assorted questions

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Bunker delivery notes It is a requirement of Regulation 18 that any fuel oil for combustion purposes delivered to and used onboard shall be recorded by means of a Bunker Delivery Note (BDN). This implies that a bunker delivery note shall be presented for e...very barge delivery and every grade. Bunker Delivery Notes are required to contain all specific information as follows: -Name and IMO number of receiving ship -Bunkering Port -Date of commencement of bunkering -Name, address, and telephone number of marine fuel oil supplier -Product name -Quantity (metric tons) -Density at 15 oC (kg/m3) -Sulphur content (% m/m) -A declaration signed and certified by the fuel oil supplier's representative that the fuel oil supplied is in conformity with regulation 14 and 18 (I.e. that the fuel supplied has a sulphur level below 4.5% and that the fuel is free from inorganic acid, does not include any added substance or chemical waste which either jeopardises the safety of ships, adversely affects the performance of the machinery, is harmful to personnel, or contributes overall to additional air pollution). Further, Resolution MEPC.96(47) recommends that the seal number of the associated MARPOL Annex VI fuel sample is included in the BDN’s for crossreference purposes. The BDN’s are to be kept on board and readily available for inspection at all times. It shall be retained for a period of three years after the fuel oil has been delivered on board. 1) lpg tanks construction material used2 ( INVAR: 36% nickel steel or 9% nickel steel- higher temp.) 2) what all certificate to be carried according to annex 6 ( IAPP and supplements: particulars of ship, control of emissions from ship* ozone depleting subs * NOx *SOx * volatile organic compound)

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Assorted Class 2 Questions and Answers..

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Page 1: Assorted Questions

Bunker delivery notesIt is a requirement of Regulation 18 that any fuel oil for combustion purposesdelivered to and used onboard shall be recorded by means of a Bunker Delivery Note(BDN). This implies that a bunker delivery note shall be presented for e...very bargedelivery and every grade.Bunker Delivery Notes are required to contain all specific information as follows:-Name and IMO number of receiving ship-Bunkering Port-Date of commencement of bunkering-Name, address, and telephone number of marine fuel oil supplier-Product name-Quantity (metric tons)-Density at 15 oC (kg/m3)-Sulphur content (% m/m)-A declaration signed and certified by the fuel oil supplier's representative thatthe fuel oil supplied is in conformity with regulation 14 and 18 (I.e. that the fuel supplied has a sulphur level below 4.5% and that the fuel is free frominorganic acid, does not include any added substance or chemical wastewhich either jeopardises the safety of ships, adversely affects the performanceof the machinery, is harmful to personnel, or contributes overall to additionalair pollution).Further, Resolution MEPC.96(47) recommends that the seal number of theassociated MARPOL Annex VI fuel sample is included in the BDN’s for crossreference purposes.The BDN’s are to be kept on board and readily available for inspection at all times. It shall be retained for a period of three years after the fuel oil has been delivered on board.

 1) lpg tanks construction material used2 ( INVAR: 36% nickel steel or 9% nickel steel- higher temp.)2) what all certificate to be carried according to annex 6 ( IAPP and supplements: particulars of ship, control of emissions from ship* ozone depleting subs * NOx *SOx * volatile organic compound)3) under which clause in ISM sms is there (part A: clause 1.4, part A is IMPLEMENTATION and part B is certification and verification)4) 4 harmonized survey or how certification of ship is harmonized.5) Actions taken during boiler uptake fire? (Boiler uptake fire is because of wet soot deposited during low steaming and also during uptake fire do not carry out soot blow reduce the load and stop the engine , cover the m/e t/c with the canvas so that no air is supplied).6) Needle vv lift. (1.4mm for 250 bar lifting pressure)7) Boiler corrosion how it happens and how to prevent. (Acidic corrosion-CO2, O2, OIL, CHLORIDES, BICARBONATES and pitting corrosion: scales such as calcium and magnesium salts.)8) accumulation pressure test in boiler (disturbed it so accumulation pr should not more than 10 percent of working pr. when boiler is firing on full load for boiler).9) how to reduce maintenance in exhaust vv (good quality fuel usage , vit adjustment, avoid running engine on low load, check fuel injection system, good scavenging, maintaining cooling water temp, check rotation of exhaust v/v)10) refrigeration gases how its classified according to environment hazard (ozone depletion potential- max R11, for R22 is 0.05 and global warming potential- max is R11….and R22 is 0.365)11) How induction motor works12) Contactors maintenance on starter what is the material of contactor (1. Check for loose, missing, broken contactors, 2. Cleaning and checking contact surfaces for improper wear or discoloration 3. Remove oxides from faces using fine files, main contacts are high conductivity copper coz they ll not heat

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up due to lower resistance, arcing contacts are made of sintered silver tungsten or other materials which don’t weld at high temps)13) rpm indicator how signal is carried to ECR. (optical or magnetic)14) Crane jib is cracked how u r going to weld. (arrest crack and weld plates)15) Junior engineer boxed back the purifier after cleaning then its found vibrating probable causes. ( bowl may not be cleaned properly, lock ring not tightening properly, bowled assembled with wrong parts, gear can be in damaged condition, bowl springs not fitted correctly, top bearing springs damaged, discs not properly assembled or tightened, some external tool left inside .)16) insulation of motor is found to be 0.5 mega ohms what we can do to bring back the insulation (dry the motor by heating lamp and then test insulation n put fast drying varnish, check visually for any wires broken)17) Crank pin ovality checking.SAE 20 means it ll have a viscosity of 20cst at 100 C and SAE 15W40 means viscosity of 40cst at 100 C and 15cst at 0 C.Bhowmik and Biswas18) Mooring arrangement on crude oil tanker. ( headlines, breast lines-athwart ship movt, spring lines- longitudinal movt., cable for towing)19) auto tensioning winch (20) Shredder plate21) LSA equipment in life boat. (6 hand flares> 15000 cd and 1 min, 4 rockets>30,000cd and 40secs, 2 buoyant smoke signals>3mins,anti-sea sickness tablets, tpa, portable fire extinguisher, search light, a manual pump, efficient radar deflector, food ration, fresh water, tool kit)22) squat effect.23) What is power factor? (Power factor is the ratio of true power to the apparent power. i.e. watt/volt amp.)24) residual magnetism (residual magnetism is the property in which certain amount of excitation remains back in the conductor even after removal of the magnets)25) Reverse power trip location and drawing. (In the A.C.B. pg 58- mc. g)  26) container capacity- how much load a container can carry (32tonnes for 40ft container)27) How container is placed on tank top with drawing. Pg 121- ship cons reeds)28) IOPP supplement ( pg 22- gautam sen)29) hyper mist system maintenance (a/e, m/e, incinerator, boiler, purifier- blow through with air, pump operation, if solenoid is functioning)30) Anchor not coming up, reasons? (windlass oil lvl low, anchor stuff, slipping of clutch, high oil temp cut-out, power failure, pump or motor not functioning, actuating valves prob. )31) About co2 sys, all values temp and test pr etc. (pipes-15years…h.p.sec-180bar, m.p.sec-80bar, l.p.sec-6bar, spring loaded safety v/v in main pipe-180bar, bottle-228bar, seal bursting disc-63 C, storage temp. -55 C)32) AE inlet vv big or exhaust vv big and y? (a/e inlet valves are bigger, no back pressure in t/c free flow, better scavenging exhaust gas expelled easily, and exhaust v/v is smaller due to less power required to open .)33) What and why material of sounding bob. (brass- not sparking, softer than steel)34) min. thickness of feeler gauge (0.01mm)35) causes of pump wear ring being worn (strainer faulty, bearing damage, cavitations, high temp. water, unbalanced impellar)36) Why ME piston rings are little down and AC compressor piston rings are up? (m/e head is concave and head is flat….strength n more longer stroke)37) SCR system, ammonia slip, catalyst? (selective catalyst reaction- exhaust is mixed with ammonia and passed through a catalytic reactor, hence reduction in NOx. And soot in exhaust. Temp.-290-450 C. FINAL PRUCTS WATER AND NITROGEN PG 78-80 POUNDERS)

