Course Topics
- Design Features and Operating Mechanisms of MDE
- Theoretical Cycles Internal Combustion Engines
- Basics of Diesel Engines
- Cycle, Timing Diagrams
- Types of diesel engines
- Introduction to some modern engines
- Basic UMS Operation of ME-Engine Block Diagram
- Constructional features of DE
- Two stroke
- Cylinder Cover, Mountings
- Exhaust Valves
- Cylinder Liner, Piston
- Liner
- Basic Construction and Working of Piston
- Piston Crown and Piston Rings
- Crosshead, Connecting Rod
- Stuffing Box
- Crankshaft
- Crankshaft (2)
- Chain drives
- Operation and Inspection of Chain Drives
- Damages in Chain Drives and the Ways to Rectify it
- Measurement of Chain Drives
- Bearings
- Crosshead Bearings
- Bottom-End (Crankpin) Bearings
- Main Bearing
- Main Bearing (2)
- Lubrication of Bearings
- Bearings (2)
- Clearance measurement
- Bearing's
- Camshaft
- Fuel Pumps
- Tie Rods
- Four stroke
- Why 4-stroke
- Auxiliary Engines
- Wartsila Engines
- MAN Vee-Type Trunk Piston Engines
- Four Stroke diesel Engines
- Exhaust Valves (2)
- Trunk Piston Engines
- Steam Propulsion (conventional)
- Types of Steam Turbine
- Marine Gas Turbines
- Gas Turbine
- How Gas Turbine works
- Gas Turbine Performance
- GT Constructional Features
- GT Auxiliary Equipment
- GT in today's marine industry
- Gas Turbine Engine
- Nuclear fueled steam propulsion
- Electrical Propulsion
- COGES-Co generation - propulsion system
- Marine Steam Boilers
- Auxiliary Steam Boilers and associated steam plant
- Classification and types of Boilers
- Boiler Types
- Water Tube Boiler
- Fire Tube Boilers
- Cylindrical Scotch Boiler
- Aalborg AQ-series
- Cochran Spheroid
- Cochran Vertical Boiler
- Swirlyflo Spanner Boiler
- Sunrod Oil Fired Boiler
- Mitsubishi MC-Type
- Aalborg AQ12
- Package Boiler
- Coil type Package Boiler
- Drum Type Boiler
- D-Type Boiler
- Boiler mountings
- Safety Valves
- Safety Valve and Relief Valve - Definition and Terms
- Spring Loaded Relief Valve
- Boiler Safety Valve- Classifications and Definitions
- Low Lift Safety Valve
- Improved High Lift safety Valve
- Setting a safety valve
- Limitation of low lift safety valves
- High Capacity (Full Lift) safety valve
- Easing Gear
- Main Steam Stop Valve
- Feed Water Valve
- Water Level Gauge
- Feed Water System
- Boiler water testing and conditioning
- Boiler Water Treatment
- Combustion Process
- Air Register
- Types of Burner
- Automatic Combustion Control System
- Operation of Auxiliary Boiler
- Auxiliary Boiler Safety
- Forced Draft system
- Waste heat Boilers
- Composite Boilers
- Exhaust Gas Economiser
- Technical communications for design
- Concept of Technical Communication for engineers on board
- Application of Technical Literature to work
- Conclusion
- Operations of Main Diesel Engines
- Power in Diesel Engines a theoretical overview
- Compression Ratios of Diesel Engines
- Engine Dimensions
- Mean Piston Speed
- Engine Weight
- Selection of the working cycle
- Two stroke or Four stroke
- Diesel Engine Efficiency and Power Ratings
- Compatibility of Engine Output when coupled with Propeller
- Engine Characteristics and the Load Diagram
- Optimizing the Operating Point
- Engine Testing
- Performance-characteristics and criteria
- Trials of Diesel Propelling Machinery
- Other Tests
- Output measurement
- Presentation of Test result
- Monitoring and Evaluation of Engine Performance
- Assessment of Engine Power
- Power and Efficiency Calculations
- Understanding Combustion Process using Draw Card
- Performance Assessment by Indicator Cards
- Indicator diagrams
- How to Measure Indicated Power with Indicator Diagram
- Interpretation of Data from Monitoring Equipment
- Main propulsion performance and data
- Determination of Shaft Power
- Main propulsion shaft torque and speed measurement
- Shaft power meter MetaPower System
- Recognition of Irregularity in Performance of the Plant
- Study of Failures in the Combustion Process
- Early Ignition
- Late Ignition
- Compression, Combustion and the Expansion lines all too low
- After burning Post-combustion
- Failures Arising from the Indicator Mechanism
- Indicator drive Piston Sticking
- Planning and Scheduling of Engine Operations
- Slow Speed Steaming
