Bilge System• Basic requirement is to provide effective drainage to all dry spaces and at the same time prevent water from entering the spaces through this system.• Discharge of oily water from machinery spaces is to comply with MARPOL Annex 1• Oily water is treated in an oily-water separator before being allowed to be discharged.• Discharge water must be monitored with purity not to exceed ppm set by MARPOL.
Bilge SystemBilge main diameter, dm d m = 1.68 × L × ( B + D ) + 25 (mm) L = length of ship B = Breadth D = DepthBranch bilge main diameter, db d b = 2.15 × l × ( B + D ) + 25 (mm) l = length of compartment
Bilge SystemBilge pump capacity, Q 2 dm Q = 5.75 × 3 (m3/h) 10• Two bilge pumps are required• Suctions are arranged such that water can be pumped out when ship is inclined 5°• Arrangement must be such that water cannot pass from sea or ballast system into dry spaces through the bilge system
Ballast System• For safe operation, at least two ballast pumps are to be connected to ballast tanks.• Stripping eductor can also be used for emptying the bilges in cargo holds with 2 non-return valves between hold and system• Ship side valve material must not of grey cast iron and to direct mechanical manual operate
Air and Sounding SystemsPurposes• to secure ventilation of tanks, cofferdam and tunnels to prevent over-pressurizing and vacuum (air pipes)• to ascertain the level of liquid in tanks, cofferdam and tunnels (Sounding pipes)• Vent pipes need to prevent flooding of spaces through their upper ends• Vent pipes need to safely prevent flammable liquids or vapours due to their fire hazards
Air and Sounding SystemsMachinery Spaces• Heavy fuel oil overflow tank has short self-closing type sounding pipe• HFO overflow tank air pipe is led to open deck as required.• Lubricating oil sump tank air pipe may end inside machinery space but away from ignition sources
Air and Sounding SystemsMachinery Spaces• Air or overflow pipes internal are are normally required to be 1.25 times the area of respective filling pipes for a tank.• Velocity in the air pipe is not to exceed 4 m/s when using one pump for one tank.
Fire-Fighting SystemsThree groups:• Fire Main – Seawater as fire extinguishing medium – At least two fire pumps and are located in two different compartments – An international shore connection is provided at port and starboard for external water supply – System is tested with at least streams of water directed from one fire pump. – Pressure relief valve is fitted to mains to protect sudden over-pressure.
Fire-Fighting SystemsThree groups:• Carbon Dioxide system – Dry fire protection – Used in compartments that have potential for fire: engine room, emergency generator room, paint locker and galley hood – System is equipped with audio and visual alarm to alert personnel to evacuate – Prior to CO2 release, ventilation fans and fire damper to be shut.
Fire-Fighting SystemsThree groups:• Sprinkle system – Wet fire protection mainly for accommodation area – System is filled with fresh water and pressurized by compressed air – Subsequently, water is supplied from fire main – Sprinkle and fire main systems are separated by an alarm check valve. – When the pressure in the sprinkle drops below the fire main fire pressure, the fire main pressure will overcome the internal pressure of the valve lift and automatically push open to accommodate the fire main.
Fuel Oil SystemsMain concerns• Fire hazards – Flash point – Insulation – Remote control of fuel oil valves – Stopping of pumps – Collection of drains from leaks• Materials – Fuel oil pipes and their valves and fittings is required to be of steel or other fire-resistance materials
FO Storage and Transfer FO Storage and Transfer
FO Storage and TransferImportant concerns• Overflow pipes• Quick-closing valves• Drain to waste oil tanks (spill trays)• Level gauge with heat-resistant glass for sounding• Remote control of fuel oil valves• Insulation of hot surfaces where fuel oil leaks (possibly in a spray form) is possible
Lubricating Oil Storage and TransferMain components• Filling from deck to tanks• Main LO storage tank to deliver to ME sump tank• Quick-closing valves operable from outside ER where valves are below top of tanks (not applicable for small tanks below 0.5 m3)• Air pipes may terminate inside ER provided their openings do not constitute a fire hazard• Duplex filters (or self-cleaning) are used without interrupting operations
Seawater Cooling SystemArrangement• Conventional and Central cooling• High and low sea chests• Suctions are arranged from two sea inlets preferably on the opposite sides of the ships• Filters can be cleaned without interrupting the water supply in the system.• Temperature controlled three-way valves to re- circulate water when the water is cold
Freshwater Cooling SystemFreshwater Cooling System
Freshwater Cooling SystemArrangement• Freshwater from engine is delivered to freshwater generator (evaporator)• Pressure in the system is regulated by he expansion tank• Temperature-controlled three-way valves to allow re-circulation• High-temperature circuit (jacket cooler), low- temperature circuit (lubricating oil)
Compressed Air System• Normally three systems – Starting air – Service air – Control air• Require two main compressors to charge two air receivers from atmospheric within one hour• Capacity of receivers sufficient to produce: – 12 starts for reversible engines – 6 starts for non-reversible engines – 3 starts for auxiliary engines
Compressed Air System• No connections to other machinery between air compressors and main air receivers• Emergency air compressor can be diesel driven or power supplied from emergency generator• Pressure reduction stations and filters are required to be duplicates• Safety relief valves are fitted at receivers and set at 10% above operating pressure• Compressed air line is classes as Class II due to high pressure.
Domestic Water System• Freshwater is made by Freshwater generator (evaporator)• Delivery of water to accommodation from hydrophore units is by compressed air• Domestic water is sterilized before consumption• Domestic water is heated and then circulated (by hot-water circulating pumps)• Domestic water is also used by HFO, DO and LO separators
Steam System• Normally divided into: – Feed water systems – Steam supply • For heating tanks • For heating pipelines • To heat exchangers – Condensate• Heat of exhaust gas is recovered in economizer to generate steam• Diesel propulsion system is normally fitted with an auxiliary boiler
Steam System• Steam with pressure above 7 bar or temperature above 170°C are considered Class II piping.• Steam with pressure above 16 bar or temperature above 300°C is of Class I piping.• With respect to materials for valves and fittings in Class II piping system, grey cast iron may not be used up to ND 200, pressure up to 13 bar and temperature up to 250°C