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ASTM means American society for testing of materials, it develops standard for materials, product, systems used in construction, manufacturing and transportation.SAE is society of automotive engineers; it gives the viscosity of oil based on a classification involving 2 temperatures38) if the dip stick breaks in co2 bottle then what will happen? (if co2 bottle dip stick is broken, till the length is ok, gas will come out. below the broken siphon tube co2 will freeze as latent heat is absorbed from the remainder CO2)39) composition of lpg, lng and cng (lpg-propane, butane, lng-metane, cng-methane)40) Maintenance on QCV? (try out once every 3 months, drain air bottle, check hand operation, spring condition, check piston)41) If life boat falls suddenly while lowering then how will u troubleshoot? (falls broken, falls releasing mechanism operated accidently, centrifugal break check)42) manhole door elliptical...why?( manhole door elliptical: longitudinal pressure = pd/4t or circumferential pressure=pd/2t where p=pressure, d=diameter, t=thickness...so circumferential pressure is more)43) Advantages and disadvantages of flare? (Flare advantage: prevents water to come to the deck, more space for deck machinery, avoids anchor from striking at bottom and improves buoyancy fwd. disadv.-more flare means parametric rolling…..when waves freq is half of rolling freq and same ass pitching freq)44) maintenance of induction motor45) Principle of battery operated phone?46) meggar operation? (pg-399, b.l.thareja vol1)47) Draw clampmeter? (48) Hydrometer working and diagram? (pg-145- d.t.hall)49) Working and diagram of lo pressure transmitter and trip? (50) Ammeter and voltmeter working?51) 3 causes of hysteresis loss in transformer? (residual magnetism, frequency )Mr. Sathapathy and Mr. Bhaira52) VIT. Draw curve between the angle of advance and Load. That is at what load what is the angle of advance draw the graph?53) Draw the diagram of mechanical over speed trip of a diesel engine54) What is the name of the device that measures vibrations of an engine and how does it function? (55) Economiser if the area of heat transfer is 1000 sq m what all will come under it and draw the construction of fins (surface area of fins and tubes)56) How does a soot blower works? How is chemical added to soot blower for release of soot and what are soot sticks?57) Why 3 injectors are used in modern 2 stroke engines (There will be better turbulence since three fuel injectors at an angle and the scavenge air enters at an angle so there will be better turbulence, there will be more proper heat dissipation in piston and cylinder head)58) Why steam is grey in color and not transparent? (water content in soot release)59) How does MGPS works? (2purpose: cu kills sea growth and al stops corrosion, the system is based on electrolytic reaction and dc supplied to anode)60) What is Muntz metal, monel metal, white metal compositions and which is more electrochemically active of them? (monel- copper-38 n nickel-60,al and manganese-2, white metal- tin-88, antimony-7.5, copper-4,lead-0.35, muntz metal-copper-60, zinc-40…..munz metal)61) A compressor was overhauled and bumping clearance was found to be normal inspite of that piston strikes the head. Give reasons? (in unloaded condition: Bottom end bearing wear down, or ?62) What is dealuminification where is it observed and why? (form of corrosion in which amount of aluminium decreases in an alloy…pumps, valves coz al is comparatively more reactive)63) Function of motor on governor (remote operation of speed setting knob-spring pressure)64) How to prevent Dezincification? (put soft iron)65) How will you make camshaft float while adjusting its position? (hydraulic pressure)

