Pentti Häkkinen ER auxiliaries 9.1 Wärtsilä New Professionals 3.-7.11.2008 Machinery Auxiliary Systems Contents and Targets Supplementary to Project Guide.

Pentti Häkkinen ER auxiliaries 9.1Wärtsilä New Professionals 3.-7.11.2008

Machinery Auxiliary Systems

Contents and Targets

Supplementary to Project Guide. Presentation focuses on system part in excess of engine system diagrams.

Target is presentation of real systems and their components in ships.

Many auxiliary systems are not dependent on engine power or transmission mode (electric - mechanical)

Most are more dependent on number of main engines and number of main engine compartments

Redundant engine rooms should be based on reliability and maintainability analysis

Simple is beautiful! This is valid for all systems.


Fuel Oil Systems

HFO treatment plant in ship now receives ample attention. It hardly depends on fuel quality.

Fuel fed to engine must be

• homogenous

• clean of particles

• in correct viscosity

• in correct pressure

• ample circulation flow

This requires proper systems for

• bunkering,

• storage,

• transfer,

• purifying,

• feeding

Every stage consists of potential hazards, both in system design and ship operation


Fuel Oil Bunkering

Bunkering place depends on price and quality. Extra fuel is carried onboard for one or two roundtrips.

Bunkering stations on both sides. Capacity to receive 100 … 1000 m3/h. Most ships have own volume counters.

Standardised flanges for HFO and MDO to prevent errors.

Gravity filling when delivered to shipside.

Station is arranged so, that fuel entering in overflow pipe is immediately detected.

Fuel related problems are well-known. Most owners utilise analysing services: Sample dripped into sealed bottles. New fuel is kept separate to avoid compatibility problems.


Fuel Oil Bunkering

Most ships have own volume counters.


Fuel Oil Bunkering and Storage

HFO overflow tank

Bunkering station midship, open deck (sometimes engine room fore corner)

HFO storage tanks P & SB

HFO suction line

HFO drop fill line in double bottom pipe tunnel

HFO pump suction line

HFO transfer pumps

DO transfer pump(often purifier pump)

HFO settling t.

day tanks

settling t.

DO transfer pump

DO day tank

DO storag t.

DO Emerggener. tank

transfer pump dimensioned for max. 6 h / day


Fuel Oil Storage and Transfer

HFO is stored in deep and DB tanks. Fore and aft tanks help optimal trim. Not against shell!

HFO tank & transfer pipe heating is major energy consumer. Many new cargo ships have deep tank groups, not extending to sides.

Dimensioning: largest tank kept at 40oC while second largest is heated up.

HFO transfer pump feeds fuel to settling tanks. Two tanks for safety and flexibility.

Storage tank equipment: sounding: remote and local, air pipes, overflow pipes, heating coils in bottom & around suction bell,

Settling tank allows water and impurities sedimentation on bottom. Equipment: heating coils, insulation, water drain, suction above bottom, baffle plates. High tank with inclined bottom. Kept at constant temperature 60oC.


Fuel Oil Transfer and Purifying

Overflow line from HFO day tank to settling tank

Water drain in all fuel tanks

HFO day tank

Purifier feed pumps

Cooler Preheaters

To sludge tank From DO storage DO feed pump

From HFO transfer pumps

Separate day tanks for HFO and MDO


Fuel Oil Transfer and Purifying


Fuel Oil Feeder Systems

HFO day tank DO day tank

Cooling coil Pressure setting

De-aeration (mixing) tankFlow

meter

Viscosimeter

Pressure setting after ME

Self cleaning filter, manual bypass filter

Clean leak Dirty leak

Never more than 3 engines connected to one system


Fuel Oil Feeder Systems

Never more than 3 engines connected to one system


Positions of Fuel Oil Treatment Units

Diesel Oil HFO Storage tank Storage tank

Fuel purifiers HFO Settling tk Service tk HFO Storage tk

Overflow tk (Port side)

Preferably no HFO tanks against sea


Positions of Fuel Oil Treatment Units

Fuel Oil HFO Storage transfer pumps tanks

HFO Storage tanks also in fore ship


Fuel Oil Feeding Systems

Practical engine room designer topics

Only two engines fitted into one system

Location of booster module:

• ‘fuel corner’ is recommended, together with fuel purifiers

• rather high distance from engines accepted

• protected piping route! Not near walkways, delicate components nor areas where heavy loads are moved.

• module maintenance aspects. Insulated pipe is no footstep!

