Synergy Quiz Btech Welcome to your Synergy Quiz btech 1. Precision engine bearing inserts are manufactured with a small portion of the bearing ends extending beyond the bearing housing or caps. The installation process of these bearings requires sufficientoverlapcrushlap or leadprotrusion 2. The method of piston cooling in which oil is delivered through the connecting rod to a compartment within the piston, then distributed by the motion of the pistons, and allowed to drain to the crankcase via one or more holes or pipes, is termedquakershakercirculationspray 3. The piston rod scraper box incorporated in a two-stroke/cycle, crosshead diesel engine serves toeliminate the necessity for an oil scraper ringprevent side thrust and cylinder scoringprevent sludge and dirty oil from entering the crankcasescrape oil and carbon deposits off the cylinder walls 4. In a large, slow-speed, main propulsion diesel engine, which of the parts listed is under tension when the engine is running?Bed plateColumnEntablatureTie rod 5. The main advantage of unit injectors (combined fuel pump and injector) over other fuel injection systems isthe lack of high pressure fuel linestheir relatively low injection pressuresreduced wear of spray orificesthe lessened chance of fuel leaks into the engine sump 6. Passages are drilled in the crankshafts of diesel engines to provide lubricating oil to themain bearingsconnecting rod bearingspiston pin bushingsAll of the above 7. When may the crankcase ventilation pipes or oil drain pipes of two or more engines be connected?Propulsion engines under 1000 shaft horsepower may share a common crankcase vent provided the oil drains remain separate.In most cases it is desirable and cost effective for propulsion engines to share a common crankcase ventilation and monitoring system.No interconnection may be made between the crankcase ventilation pipes or oil drain pipes.None of the above are correct. 8. The main function of tie rods in the construction of large, low speed diesel engines is tostiffen the bedplate in way of the main bearings to increase the engine's longitudinal strengthaccept most of the tensile loading that results from the firing forces developed during operationmount the engine frame securely to the hull to prevent shaft coupling misalignmentconnect the crosshead solidly to the piston rod 9. On most modern diesel engines, the main and connecting rod bearings receive their lubricating oil bybanjo feedsplash feedgravity feedpressure feed 10. Fuel injection pumps using the port and helix metering principle requires the use of acrosshatched designlapped plunger and barrelvariable strokevariable cam lift 11. Lubricating oil is supplied to the crankpin bearings in a marine diesel engine byinternal crankshaft passagesimmersion in oilspclearance lubricationinjection lubrication 12. gudgeonpin bearings are difficult to lubricate because of their oscillating motion andtheir free-floating designtheir relatively small sizethe reciprocating motion of the pistontheir position in the lubrication system 13. The camshaft drive is designed to maintain proper camshaft speed relative to crankshaft speed. In maintaining this relationship, the camshaft drive causes the camshaft to rotate atone-half crankshaft speed in a two-stroke cycle diesel enginecrankshaft speed in a two-stroke cycle diesel enginetwo times crankshaft speed in a two-stroke cycle diesel engineone-fourth times crankshaft speed in a four-stroke cycle diesel engine 14. Engines having a bore exceeding 250 mm, but not exceeding 300 mm are to have at leastthree compression rings per piston and the minimum of two oil scraper ringsone intake and one exhaust valve per cylinder provided no other means of scavenging is usedone explosion relief valve in way of each alternate crank throw, with a minimum of two valvesone crankshaft except in cases where an opposed piston design is required 15. The opening of an exhaust valve on a modern, large, low- speed, main propulsion diesel engine, may be actuated bydirect action of cam shaftcompressed air pressurehydraulic "push rods"direct action of the main piston moving down 16. Shaker, circulation, and spray are the three general methods used inpre-injection fuel oil treatmentlube oil filtrationlube oil purificationpiston cooling 17. The speed of the camshaft in a two-stroke/cycle diesel engine, running at 950 RPM, is475 RPM950 RPM1900 RPM2400 RPM 18. Explosion relief valves on diesel engine crankcases should relieve the pressure at not more than0.1 bar0.2 bar1.0 bar2.0 bar 19. A two stroke diesel engine exhaust temperaturewill be lower than a four stroke diesel engine of the same displacement because the ___________. I. scavenging air is cooling the exhaust gases II. exhaust cycle time is longerI onlyII onlyboth I and IIneither I nor II 20. The sealing surfaces of a diesel engine piston ring are considered to be the faces in contact with the cylinder wall, in addition to the ring groove ___________.bottombacktopside Time is Up!