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66) Limitations of ODME (difficulty in analyzing- bad weather, muddy water, discharge capacity decreases as speed is measured)67) COFFIN PLATE (attaches sole piece in stern frame with keel plate in aft and attaches keel plate with stem in fwd)68) INTERNATIONAL SHORT VOYAGE (in which a ship is doesn’t exceed 200 nm and should not exceed 600 nm total)69) DETAILED INPSECTION OF SHIP ON WHICH BASIS IT IS CARRIED BY PSC.70) DESUPERHEATED STEAM. WHY AFTER SUPERHEATING WE ARE USING DESUPERHEATER (is to reduce the temperature of a quantity of superheated steam and make it suitable for auxiliary uses. Steam passes through super heaters to avoid overheating of them.)71) COP OF REFERIGERATION. (A refrigerator is a device for removing heat at a cold temp so heat absorbed in the evaporator fi(in),the cop is also called advantage and is defined as C.O.P. In a refrigeration cycle, the ratio of the heat energy extracted by the heat engine at the low temperature to the work supplied to operate the cycle; when used as a heating device, it is the ratio of the heat delivered in the high-temperature coils to the work supplied)72) GUGEON PIN CLEARNCE, HOW TO MEASURE AND WHAT IS TYPE AND MATERIAL OF BRG USED. (low carbon, case hardened steel)73) RMG45 AND RMG 55, GRADE OF OIL, WHAT IS DIFFERNCE? (74) WHEN REMOVING LOWERHALF MAIN BRG.IT IS STUCK WHAT WILL YOU DO? (sanyal 250)75) STUFFING BOX OVERHAULING?76) SOOT BLOWING DIFFERNT METHOD AND ARRANGEMENTS, WANT THE ULTRASONIC TYPE HOW IS WORKING? CHEMICAL TYPE, WHAT TYPE OF CHEMICAL? (sodium chloride, magnesium oxide, cupric chloride, zinc oxide, copper oxide)77) DRY DOCK STRENTUBE CHECKS? (liner, seals, bearing condition)78) WELDING DEFECTS, REASONS.79) Where do you find underslung bearing in Man B&W main engine (camshaft bearing)80) Refrigerant properties? (pg-335 mc. G: the heat of vaporization of the refrigerant should be high, the specific heat of the refrigerant should be low. the specific volume of the refrigerant should be low to minimize the work required per kg of refrigerant circulated, since evaporation and condenser temperatures are? xed by the temperatures of the surroundings - selection is based on operating pressures in the evaporator and the condenser selection is based on the suitability of the pressure-temperature relationship of the refrigerant other factors include chemical stability toxicity cost environmental friendliness does not result in very low pressures in the evaporator (air leakage) does not result in very high pressures in the condenser (refrigerant leakage) OR condensing pressure should be moderate. b) But the pressure should be preferably above the atmospheric pressure so as to prevent air from entering the system in the event of leak. c.) Low freezing point d.)Volume of refrigerant gas need to be pumped per ton of refrigerating effect should be low. d.) it should have high thermodynamic efficiency. Thermodynamic efficiency is the ratio between heat abstracted by the refrigerating machinery and the heat equivalent of the power supplied the compressors e.) it should not be flammable or explosive. f.) it should not be toxic. g.) the tendency of a refrigerant to leak should be low, and the detection of leak should be easy. h.) for good heat transfer viscosity should be low, thermal conductivity high. i.) it is preferred that there should not be a chemical reaction between the refrigerant and the lub oil. j.) cheaper in cost. k.) non corrosive, non flammable, chemically stable, non explosive, miscibility with oil, ozne depletion potential, high critical temperature.81) What is lean mixture in dual fuel combustion engine? (lean burn means the mixture of air and gas in the cylinder has more air than needed for complete combustion, reducing peak temp- less NOx, eff inc bcoz of higher compression ratio and optimsed injection timing.82) vit? Drawing of MCR pmax with load? Injection timing diagram with reference to tdc. Range? Tell me the injection timing of 50% load?

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83) What’s the time period to discard a chain and renew with new one in B&W tell the percentage elongation max allowed in 1 inch chain link? (max allowable limit of elongation is 1.2% , chains should be removed once in 8 yrs or 50,000 hours)84) Thrust pad removal? Diagram of front view along with retainer and top cover fitting screws? How do you remove pads? Where do you fix the tool? (reed’s vol. 8 pg 242)85) Exhaust gas of all units’ high cause? (bad quality fuel, faulty fuel system, poor scavenging)86) What is the purpose of lead screw and tool feeder? (lead screw for THREADING and tool feeder for TURNING)87) How will you weld two plates one of 16mm and one of 8 mm together in the same plane?88) CONSTRUCTION OF CHEMICAL TANKER AND PRODUCT TANKERS89) IS INERT GAS REQUIRED ON PRODUCT TANKERS? IF IT IS NOT PRESENT WHAT ARE THE OTHER ARRANGEMENT PROVIDED IN THE PRODUCT TANKERS? (YES, nitrogen purging)90) IS CHEMICAL TANKERS AND PRODUCT CARRIERS CAN CARRY DIFFERENT GRADES OF CARGO, IF CARRIED WAT R THE PRECAUTIONS TO BE TAKEN? WHAT ARE ARRANGEMENTS PROVIDED ON THE SUCH TANKERS? (crude tankers: different pumping arrangements for all the tanks and for chemical tankers every tank have different pumps, all tanks have different insulations)91) AS A 2ND ENGR. WHAT ARE THE PREPAREDNES FOR ISM SURVEY ONBOARD? (IMO SYMBOLS, D.P.A, SMS, DRILLS, TRAINING, CRITICAL EQUIPMENTS, CONTIGENCY PLANS, SAFETY EQUIPMENTS, P.M.S., NAVIGATIONAL EQ, BUNKERING PROCEDURES, POLLUTION PREVENTION PROCEDURES )92) BALLAST WATER MANAGEMENT? (pg-117, gautam sen)93) WHAT ARE CRITICAL EQUIPMENTS? (sudden operational failure of which may result in hazardous situation)94) LONG STROKE AND SUPER LONG STROKE ENGINES CONSTRUCTION DIFF. AND ADVANTAGES OF SUPERLONG OVER LONG STROKE. (super long adv is more time for scavenging and more air so more eff, less speed)95) MOMENT COMPENSATORS, HOW IT WORKS? (96) FUEL OIL INDEX NUMBERS? (97) WHAT IS CCAI NUMBER? (calculated carbon aromaticity index, 800-860 refer saif tole motor pg-13)98) SHORE SUPPLY 50 TO 60 Hz AND 60 TO 50 hz? (freq convertor)99) SHIP 'S LOAD TO INDUCTIVE LOAD, HOW TO IMPROVE POWER FACTOR? (put capacitor bank)100) VALENCE BAND? (Is the highest range of electron energies in which electrons are normally present at absolute zero temp.)101) DROOP SETTINGS AND ITS USES? (pg-265 sanyal)102) PARALLELING OPERATION OF GENERATORS? (103) Nomenclature of refrigerants? (R12, )104) how ll u rectify ovality of crankpin n how ll u run engine on this condition ( we will use oil stone to get the crank pin in the circular shape as far as possible. as with oval crank pin the oil film will not be proper and bearing though undersized will run hot. Lube pressure will be less. Then afterwards we use undersized bearing, if the engine has thick shell bearings same procedure with shims have to be put in, the oil pressure should never fall below 3.5 bars under full load condition.)105) DEWATERING system (provide draining and or pumping facility to pump out water from spaces which are located fwd of foremost cargo hold in case of detection inflow into corresponding spaces. Solas chapter 12 regulation 13.1. The sys task is to operate and supervise the operation of drainage sys by control and position indication of relevant butterfly valves in corresponding spaces. Spaces can be connected to educator for drainage and tanks r drained by ship water ballast system. Water lvl detector in hold at 0.5 mts and another on height not less than 15% or not more than 2mts)

