290 likes | 683 Views
FUEL INJECTOR. CYLINDER HEAD. Engine Construction Stationary Parts 2 s/c Slow Speed. EXHAUST VALVE. JACKET WATER. EXHAUST MAINIFOLD. CYLINDER LINER. INTAKE MAINIFOLD. CYLINDER BLOCK. INTAKE PORTS. CRANK CASE. A FRAME. BEDPLATE. LUBE OIL SUMP.
E N D
FUEL INJECTOR CYLINDER HEAD Engine ConstructionStationary Parts2 s/cSlow Speed EXHAUST VALVE JACKET WATER EXHAUST MAINIFOLD CYLINDER LINER INTAKE MAINIFOLD CYLINDER BLOCK INTAKE PORTS CRANK CASE A FRAME BEDPLATE LUBE OIL SUMP
Engine ConstructionMoving Parts2 s/cSlow Speed TURBO-CHARGER PISTON PISTON ROD INTER- COOLER CROSS HEAD GUIDES CROSS HEAD CRANK CASE CONNECTING ROD CRANK SHAFT CRANK PIN WEB CRANK SHAFT BEARING
ROCKER ARM VALVE ACTION PUSH ROD CAM SHAFT CAM
FUEL PUMP OTHER CAMS FUEL CAM
MAX CAM LIFT INJECTION ENDS INJECTION BEGINS FUEL CAM ENGAGES FUELPUMPACTION FUEL SUPPLY FUEL RETURN Effective Stroke Cam Lift
INJECTION BEGINS FUEL CAM ENGAGES FUELPUMPACTION FUEL SUPPLY FUEL RETURN Effective Stroke • To affect engine power and/or speed • Vary effective stroke • More/less fuel to cylinder during power stroke Cam Lift
INJECTION BEGINS FUEL CAM ENGAGES FUEL DELIVERED per PWR STROKE To affect engine power and/or speed– vary effective stroke • ROTATE plunger • Injections begins as before • ,,, but ends earlier • Less fuel per power stroke • Power/speed is reduced Effective Stroke
The are many fuel injection arrangements… • Fuel pumps may be mounted on injector (unit injectors) and activated via a rocker arm from above—or an “overhead cam” • Fuel pumps may be activated electrically, timed with a microprocessor (no fuel cam—electronic injection) • Fuel may be delivered a constant high pressure to injectors and the injector activated mechanically or electronically at precisely the right moment
… but ALL fuel injection systems must satisfy the following requirements • Accurate METERING • Proper TIMING • Suitable INJECTION RATE • Clean CUT-OFF • Adequate ATOMIZATION • Sufficient PENETRATION
FUEL SYSTEM(Slow Speed Diesel Propulsion SUPPLY RETURN HP FILTER F.O. PURIFIER VISCOSIMETER DAY TANK No.2 DAY TANK No.1 V FO SERVICE PUMP HTR DB TANK LP FILTER
CYLINDER OIL Lube Oil System(s) METERING PUMP HP FILTER CIRCULATING SYSTEM LO STORAGE L.O. COOLER L.O SERVICE PUMP LP FILTER L.O. PURIFIER
L.O. CLR AIR CLR EVAP “CENTRALIZED COOLING”(LS Diesel Propulsion) LTFW HTFW Sea Water FW CLR JACKET WATER JW CLR SW CIRC PUMP FW CIRC PUMP JW PUMP
THERMOSTAT T FUEL PUMPS L.O. CLR J.W. PUMP Medium Speed Engines J.W. COOLER AIR CLR L.O. PUMP F.O. SERV. P. Return
M Diesels are not self-starting… Smaller Medium & High Speed engines are started via a MOTOR engaged to a flywheel e.g., ELECTRIC MOTOR START Start switch BATTERY FLYWHEEL
M Start valve Diesels are not self-starting… Smaller Medium & High Speed engines are started via a MOTOR engaged to a flywheel or AIR MOTOR START AIR RECEIVER ≈ 120 psi STARTING AIR COMPRESSOR
Start valve M Diesels are not self-starting… Smaller Medium & High Speed engines are started via a MOTOR engaged to a flywheel or HYDRAULIC MOTOR START ACCUMULATORS ≈ 3000 psi RESERVOIR
Larger Medium Speed & Slow Speed engines areDIRECT AIR START STARTING AIR VALVE To other cylinders PILOT VALVES STARTING AIR RECEIVER 300-500 psi • STARTING AIR admitted during POWER STROKE until engine fires • STARTING AIR may be used to brake engine once fuel is cut off SAC