- Running adjustments to maintain the performance of the Diesel engine as per the ship-operator’s preferences
- Safe operation and surveillance of propulsion plant and systems
- Safety and Protection System
- Automatic Control of Main Engines
- Control and alarm systems, associated with the automatic operation of a Diesel plant
- Alarm and Safety Systems
- Alarm Sequence
- Alarm System Layout and Testing
- UMS Operations
- Safety of Engine, equipment and systems
- Hazards to Safety during Operation
- Engine components-Loads, Stresses, Force, Moments and Vibrations
- Static and Dynamic Loads and Stresses
- Stresses on Engines
- Forces, couples and moments
- Out of balance gas and inertia forces
- Effects of Poor Maintenance and Stresses on Engine Structure
- Balancing of Engines
- Dynamic balancing
- Balancing of primary reciprocating force and why it is not completely successful
- Additions that may be fitted to overcome primary imbalance
- Additions that may be fitted to overcome secondary imbalance
- Vibration characteristic of Two-Stroke Diesel Engines
- Low-speed Main Diesel Engine
- Primary and Secondary Forces and Couples
- Guide Force Moments
- Axial Vibration
- Shafting lateral vibrations
- Torsional Vibration
- Torsional Vibration and Critical Speeds Explained
- Application of Elastic Theory for Torsional Vibration
- Study of onboard Excitation leading to Torsional Vibration
- Misalignment
- Misfiring operation
- Response from shafting system
- Stress limits
- Serious criticals of misfiring units
- More on resonance
- Design phase precautions for propulsion shafting
- Flywheel and Damper
- Fluctuation of Speed and Energy
- Vibration Dampers
- Silicone Damper
- Calibration and wear
- Cylinder Liner
- Ship Vibrations
- Excitation and Damping
- Measuring Vibrations
- ISO specs
- Alignment and adjustments
- Crankshaft deflection overview
- Crankshaft alignment and adjustment
- Propulsion Shaft Alignment
- Four Methods of Alignment
- Modelling Methodology
- Method used in Shipyard during Construction
- More on Propulsion Shaft
- Diesel Engine Emergency Operation
- Cutting out Cylinder Units
- Cutting off Fuel Injection Pump UEC-L Main Engine
- Effects of Decoupling of Cylinders or Engine Units
- Various Methods of Cutting Out an engine unit
- Other ME Emergency Operations
- Bad weather Operation
- Local Engine Operation Telegraph Failure
- Blackout
- Water Leakage into the Cylinder
- Operation with Turbocharger Breakdowns
- Wartsila-Sulzer
- UEC- Mitsubishi
- Precautions for Slow Running
- Scavenge Fire
- Crankcase Explosion
- Multi-engine Propulsion Arrangement
- Components and Systems associated with Marine Diesel Engines
- Operation of Gearing and Clutches
- Use of Gears
- Gear Teeth Design
- Lubrication
- Parallel gear Applications
- Epicyclic Gearing
- Star Gear
- Planetary Gear
- Solar Gear
- Advantages of Using Multiple Planets
- Epicyclic Gear Arrangements
- clutches and Reversing Gears
- Engine lubrication
- Bearing Lubrication and Clearances
- Function of a Lubricant and Types of Wear
- Lubrication of Slow and Medium speed diesel Engine
- Some definitions and Corrosion of White metal Bearings
- Contamination of Lube oil in service
- Use of additives in Lube Oil
- Maintaining Additive reserve
- Lube Oil system and optimum purification
- Shipboard Lube Oil tests and analysis limits
- Lube Oil analysis and suitability for further use
- Spectrographic analysis to check wear and tear of engine
- Guidelines to Interpretation of System Oil Analysis Results
- Test Yourself
- Shipboard Treatments
- Microbial Infection in System Oil
- Lubrication (2)
- Centrifugal Purifiers
- Fuel Injection
- Fuel oil system, including shipboard preparation of fuel oil for proper combustion
- Combustion of fuel oil
- Improper Combustion
- Fuel Pump
- Fuel Metering Principle
- Checking the Timing
- Power developed by an Unit
- Variation in Exhaust gas Temperature and Power Balance
- VIT Pump
- VIT in Valve Controlled Pump
- VIT in smaller Engines
- Electronic VIT
- Regulation of Quantity
- Checking and Adjusting Fuel Pump Timing
- Adjustment in actual pump timing
- Procedures during changing over of Fuel Oil
- Constant and Variable Injection Timing
- Changes in fuel system for different fuels
- Main engine fuel injector
- Deterioration of Fuel Injectors