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106) SPCV IN SULZER (spcv is stagnation pressure control valve used to suppress the after injection on RTA engines. If the SPCV is removed, the fuel pump is directly connected to the high pressure pipe allowing stagnation pressure to drop to a level where cavitations can occur.)107) WAT IS RATE SHAPING (108) Why AE NOX is less (time is very less for producing NOx as reaction time is less)109) what is tuned effect (B&W: the mark 5 series were introduced in 1991 and mark 6 series in 1993.man b&w engines with a mean effective pressure of 18bar and above come under the mark6 category . 1996-97 mk 7 engines introduced.110) As per solas define high speed craft, bulk carrier (high speed craft is a craft capable of a maximum speed in meters per second equal to or exceeding 3.7XV*0.1667 where V is volumetric displacement corresponding to the design waterline and BULK CARRIER means a ship which is constructed generally with single deck, top-side tanks and hopper side tanks in cargo spaces, and is intended primarily to carry dry cargo in bulk and includes such types as ore carriers and combination carriers)111) angle of loll (angle of loll: If ship is initially unstable, and the ship heels so much that the B comes under G, then GM is 0.so now the ship is inclined and in a kind of neutral equilibrium. now if the ship is further heeled, the ship rolls about this point .this is because on further heeling beyond loll angle, GZ becomes positive)112) The m/e t/c lub is supplied by m/e lo p/p, during sudden lub p/p failure how t/c is protected. (POST LUBRICATION TANK and lubrication system. During normal engine operation the post lubrication system is continuously filled by lube oil via a small bypass line from the m/e l.o. system that also supplies the t/c. Excessive ...l.o. is unpressurised supplied back to the m/e l.o. circuit bhy means of a free o'flow.In case of a shutdown or blackout of the m/e where the l.o. supply from the m/e to the t/c is interrupted, the l.o. flows down from the from the post lubrication tk by gravity, ensuring the lubrication and cooling of the two plain bearings during running out of the rotor for up to 20 mins. The m/e should be stopped within this time!! This system features 2 separate oil inlet pipes and 2 running down pipes with different levels from the post lubrication tk to the brgs. This ensures that in case of standstill of m/e and shut off l.o. supply that the turbine side brg is longer lubricated and cooled than the blower side brg. This tk is @ atmospheric pressure.)113) What is no volt coil? (Volt coil is used in trip ckt . this is energized by one phase and if there is any dip in the voltage then this coil is insufficiently energised and hence the breaker trips. OR no volt coil can also be used in starter, when handle is on ON position motor gets supply and entire starting resistance is series with armature and field. The current thru no volt coil energize it when handle is moved to run position, the no volt coil holds the handle by attracting the soft iron piece on the handle. Hence the no volt coil is also known as hold on coil. The no volt coil is designed in such a way that it holds the handle in run position only when sufficient current is flowing for which motor can run safely. If there is loss of load current drawn by motor decreases due to which it loses its required magnetism and release the handle. Under spring load it comes back to off position, protecting the motor from over speeding. Similarly if there is any voltage decrease then also no volt coil releases the handle. And in D.O.L. pg-70 mc.g )114) Skin effect (tendency of ac current to distribute itself within a conductor with the current densities being largest near the surface. Causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller thus reducing effective cross section of the conductor)115) why we use soft iron core in transformer (hysteresis loss reduces due to less residual magnetism)116) how bus bar is bolted (117) how will u check the O2 bottle supplied by the shore in large numbers if they are full or not (bottles are checked by radio isotopes or by weighing them...since u mention large numbers then radios isotopes s the best method...its similar to a laser gun used in checking temperatures)118) What is bumping clearance and what r its effect?119) What is bastard file? ( bastard file is a rough file bastard is the degree of roughness generally files are rough, bastard, smooth and super smooth)

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120) under which condition would u change the stuffing box spring (stuffing box spring should/can be changed 1) when from tel tel hole of individual unit of stuffing box lot of oil is coming and lube oil loss is there, u don’t have sealing ring, scrapper ring, or lamellas....so for time ...being u can change the spring. 2)when u completely overhaul stuffing box 3) when spring elongation is exceeded as per manual.....usually checked by hanging one kg weight at end new length -original length gies the elongation, check with manual for limits.....discard, replace with new one)121) What does the markings on the valve 5K-50 mean? (5k- 50 means a valve designed for 5 kg pressure and pcd is 50 mm)122) Why water drained from air bottle is milky white in color? (due to emulsion of water and oily)123) As per marpol annex II what is water performance test? ( pg275-276, annex 2, appendix 5)124) What type of welding are used 2 welds the anode to the hull & amp type of electrode? 125) What is gusset plate, stiller plate, docking bracket, swash bulk head n thr purpose. (pg-21/47 ship cons, stealer plate: a single wide plate which replaces two narrow plates in adjacent strakes of a ship plating/ the girth of the ship decreased toward the ends and so the width of the plates is also decresed in these parts. To save making the plates too narrow at the ends of the ship, it is usual to run a number of pairs of adjacent strakes into one. )126) what is required subdivision index and attained subdivision index127) Hw to determine if d rudder moves in port, the ship will also move towards port.128) in which portion of a cylinder liner bending occurs129) how to order grease130) what is d difference between pipe thread and bolt thread (pipe thread is bsp, less deep, lesser pitch and bolt thread is metric131) WAT IS AFRAMAX TANKER.EXACT DIFINITION. ( Aframax are ships with dwt b/w 80000 and 120000 and breadth over 32 mts. And the word afra means "average freight rate assessment"132) If chief officer says that cow machine is not working how will 2/e go about to convince him that it is working satisfactorily? ( There is an indicator on top of the cow machine which will show its operation. you can show him that OR you can do top wash. when u stand on the top of the tank i.e deck..the oils hits the inside top of the tank during top wash so when u stand on the deck u can feel it and make him convince that its all working fine)133) To which part of the ship is the pintle attached and how is it attached? is it fixed or is it floating with the rudder stock? ( pintle brg,refer reeds or taylor ship const OR pintle has a tapered face which matches the tapered surface of rudder arm and then bolted. Pintle rotates along with the rudder)134) Distance of the lubricating quills from top of the liner in terms of length of the liner.135) what are the safeties on air bottle (relief valve, bursting disc, pressure cut-out switch, low pr. Alarm)Mr. Sathpathy136) Cylinder lubrication, TBN how much it should be (HFO-70, LSFO-30-40)137) What all checks to be made on liner before giving it for survey (ovality, wear, surface condition, polishing, glazing, cracks)138) What causes ovality of liner (crosshead guideshoe and guide clearance)139) What is propeller law (a series of relationship for an installed power transmission sys which refers to shaft power, engine speed and mean effective pressure. These relationships place particle limits on engine designer. An engine under test and coupled to a dynamometer ll operate according to the propeller law.)140) What do we infer from Admiralty coefficient (reed’s naval arch-127)141) what are liner ribs and why they are in segments and use (provided at upper parts of liner to withstand combustion pressure and strengthening, in segments for freedom of coolant to flow)142) how piezo electric crystal looks (tetragonal crystals)143) why engine room valves lift is D/4144) what is the special construction of pedestal bearing on free end of rotor in auxiliary engine (margin for expansion)

