing water system are often combined. The washing water system usually utilises several tanks located in the double bottom; it supplies fresh water to the washing appliances and other consumers. Drinking water is used mostly in the galley.
In the pressure system a pressure tank is located in the machinery space. This tank is filled with compressed air in its upper part and water in its lower portion. As water is pumped into the tank, the air is further compressed until a set pressure is reached when the pump stops. This compression maintains pressure on the system until the minimum point is reached when the pump is started again.
Hot water is supplied via a storage type water heater, which usually operates automatically under the control of a thermostatic valve.
The supply of drinking water on board is limited, and it is common practice to take water from shore side whenever practical. Most ocean-going vessels cannot store enough fresh water for a voyage and must have the capability to make fresh water. Fresh water is made from sweater by installations called distilling plants, or evaporators, or fresh water generators.
length of piping
fittings for joining the sections
vent
strainer
vacuum metres
threaded joint
bolt-flanged joint
welded joint
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bent expansion joint
prevent the passage of debris
make minor repairs to insulation
repack high pressure valves
keep all joints, valves and cockpits tight
replace gaskets
remove of strain on pipes
repair leaky pipes or fitting by welding
brazing
renew worn-out or damaged parts
bilge drainage system
maintain the proper trim, stability, and immersion of the vessel
sanitary and grey water drainage system
sewage treatment plant
store enough fresh water
distilling plant
evaporator
2. Answer the questions to the text.
1.What parts does a piping system consist of?
2.What accessories are used on piping systems?
3.What types of fittings connect pipe sections?
4.What foreign matter is retained by the strainers?
5.What corrective actions do the engineers have to do when working with piping systems?
6.What repairs are usually made to pipelines and accessories?
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