Unit 96: Marine Propulsion Power Plant

Transcription

1 Unit 96: Marine Propulsion Power Plant Unit code: R/503/1756 QCF Level: 5 Credit value: 15 Aim This unit provides learners with an understanding of marine propulsion power plant. Learners will also gain an understanding of maintenance procedures for marine propulsion power plant. Unit abstract This unit covers three ship power plant systems; marine turbines, marine diesels and marine electrical motors. Learners will explore the construction and performance characteristics of marine turbines. Learners will understand marine diesel engines in relation to efficiency, mechanical and thermal stresses, engine timing and designs to limit pollution. This unit introduces learners to marine electrical propulsion power plant including the operation of AC/DC motors and electronic speed control. Learners will explore harmonic analysis and interference suppression encountered with thyrister-based speed controllers. This unit also covers maintenance procedures for marine propulsion power plant. Learning outcomes On successful completion of this unit a learner will: 1 Understand marine turbine power plant 2 Understand marine diesel engines 3 Understand marine electrical propulsion power plant 4 Understand maintenance procedures for marine propulsion power plant 1

2 Unit content 1 Understand marine turbine power plant Turbine machinery: construction and operation; impulse and reaction turbines; pass-out and back pressure; condensers; single and twin spool gas turbines; regeneration Performance characteristics: Carnot and Rankine cycle efficiencies; isentropic efficiency; power output; use of steam tables and enthalpy-entropy diagrams Auxiliary systems: steam systems; main feed system and feed water tests; turbo driven auxiliary machinery and gland sealing; gas turbine auxiliary systems; air, fuel and oil systems; glands and sealing arrangements; free power turbines; primary gearboxes; Engine Health Monitoring (EHM); start /stop routines 2 Understand marine diesel engines Efficiency of marine diesel engines: power to weight ratios; two and four stroke engines; fuel consumption; turbo-charging; waste heat recovery Mechanical and thermal stresses: materials (selection and use); relative sizes and dimensions; stress reversal and fatigue failure; thermal stressing eg environmental and generated thermal conditions, exposure to high and low temperatures Engine timing and combustion: camshaft drives and cams; reversing; fuel pumps; injectors and valves; air start systems Designs to limit atmospheric pollution: engine design eg cross-head, trunk piston; fuel oil injection methods; exhaust gas re-circulation; homogenisation; direct water injection; water mist; exhaust gas scrubbers; catalytic reduction 3 Understand marine electrical propulsion power plant Electrical propulsion motors: AC and DC motors; characteristics eg torque, speed, efficiency; three-phase rotating magnetic field; induction and synchronous motors; stator and rotor construction; synchro drives Motor starters: AC and DC; starters eg manual and automatic direct on-line, star-delta, autotransformer, soft starting; motor failure eg short circuit, single phasing, bearing failure, overheating, stalled load; protection systems eg short-circuit, over-current, differential protection, thermistor Speed control: AC and DC motors; PWM converters; power electronics hardware eg DC choppers, controlled rectifiers, cycloconverters, static frequency changers, dynamic breaking resistors Interference suppression: harmonic analysis; suppression techniques eg passive filters, active filters, snubbers 2

3 4 Understand maintenance procedures for marine propulsion power plant Maintenance procedures: planned maintenance eg running hours, application of maintenance schedules, use of manufacturers guides and manuals, expected and projected life of components; repair and breakdown maintenance Maintenance implementation: permit to work; risk analysis; availability of human and physical resources; downtime Planned maintenance: approved planned maintenance system eg statutory requirements, ship type, owner requirements; coordinating maintenance with dry docking schedules and off hire periods Safety precautions: hazards eg high voltage, gearboxes, gearing, shafting, lub oil systems 3

4 Learning outcomes and assessment criteria Learning outcomes On successful completion of this unit a learner will: 1 Understand marine turbine power plant 2 Understand marine diesel engines 3 Understand marine electrical propulsion power plant 4 Understand maintenance procedures for marine propulsion power plant Assessment criteria for pass The learner can: 1.1 summarise the operating principles of turbine machinery used for marine propulsion power plant 1.2 analyse the performance characteristics for marine turbine propulsion power plants 1.3 describe the construction and operation of auxiliary systems in marine turbine propulsion power plant 2.1 analyse the efficiency of marine diesel engines 2.2 explain how to limit mechanical and thermal stresses in diesel engines 2.3 evaluate methods of timing the diesel engine and how this affects the combustion process 2.4 evaluate marine diesel engine design to limit atmospheric pollution 3.1 explain the operating characteristics of marine electrical propulsion motors 3.2 explain the operation of motor starters and protection systems 3.2 compare speed control hardware for electrical propulsion motors 3.4 evaluate harmonic analysis and interference suppression methods used in power electronic hardware 4.1 explain the need for maintenance of marine propulsion power plant 4.2 evaluate how the maintenance for marine propulsion plant is planned and implemented 4.3 explain how planned maintenance for marine propulsion plant relates to statutory, class and owner requirements 4.4 describe the appropriate safety precautions to use when undertaking maintenance of marine propulsion power plant 4

5 Guidance Links This unit is designed to be stand alone but it has links to the following Higher National units: Unit 4: Mechanical Principles Unit 6: Health, Safety and Risk Assessment in Engineering Unit 50: Condition Monitoring and Fault Diagnosis Unit 61: Engineering Thermodynamics Unit 68: Applications of Power Electronics Unit 94: Marine Electrical Systems Unit 95: Ship Propulsion and Manoeuvrability. Essential requirements There are no essential requirements for this unit. Employer engagement and vocational contexts Centres delivering this unit should possess, or have access to, a wide range of marine power plant. Visits to engineering departments in large ships could be used to reinforce the learning outcomes of this unit. Engagement with ship staff (marine engineering) will help with the delivery and assessment of this unit. 4869dm090611S:\LT\PD\High Nationals 2010\MARINE ENG single units for web\unit 96 BH Marine Propulsion Power Plant-Sc3.doc\1-5/0 5