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145) What is fitted bolt? How is it fitted? Where is it used? (Fitted bolts are used to connect rudder stock with rudder.( details refer naval arch alphi Delphi OR This is a closely fitted bolt. The holes are initially drilled to undersize and are reamed in the assembling place before the bolts are tightened in place. Accuracy is required in the machining. These bolts could be of two types one having ...a slight taper of about 1:100 on diameter and the other having a large taper of about 1:15 on diameter. However, the holes in either case are reamed in final place. Sometimes an oversized bolt is stretched hydraulically reducing the bolt diameter. When tightened down and the hydraulic pressure is released the final exact fit in the bolt hole is achieved, like a pilgrim nut on coupling shafts. These bolts find place in engine / boiler mountings, coupling shafts etc. and form a rigid fixture. On main engine mounting these are situated aft of the engine in the way of thrust block. OR interference bolt and fitted bolt are they same? What i have heard is fitted bolt dia and hole dia are the same. They are fitted by hammering. Interference bolt dia is slightly bigger than the hole dia and these bolts are fitted by hydraulic stretching and later bolted and the hydraulic pressure released.A waste gate arrangement is a valve in turbocharger that regulate amount of exhaust gases in the turbine side of tc diverting some of the exhaust gases directly in exhaust piping this will regulate the speed of tc and thus the compression ratio on the compressor side of tc. this is sometimes required in winter season as the air is cold thereby dense and less compression is needed as tc are designed on normal temp so this arrangement is sometimes there for winter season.146) What is VIT and super VIT. (Before the Super VIT was introduced variable injection timing was obtained by means of a special profile on the fuel pump plunger. Hence there was a fixed relationship between the injection timing and the fuel index. Thus it was not possible to adjust the fuel index of the individual pumps without also altering the injection timing. For this reason the Super VIT was introduced, where it is possible to adjust the fuel index and the injection timing independently In VIT beginning of injection could be controlled, but end of injection was fixed, due to profile of plunger n thus amount of fuel injected could not be changed with varying angle of injection at beginning. Thus MAN came up with super VIT where beginning n end both could be controlled by raising or lowering barrel in relation to plunger. Sulzer system when introduced vit way back in 80's it could control both beginning n end. Thus super VIT is for MAN B&W engines only147) What is the purpose of tst in bulk carriers? (For hatch coming support, for carrying ballast during ballast voyage.)148) What r the checks u would do on over board disc v/vs.?149) Why governor spring is conical? ( f=mw2r and f=kx so linear relation)150) What is a float free arrangement? (Float Free Arrangement is required on Emergency Position Indicating Radio Beacons (EPIRB) and life rafts. This allows the unit to float free and operate automatically if the vessel sinks. Units may still be able to be launched / released manually. Float-free launching is the method of launching a life raft whereby it is automatically released from a sinking ship and is ready for use. Float-free arrangements may either be an HRU or some other means. Whatever type it is, if your vessel capsizes too quickly for you to release the life raft manually the float-free arrangement may be your only chance of survival. A hydrostatic release unit used in a float free arrangement must have a Coast Guard approval number starting with 160.062. A float free link may be used with a Buoyant Apparatus or a Life Float and must be certified to meet 46 CFR, subpart 160.073151) wat is nitriding? (Nitriding is a heat treating process that alloys nitrogen onto the surface of a metal to create a case hardened surface. Three process are there for nitriding 1. gas nitriding 2. salt bath nitriding. 3. plasma nitriding.)152) explain how survey of rudder is done? how is the load of the rudder is transmitted to the ships hull? discuss about the stationary and moving cones? (pg 88 ship construction, wt of rudder acts down thru stock. This is supported by rudder carrier bearing. From stock load is transferred to pilgrim nut then to tiller then to distance piece, then to upper cone, then to base cone which is fixed to steering gear flat. upper cone is moveable & lower cone is fixed as it is attached to steering flat • rudder survey a. Visual examination of the rudder plating for cracks and distortion. Air plugs and drain plugs are to be opened in the presence of the class surveyor, repair superintendent and chief officer. Water draining out

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indicates a breached rudder and the breach to be located by air pressure testing and applying soap repairs to be planned. Check the rudder drop in the steering gear compartment (trammel gauge). Check the pintle clearances, jumping bar clearance and the palm coupling bolts tightness to be checked. Check the rudder stock for corrosion, erosion and any damage. The inspection plates in the way of the upper, the lower pintle to be cut open, and the pintle nuts checked for proper securing. Later the plates to be welded and tested. Hydraulic test the rudder for a static head of about 2.45m of sea water. After draining and re oiling the internals, plug the drain and check the effectiveness by a vacuum check and cement the plug. The rudder stock gland packing has to be checked and •153) what is the similarity and difference between a m/e governor and flywheel ( gov maintains speed of engine, flywheel controls cyclic fluctuation of engine rpm, flywheel works on virtue of inertia alone, govnr uses inertia to actuate fuel linkage to counter change in rpm)154) What is a thermal boiler? (In thermal boiler organic oils is heated in order to generate steam. This system is used in ships which carry cargo like bitumin n coaltar).155) What is a double stage evaporator boiler (turbine and auxiliary use)156) Draw the diagram(side-view) of an axial vibration damper for a MAN B and W engine (sanyal 157-158, leaf springs and oil chambers)157) Describe the items of a RO plant that require frequent overhaul and maintenance. How is sterilization carried out in it? (semi permeable membrane, acid addition, chlorination, u.v.sterlizers)158) What is a torsion meter? (it is a device to determine the torque or torsion in a shaft usually by measuring the twist in a calibrated length of shaft. )159) how will you avoid oil leaking from stern tube to sea( i think answer is by reducing the head of oil, by adding high viscosity oil, biodegradable oil)160) How high pressure pipes are manufactured? (seamless pipes )161) The classification societies accept a diminution of the chain thickness up to 11%. ( open joining shackle)162) how can we get a plate from lets say 16 mm thick two plate of equal dimensions just 8 mm thick plate ( is cutting from its thickness but then the question is how to cut? doesn’t want laser cutting : it could be done by heating the plate and passing thru rollers to reduce thickness and then cutting it into two equal) 163) What are persistent oils? What are its effects on marine environment? (persistent oils generally contain a large proportion of heavy fractions or boiling materials. Doesn’t dissipate rapidly)164) What is differential switch in crane? What are the safety features in crane other than limit switches? (braking, override controls, hydraulic oil high temp. alarm and trip, hydraulic oil tank low level alarm)165) Principle of wake (reed’s naval arch pg 137)166) Draw, how eta is attached to strong point in ship.167) draw, How bitts are welded on deck (bollards)168) When main engine is changed from do to hfo with rack at fixed position...whether speed increases or decreases...why? (speed ll increase)169) Draw over speed trip of a/e (170) Difference between air compressor valves and ref compressor valves171) How vertical centrifugal pump load is taken care? (double bearing  Crane Safeties:  1. Upper and lower limit switch for hoisting2. Jib max. and min. angle and rest position limit switch3. Differential limit switch between luffing and hoisting (to keep a minimum distance between jib top and hook block, irrespective of jib angle)4. Slewing limit switch (not for 360deg full slewing type)