- Troubleshooting of Fuel Injectors
- Nozzle Burning
- Replacement, Overhaul and Testing
- Multi Injectors
- Sheathing Fuel Pipes
- Fuel Injector
- Atomization, penetration, turbulence
- Injection pressure and viscosities
- compare injuction system of slow,medium and High
- OHS (Occupational health and safety) issues for overhauling fuel Injectors
- Fuel Valve Cooling system
- Pollution prevention from DE
- Unifuel and Dual fuel systems
- Effective control of Valve timings in DF engines
- Dual fuel 2-Stroke Low Pressure Diesel Engines
- Dual Fuel 2-Stroke High Pressure Diesel Engines
- 4-Stroke Dual Fuel Diesel Electric (DFDE) Engines
- Dual Fuel Engine Cylinder Oil System
- Safety System
- Gas and Fire Detection Systems
- Safety Functions - Dual and Gas Fuel Engines
- Ventilation System
- Electrical Equipment in Hazardous Spaces
- Types of Protection
- Certified Safe Electrical Equipment
- Mass Flow Rate meter
- Governor
- Mechanical Governor
- Mechanical Hydraulic Governor
- UG Governor
- Electronic Governor
- Overview
- Electromagnetic Pick-Up
- Governor Controllers
- Gain
- PID Control
- Installation of the actuator rod
- Scavenging and Supercharging
- Scavenging types
- Need and methods of Scavenging
- Scavenge Fires and Drains System
- Charge air methods and systems
- Turboblower arrangements
- Impulse System
- Constant Pressure System
- Blades of the constant pressure and the pulse turbine
- Assessment of pressure charging methods
- Two stage systems
- Other types Balanced system-variation on pulse
- Size 16.0 KB
- Charge Air Cooler
- Turbochargers
- Working and Types of Turbocharger
- Turbocharger with Axial Flow Turbine
- Radial Flow Turbocharger
- Types of Turbocharging
- Turbocharging Arrangements
- Impulse( pulse,blowdown,constant volume)
- Constant pressure
- Blades of the constant pressure and the pulse turbine (2)
- Two stage systems (2)
- Types of Bearings
- Ball Bearings
- Roller Bearings
- Ball Thrust Bearing
- Roller thrust bearing
- Tapered Roller Bearings
- Turbo charger - Bearing and Lubrication
- Surging - Matching with Engine
- Turbocharger Surging
- Causes of Turbocharger Surging
- Matching of turbocharger to engine
- Surging
- Conditions leading to Surging
- Turbocharger-Waterwashing
- Turbocharger - New Developments
- Hybrid turbocharger
- Construction of hybrid turbocharger
- Turbochargers matching to the Engine
- Development in turbochargers
- Modern trends in Turbocharger design for Large slow speeds
- Turbocharger
- Turbocharger Maintenance
- Turbocharger-Types and Operations
- Turbo charger Manual
- Description
- Dismantling
- Installing
- Trouble shooting
- Overhaul, Maintenance and Inspection
- Exhaust gas Turbocharger
- Starting and Reversing of 2-stroke Engines
- Starting Air System
- Starting the Engine
- Rotation of Engine In The Opposite Direction
- Timing diagram of a 2 Stroke Engine
- Lost Motion
- Axial Shifting of CAMS
- Rollers Displacement
- Regulatory Body Requirements For a Reversible Engine
- Electronic Operation
- Logical Sequence
- Reversing the Ship
- Engine with Reduction Gear
- Ships Fitted with CPP
- 2 Stroke Engine Connected To a Fixed Pitch Propeller
- Reversing
- Main Engine Manoeuvring System
- Bridge Control for an unmanned ER
- Precautions for Starting and Stopping
- Changing Over Fuel
- Starting and Reversing
- Engine Cooling Methods and Systems
- C.W. System Design
- Open and Close CW Systems
- Typical Cooling Systems of Large Marine Diesel Engine
- Centralized Cooling System
- Advantages and Disadvantages of Centralized Cooling System
- Operating Conditions and Safety Devices in CW system
- Problems in CW space
- Thermal efficiency and loads on engine components
- Selection and comparison cooling media
- CW testing and evaluation
- Checking Cooling Water and the System
- Typical Tests for Engine Cooling Water Treated With Dieselguard From Unitor
- Sampling and testing of cooling water
- Test Equipment – Unitor Spectrapak 309
- Test Methods
- Test Results
- Corrective procedures for out-of-limit parameters
- Cleaning of Cooling Water System
- Descaling Diesel Engine Cooling Water Systems- Unitor
- Main Engine C.W Notes from a Japanese Engine Maker
- Degreasing Cleaning of Diesel Engine Cooling Water Systems-Unitor
- Sources and types of CW contamination and its effects