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5. Slack limit switch for hoisting rope (to protect the hoisting ropefrom irregular winding or slackening, hoisting device stops automatically by the limit switch)6. Interlock switch for control handles (to prevent misoperation, when starting and restarting the crane after the limit sw are acted)7. Overload protector fm hydraulic parts ie relief valve (one each for hoisting n luffing and usually two for slewing, one for clockwise, second for anti clockwise)8. Resistance thermometer sensor for oil cooler9. Oveccurrent protector for induction motor10. Low level switch for oil tank11. Jib emergency limit switch (to stop the jib motion if due to sticky or smthin the luffing ckt is malfunctioning)   36. What is EEDI?Energy Efficiency Design Index (EEDI) is an attempt to measure how much CO2 a ship emits per unit of transport provided. A formula producing an EEDI for each ship is developed. The current EEDI formula is outlined in MEPC.1/Circ.681, Interim Guidelines on the Method of the Calculation of the Energy Efficiency Design ...Index for New Ships, 2009-08-17. Then an upper limit on EEDI is mandated for all new buildings. In most variants, this upper limit drops through time.The amendments to MARPOL Annex VI Regulations for the prevention of air pollution from ships, add a new chapter 4 to Annex VI on Regulations on energy efficiency for ships to make mandatory the Energy Efficiency Design Index (EEDI), for new ships, and the Ship Energy Efficiency Management Plan (SEEMP) for all ships. Other amendments to Annex VI add new definitions and the requirements for survey and certification, including the format for the International Energy Efficiency Certificate.The regulations apply to all ships of 400 gross tonnage and above and are expected to enter into force on 1 January 2013.However, under regulation 19, the Administration may waive the requirement for new ships of 400 gross tonnage and above from complying with the EEDI requirements. This waiver may not be applied to ships above 400 gross tonnage for which the building contract is placed four years after the entry into force date of chapter 4; the keel of which is laid or which is at a similar stage of construction four years and six months after the entry into force; the delivery of which is after six years and six months after the entry into force; or in cases of the major conversion of a new or existing ship, four years after the entry into force date.The EEDI is a non-prescriptive, performance-based mechanism that leaves the choice of technologies to use in a specific ship design to the industry. As long as the required energy-efficiency level is attained, ship designers and builders would be free to use the most cost-efficient solutions for the ship to comply with the regulations.  

The SEEMP establishes a mechanism for operators to improve the energy efficiency of ships.Promotion of technical co-operationThe new chapter includes a regulation on Promotion of technical co-operation and transfer of technology relating to the improvement of energy efficiency of ships, which requires Administrations, in co-operation with IMO and other international bodies, to promote and provide, as appropriate, support directly or through IMO to States, especially developing States, that request technical assistance.It also requires the Administration of a Party to co-operate actively with other Parties, subject to its national laws, regulations and policies, to promote the development and transfer of technology and exchange of information to States, which request technical assistance, particularly developing States, in respect of the implementation of measures to fulfill the requirements of Chapter 4. 

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  Dry Dock Chain Inspection  Anchor & Anchor Chain CableAnchors and anchor chain cable if ranged should normally first be examined as follows:Anchor heads, flukes and shanks should be surface examined for cracks. If any such defects are found they may be weldable, otherwise renewal will probably be necessary. In such cases welding may be ...attempted as a temporary measure pending availability of the new equipment, which may take 3 to 6 months.Anchor head crown pins and anchor shackle pins should be hammer-tested, hardened-up if slack, or renewed if excessively worn or bent.Swivels if fitted, should be closely examined so far as possible in way of the threaded connection, as many have been lost in service due to concealed wastage in this area. If in doubt the swivel should be recommended to be removed. Consideration should be given to simply eliminating any questionable swivels, they are normally not essential.Patented type detachable connecting links should be opened out and slack or corroded taper locking pins renewed their holes re-reamed and new lead keeper plugs peened in."U" type connecting shackles should be examined for excessive neck wear, slackness in the pins and for shearing of keeper pins. The pin must be a snug fit all around in these shackles, otherwise the keeper pin may shear when a strain is put on the chain.Anchor chain cable should be surface examined, hammer-tested and loose or missing studs replaced by welding at one end of the stud only, at the end of the stud opposite the link butt weld. The rest of the chain cable should be further examined for excessive wear and gauged if necessary to ensure continued compliance with the Rules.Verify that the number of shots of anchor chain as fitted port and starboard, equal the total length required by the Classification Rule Equipment Numeral.     Differences between MC/MC-C and ME/ME-C engines  The electrohydraulic control mechanisms of the ME engine replace the following components of the conventional MC engine:• Chain drive for camshaft• Camshaft with fuel cams, exhaust cams and indicator cams...• Fuel pump actuating gear, including roller guides and reversing mechanism• Conventional fuel pressure booster and VIT system• Exhaust valve actuating gear and roller guides• Engine driven starting air distributor• Electronic governor with actuator• Regulating shaft• Engine side control console• Mechanical cylinder lubricators.The Engine Control System of the ME engine comprises:• Control units• Hydraulic power supply unit• Hydraulic cylinder units, including:• Electronically controlled fuel injection, and• Electronically controlled exhaust valve activation• Electronically controlled starting air valves• Electronically controlled auxiliary blowers• Integrated electronic governor functions• Tacho system

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• Electronically controlled Alpha lubricators  flash blowdown of a boiler

BOILER BLOWDOWNEven with the best pretreatment programs, boiler feedwater often contains some degree of impurities,such as suspended and dissolved solids. The impurities can remain and accumulate inside the boiler asthe boile...r operation continues. The increasing concentration of dissolved solids may lead to carryoverof boiler water into the steam, causing damage to piping, steam traps and even process equipment. Theincreasing concentration of suspended solids can form sludge, which impairs boiler efficiency and heattransfer capability.To avoid boiler problems, water must be periodically discharged or “blown down” from the boiler tocontrol the concentrations of suspended and total dissolved solids in the boiler. Surface waterblowdown is often done continuously to reduce the level of dissolved solids, and bottom blowdown isperformed periodically to remove sludge from the bottom of the boiler.The importance of boiler blowdown is often overlooked. Improper blowdown can cause increased fuelconsumption, additional chemical treatment requirements, and heat loss. In addition, the blowdownwater has the same temperature and pressure as the boiler water. This blowdown heat can be recoveredand reused in the boiler operations.Boiler Blowdown Benefits• Less water, fuel and treatment chemicals needed;• Less maintenance and repair cost (minimized carryover and deposits);• Saves manual supervision for other tasks (with automatic control);• Cleaner and more efficient steam;• Reduced operating cost (reduction in consumption, disposal, treatment and heating of water);• Minimized energy loss from boiler blowdown can save about 2 percent of a facility’s totalenergy use with an average simple payback of less than one year.Flash Tank SystemThe flash tank system shown in the figure below can be used when expense and complexity must be reduced to aminimum. In this system, the blowdowns from the boilers are sent through a flash tank, where they are converted intolow-pressure steam. This low-pressure steam is most typically used in deaerators or makeup water heaters.see diagrams on post dated 3-02-2011 by me(felix pinto)Flash Tank – Heat Exchanger SystemThe system shown below consists of a flash tank and a heat exchanger. The temperature of the blowdown leaving theflash tank is usually still above 220°F. The heat of this flash blowdown can be used to heat makeup water by sending itthrough the heat exchanger, while cooling the blowdown at the same time. Heating boiler makeup water saves on fuelcosts. An additional advantage of cooling blowdown is in helping to comply with local codes regulating the discharge ofhigh temperature liquids into the sewer system.  Catalytic FinesCatalytic FinesOrigin:By-product from the catalytic cracking process in the refinery

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Catalyst consists of complex crystalline particles containing aluminium silicate... Catalyst fines result from catalyst particles breaking into smaller particlesCatalyst is expensive, i.e. refiners minimise loss but not 100%  Effects* Severe wear of Liners* Severe wear of Rings* Wear out of Cyl-grooves* Scuffing of liner* Abrasive Wear of Spindle-Guide & cut-off shaft & nozzles* Scuffing of Fuel Pump spindle guide  SpecificationVariable in size ranging from sub microic to about 30 microns – even seen largerFrequently considered spherical but this is not necessarily the caseHard particlesHardness not directly related to relative hardness of Al or SiCan cause abrasive wearISO 8217 specifies the catalyst fines by Al and SiISO 8217 limit is 80 mg/kg Al+Si for marine residual fuels  (Note: ISO 8217 limit is for bunker not at engine inlet)  ReductionGravitational settlingCentrifuge(Note: Homogenisers will not reduce the amount of catalyst fines but might insteadbreak them into even smaller particles)Overhaul and maintenance intervals must be kept according to manufacturersrecommendationTemperature control very important  The higher the temperature the better the separation efficiency. Both densityand viscosity of the oil decrease when the temperature rises, therebyincreasing the settling velocity (Stoke’s law)(If the separation temperature is lowered from 98ºC to90ºC the separator throughput has to be reduced by25-30% to maintain the same separation efficiency!!)   CRANK CASE INSPECTION (20 points)1. Firstly check the oil condition for any smell,discolouration or degradation.2. Turn the Engine to BDC & start checking from under stuffing box area for any signs of black oil, if so in...dication of stuffing box leaking.3. Check piston rod surface for scoring marks & roughness.4. Check Piston palm bolts & locking device for slackness & fretting.5. Check guide & guide shoe bearing general condition & area around frame where guide is attached for any visible cracks.6. Check guide shoe end cover bolts in place & not slack.7. Check cross head general bearing condition.8. Top & Bottom end of the con rod bolt, nut & locking devices for slackness,sign of fretting etc.9. Check sliding of bottom end bearing (floating of con rod).

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10. Check for slip of web & journal by checking the reference mark.11. Check the web in the area of stress concenteration & check tie bolts (bottomside).12. Check cross girder , area around main bearing & bearing keep for signs of cracks & check the main bearing.13. All bearings to be checked for silvery colour, (indicates bearing wiping)14. Check all the surrounding oil pan area of all units for any sludge deposits, bearing metal pieces etc.15. Check crankcase releif door (wire mesh should be wet, spring tension sealing condition etc.)16. Check the teeth of transmission gears for signs of wear.17. Check chain drive for tightness.18. Oil mist detector sampling pipe to be checked for clear passage.19. Clear all foreign materials from the C.C. & tools accounted for.20. Start L.O.p/p & X-Hd p/p & check oil flow & distribution.21Check C.C.door sealing condition & close the door.  BABBITTING is a process by which relatively soft metals are bonded chemically or mechanically to a stronger shell or stiffener, which supports the weight and torsion of a rotating, oscillating, or sliding shaft. The babbitt, being softer than the shaft and... having excellent antifrictional qualities, prevents galling and/or scoring of the shaft over long periods of use. Compositions and selected properties of babbitts are summarized in Tables and and Fig.. Babbitting is named for Isaac Babbitt, who patented the process in the United States in 1863. Babbitt metals, which are more widely known as white metals, are comprised principally of tin alloys (hardened with copper and antimony) or lead alloys (hardened with tin and antimony and, in some cases, arsenic). In the babbitting process, the relatively soft bearing material (babbitt) is bonded to a stronger supporting base metal, typically mild steel, cast iron, or bronze. The base metal may be in the form of mild steel strip unwound from a coil, a half-round mild steel pressing or bushing, or a bronze or iron casting. The bonded bimetal material is shaped and machined to make plain, fluid film lubricated bearings for a wide variety of automotive, industrial, and marine applications. Babbitt is used in small bearings for high-volume applications, such as electric motors and internal combustion engines, and for large rotating and reciprocating machinery with low to modest volume requirements, such as high-speed turbines and low-speed marine diesel engines. In addition, babbitt has been used for jewelry, shot, filler metals, and various other applications. Lead-base alloys enjoy a cost advantage, while tin alloys offer modest technical advantages, particularly in high-speed centrifugal equipment. It should be noted that government regulations now discourage the use of lead-base alloys for health and hazardous waste disposal reasons. Babbitting of bearing shells can be accomplished by three methods: Static babbitting (hand casting) Centrifugal casting Metal spray babbitting Centrifugal casting and static (gravity) casting are the two babbitting methods used in the manufacture and repair of large, low-volume journal (radial) and thrust bearings. Centrifugal casting of journal bearings offers both technical and economic advantages if special spinning equipment is available. Flat shapes (thrust bearings) are usually statically cast. Repairing of industrial and marine babbitted bearings is routinely accomplished by melting off the old metal and rebabbitting the shells with new metal, following the same basic casting methods described below for producing new products. Emergency repair methods using proprietary tinning compounds, babbitt spray, or welding techniques can be employed. Suppliers of such repair equipment should be consulted for operating instructions. Thin-wall babbitted half bearings, rolled bushings, and flat thrust washers are mass produced from bimetal strip stock. The strip stock is produced by continuously feeding coils of low-carbon steel in ribbon form first through appropriate cleaning and tinning baths and then through a stream of molten babbitt, which is gravity cast on the moving strip. The strip is immediately water-chilled from below. After excess babbitt is removed, the stock is recoiled and is ready for press blanking, forming, and finish machining operations. Details of mass production methods for making babbitted bearings are proprietary to the manufacturers involved, and beyond the scope of this article. 