- Problems associated with Cooling System
- Various types of Corrosion and Corrosion Mechanisms
- Factors Affecting Corrosion Rates
- Selection of Material for CW system
- Countering CW contamination
- Water Treatment
- Corrosion Inhibition
- Mechanisms of Corrosion Inhibition
- Cooling of components (piston, exhaust valve, Cylinder,TC, Cyl Head)
- Engine Cooling Water System
- Cooling Of Cylinder Heads
- Older and smaller Engines
- New Generation Engines
- Turbocharger Watercooling
- Design Features and Operating Mechanisms of MDE
Design Features and Operating Mechanisms of MDE
Design of Marine Machinery
In the basic design of Marine Machinery for main propulsion, the following points to be considered.
What type of Main propulsion Engine do we need? That depends on a number of factors, Cost of the engine and its delivery schedule; to be able to match the ship construction work in progress; designed machinery space available on the ship; the overall plant efficiency; specific fuel oil consumption; compliance to current and near future environmental restrictions for emissions; operating costs including spares and their ready availability; and issues involving important components like Turbocharger, Governor, the auxiliary engines and so on.
In many cases, the shipowners experience with a type of engine also makes a big difference; if a shipowner has deep experience with a particular slow-speed engine, it is unlikely that he will go for another. The company tends to build upon the skills of its workers and would feel uncomfortable introducing a different engine, e.g., just to save 0.5% of fuel economy. That is the reason the engine makers always try to introduce a new version of an engine at a discounted pricing until, the engine type has proven its worth on board. It took no less than 5 years for the super-long-stroke engines to gain its acceptance.
So, if new Technology is to be used, question will be, are they proven? And, are the current Maine Engineers capable of managing these engines or, would they require extensive additional training? These are the dilemmas of a shipowner.
Based on these points and mainly on the propulsion characteristics, either a diesel engine, with the latest available proven technological improvements or a COGES system (as the one seem to be a current preference) -- Again, initial cost plays a major role, One needs to pay more for the latest technologies. An alternator coupled with a Turbocharger which uses exhaust gas as a normal turbocharger, but also takes care of the complete electrical load, when the main engine is running; this combination was costing less, when it was introduced in the market; for the same engine system: the cost is more than doubled after it has been a success in the first few ships.
Since it is very important that the Engine and the propeller are correctly matched, their selection often goes in tandem. We can decide on the diesel engine and the propeller type- fixed pitch or variable pitch based on the availability of space where the machinery layout plays an important part. But the more popular choice today, for the larger ships demanding higher power , is to go for long stroke slow speed engine. Even if the vessel is not placed on a liner run and must tramp as demanded by the market. The winner here is the lower fuel consumption and ability to manipulate speed within a reasonable range with optimum efficiency. Whereas, if a LNG carrier is built, on a contract covering the life cycle period of the engine; and, with assured loading and discharge ports on fixed voyages; that commercial assurance, will certainly play a major role in selection of the main propulsion machinery, where new innovation can be supported with lesser commercial risks.
Improvement in Design
Engine manufacturers have been busy with a number of design improvements over the last decade; some of those are contribution from,
- Sophisticated methods of numerical analysis permit accurate predictions of the thermodynamic performance of the engine, the scavenging process, stresses, strains and deformations under both mechanical and thermal loads, heat transfer and temperature distributions in engine components and the vibration modes of complex structures.