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PROPELLER SHAFT & RUDDER STOCK STRAIGHTENINGLarge diameter shafts, such as, for example, propellor shafts, rudder stocks etc. are subject to bending which can occur during manufacturing, processing or in subsequent use. Such bending can occur in th...e rough forging of the shaft and when machining to final dimensions. In lively forgings the final cut for a keyway or the like can create bends. Under some circumstances, such shafts will become bent after period of use or if a propellor, for example, strikes an obstruction. Acceptable limits of bend or eccentricity have been established and as a norm, a permissible eccentricity has been established at 7.4 thousandths of an inch for some operational uses. Above such a figure, mechanical and technical difficulties arise.Heretofore, methods for the straightening of shafts have been devised including a "hot spot" method and a "peening" method.  The hot-spot method involves quickly heating a local spot (on the outside of a bend) to an elevated temperature. As a result of the local heat, the heated region tends to expand, but also due to the elevated heat, the yield strength of the material is reduced. Due to these combined effects, the metal yields such that the shaft bulges slightly in the heated region. When the heat is removed, the metal then hardens and remains in the bulged position and the residual tensile stresses introduced into the outside of the bend of a shaft tend to straighten the shaft. The hot-spot method is characterized by the following intrinsic disadvantages:1. The heating process is not accurately controllable. There is no precise method of determining the amount of heat applied to the shaft.2. The metallurgy of the shaft can be adversely affected.3. The process is extremely slow; after each heating the entire shaft must be allowed to cool to a uniform temperature before the results can be assessed.  With the peening method, a hammer or equivalent technique is used to hammer or peen the shafting surface on the inside of a shaft bend. The residual compressive stresses thereby introduced into the shaft tend to straighten the shaft. The peening method entails the following intrinsic disadvantages:1. The magnitude of the peening effort required to straighten shafts of large diameter, especially those of high tensile strength, exceeds that which can be accomplished with the usual peening techniques.2. The residual stresses introduced into the shaft are distributed non-uniformly.3. Peening subjects the shafting surface to possible damage.4. Due to the superficial nature of the compressive residual stresses introduced, efforts to improve the surface finish of the shafting after peening by cutting a small amount of metal from the shaft will tend to destroy the effect achieved because the residual stresses in the metal removed from the shaft will not be uniform around the circumference of the shaft.  The selective cold rolling method involves the use of cold rolling equipment such as is commonly used in connection with propellor shafts & rudder stocks on ships, however, instead of using a constant roller load and introducing residual compressive stresses uniformly around the circumference of a shaft, the roller load is varied selectively so as to use a higher roller load, with consequent higher residual compressive stresses, on the inside of a bend thereby tending to straighten the shaft. The selective cold rolling of a shaft is accomplished by pressing a small roller against the shaft with alternating loads as the shaft is slowly rotated. A specified length of the shaft is rolled by slowly advancing the roller along the shaft as it rotates.The roller has a crowned face and is sized with radii of curvature which are much smaller than those of the shaft such that a very small elliptical contact area exists between the roller and the shaft. The combination of a heavy roller load on the shaft and the small contact area results in very large contact stresses between the shaft and roller. These stresses cause a yielding of the shaft material near the surface which then leaves a residual compressive stress in the material adjacent to the surface. By controlling the roller load, the magnitude and depth of the residual stress can also be controlled. The residual stress over

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the yielded depth actually produces a residual force in the area adjacent to the shaft surface and it is this residual force which is utilized to straighten a shaft.  Advantages associated with the selective cold rolling method include the following:1. The variables required to straighten a shaft can actually be calculated.2. The method is easily controlled such that predictable results can be achieved.3. The residual stresses introduced in the shaft are not distributed erratically.4. The results achieved can be assessed immediately after a rolling operation.5. The straightening can be accomplished by introducing residual compressive stresses completely around the shaft circumference but more deeply on one side of the shaft than the other; this permits a small amount of metal to be removed from the shaft without affecting the straightening results achieved.6. The metallurgy of the shaft material is not adversely affected.  How to "flash" a generator when output is lost due to loss of excitation  Residual magnetism in the generator exciter field allows the generator to build up voltage during start-up. This magnetism is sometimes lost due to shelf time or improper operation, among other reasons. Restoring this residual magnetism is possible and is sometime...s referred to as "flashing the exciter field".  To restore the small amount of residual magnetism necessary to begin voltage buildup, connect a 12 volt battery to the exciter field while the generator is at rest, as follows:  Remove exciter field leads F+ and F- from the voltage regulator. CAUTION: Failure to remove the field leads from the regulator during flashing procedures may destroy the regulator.Measure the exciter field resistance from the F+ to the F- lead. You should be able to read some resistance as you are measuring a continuous winding. An infinite resistance reading would indicate an open in the exciter field. Also check to be sure there is no path to ground.Connect F+ to the positive pole of the battery.Hold the F- lead by the insulated portion of the lead wire, touch F- to the negative pole of the battery for about 5 to 10 seconds, then remove.Reconnect F+ and F- to the regulator. Repeat the procedure if the generator fails to build voltage. CO2 system Maintainence :  *** weekly**** CO2 release box to be opened up - will give alarm & in some ships blowers may trip....* Check CO2 release alarms* There are 2 master cyliders in the release boxcheck their - pressure ; securing arrangement ; piping  Checks in CO2 room  * make sure that vent is open* open the door - once the door opens blowers must start* Allow for ventilation & then enter inside* Check the 2 pilot, master & bank of cylinders for secure location* Pipe connection between the cylinders & main header to be checked for crack or slackness* Feel each cylinder by hand ; if cylinder leaks it will be cold* Check the bursting disc for each cylinder to be in good condition

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* Check the pilot cylinder pulleys -n free & greased* Check the pulling wires - greased & no slackness , no strands broken* Check lighting in CO2 room* Main CO2 v/v to E/R - hand operate to ensure it's free usually pneumatically operated* Co2 room is insulated , check it's insulation* Check the temp. of the room