- Mechanical design concepts such as bore cooling of the combustion chamber components, thereby achieving improved mechanical and thermal loads capacity with good reliability.
- New measurement and monitoring techniques on running engines for stresses, flow patterns, temperatures, providing more in-depth analysis and thus better design optimization.
- Improved turbocharger performance, which led to higher working cycle efficiency and enabled a higher specific engine output.
- Wear and corrosion of key components are kept within limits in spite of higher combustion temperature and pressure such as in exhaust valves, cylinder liners by improved materials, and better understanding of tribological problems with improved lubrication
- Electronic Fuel Injection and removal of Camshaft
- Electronic Governor with finer degree of control and ability to maintain engine RPM
- Common rail fuel injection with removal of fuel pumps from individual units
- Hydraulically driven Exhaust valves that operates electronically from a central engine computer
- Multiple fuel injectors in units improving the combustion efficiency
- Turbocharger re-circulation with better efficiency and stability at lower load operations
- Improved surveillance and monitoring of all hotspots and efficiency points, and many more.....
Ships Engines and propulsions: 2 and 4 stroke
- For the progressively larger powers and approaching the mega-ships, the continuation of slow rotating large propellers and directly coupled long stroke diesel remains a majority choice.
- The stem apertures of vessels have been redesigned to accommodate larger diameter propellers. The Hydrodynamic improvements have also been possible by adding all sorts of propulsion aids. e.g. ducts, fins, vane wheels, bulbs, asymmetric stems, flow straightening nozzles, propeller boss cap fins. etc.The present state of engine development appears to favor the two-stroke cycle for the large, slow-running, direct coupled engines and the four-stroke cycle engine for medium speed and high speed engines used for generators and indirect propeller drives.
High bmep increases the stresses on nearly all the engine components, with a consequently greater rate of cylinder wear, whilst the alternative of higher speed, valve flutter may become a serious problem.
But the 2 stroke engines have many more advantages,
- Each out-stroke being a working stroke gives more even turning for the same number of cranks, consequently a lighter flywheel may be employed.
- The operation of reversing the direction of rotation is simplified since there are not so many cylinder head valves to contend with.
- Fewer moving parts and lower maintenance
- Lower specific fuel consumption
- No gear loss
- Simplicity in construction
- Longer life time, Higher reliability
- Low lube oil consumption
- Better ability to bum low quality fuel oil.
The 4-stroke engine have good volumetric efficiency, Good combustion characteristics, Positive exhaust scavenging and a less arduous lubrication requirements due to the presence of an idle stroke which allows spread of lubricating oil through bearings and around the liner. The thermal and mechanical efficiency are slightly better than those of two-stroke engine. In this type of engines only half the quantity of the heat generated in the cylinders has to be dealt with a given time, so that efficient lubrication of the piston and cooling of the cylinder is more easily accomplished.
The followings are also advantages of using four stroke engines:
- Lower initial cost for equivalent power
- Ease of installation
- Lower weight per power output
- Saving in weight and engine room length
- Increase cargo capacity
- Free choice of propeller speed through gearing
- Suitable for electrical power take
In conclusion it can be summarized, that from a purely efficiency and usefulness point, both 2 stroke and 4 stroke engines have made their presence felt within the maritime sector. In that larger vessels have been using slow speed 2 stroke, whereas the smaller vessels made use of the 4-stroke engines, which due to their higher speed could generate higher power and did not need a lot of space. Thus, the choice has been largely driven by commercial suitability.
The current trend toward newer plant designs with combined cycles and better Waste Heat Recovery and also with electric propulsion initiatives, the medium speed engines could become a strong contender. The push for burning better fuel and gas could also tip the balance toward more application of the 4-cycle and even higher theoretical efficiency in gas burning via Otto cycle is on vogue.
Wärtsilä and MAN- B&W are the foremost license providers across the globe; in 2015, they accounted for more than 95% of the global low speed engine market share and over 75% of medium speed engine market share. At present, Japan, China, and South Korea collectively account for over 80% of the regional marine diesel engine market size..Global marine diesel engine market size was valued at around USD 6 billion in 2015 and is anticipated to exceed USD 8 billion by 2023, with growth rate at over 4% from 2016 to 2023.
Industry Analysis
Marine Propulsion Engine Market size was over USD 9 billion in 2015, and is anticipated to grow at 4.3% CAGR from 2016 to 2024.