• plan a safe escape route in case of fire



Damping of pressure pulses• Injection pump causes short duration pulses

• Level 15 bar in common, even 80 bar measured

• Mild failures: pressure sensors, ..

• Serious failures: pipe ruptures

• Level is difficult to predict, level depends on many parameters

• IMO will set limit to 16 bar or double wall pipes required

• Many types of dampers are used



Common problems:•frequent filter clogging: incompatible fuel, small filters, purifier problems

•element cavitation caused by water or gas in fuel

•screw pump seizure as result of excessive recirculation

Fire hazard • MDO spray ignites immediately when hit on a hot (>150C) surface.

• HFO ignition almost equivalent

• Protective shielding around flange connections with leak monitoring

• Location of fuel lines, delicate and hot equipment

• Highest heat is directed above the flames


Fuel Oil Equipment on Engine

Injection pumps and pipes are generally well encapsulated

Pressure control valve fitted on each engine

Supply and return pipes must tolerate constant movement of resiliently mounted engine

Leakage oil pipes (clean and dirty) monitored by level switch, trace heating needed

Engine driven fuel circulation pumps common, especially in auxiliary engines

Emergency operation secured with gravity MDO tank or pneumatic pump


Lubrication Oil Systems

Separate system for each engine. Right design of circulation tank important.

Note main pump height and its suction capacity. Cavitation is common!

Both automatic filter and safety filters are installed

Continuously operating oil clarifier in by-pass line

Stop valves in sump drain pipes are required if no cofferdam is built below circulation oil tank. They prevent water entering in engine and machinery space.

Cooler and thermostate valve are often built on the engine

Purifier suction in the lowest point

Vent pipe led to engine casing

Oil level



Engine driven pumps are preferred if several main engines. Electrically driven priming pump, its capacity depends on duty.

Two full size electrically driven pumps are standard for single engine ships

Emergency lubrication arrangement needed in special cases (when no disconnection clutch). Gravity tank or pneumatically driven pump

Stop valves in sump drain pipes are required if no cofferdam is built below circulation oil tank

Flexible pipe joints in case of resiliently mounted engine




CP Propeller Lubrication Oil Systems

CP-propeller oil system is integrated for pitch control, cooling and lubrication of mechanisms.

Separate from any other oil system. Typically two electrically driven pumps, filters and coolers assembled on top of storage tank.

Emergency lubrication arrangement needed in special cases.

Monitoring of water content and metal debris in oil is important. Contaminated oil lot is replaced. Can also be purified with centrifuge unit.


Positions of Fuel and Lubrication Oil Equipment

LO circulation tank (more LO tanks in double bottom)

LO pumps LO coolers and filters

FO booster module (to CL of HFO service tank)

LO purifiers


Steam and Fresh Water Systems – MS Seahorse

30 35 40 45 50 55 60 65 70 75 50 55 60 65 70 75

Fresh w generatorCondenserSanitary water treatment

Fresh water tanks P & S 2 x 100 m3


Overhaul and Material Transport – MS Seahorse

Traverse crane above main engine

Engine Engineer store workshop

(Port) Heavy main engine spare parts secured

30 35 40 45 50 55 60 65 70 75-5 0 5 10 15 20 25

Bunkering stations P&S

Lifting rail above in the shaft tunnel


(Port) Heavy engine spare parts secured

Overhaul and Material Transport – MS Seahorse

Engine Engineer store workshop

30 35 40 45 50 55 60 65 70 75 50 55 60 65 70 75

Lifting rails above diesel gensets, in workshop and store

Service hatches to weather deck at service crane reach


Oil Treatment and Storages – MS Seahorse

Bunkering station P&S on main deck 19500

HFO settling tank

HFO transfer pumps (on the tanktop)

Boiler feed water 44 m3

Leak oil tank 15 m3

Oil circulation tank 50 m3 CW drain

tank 18 m3 AE LO tank 10 m3

Distribution box 25 m3

Low sea chest

HFO overflow 35 m3

Leak Oil 8 m3

HFO day tankHFO storage

150 m3

DOUBLE BOTTOM TANKS in 50 % scale

HFO DB stor.


Oil Treatment and Storages – MS Seahorse

30 35 40 45 50 55 60 65 70 75 50 55 60 65 70 75

HFO settling and day tanks

HFO purifiers & booster unit

AE booster unit

MDO storage tanks

LO tanks

LO purifiers

Cylinder Oil tank 50 m3Access to steering gear

AE LO units


Lube Oil and Cooling Water Systems – MS Seahorse

LO circulation pumps

Central coolers

LO transfer pump

LO filter

Main SW pumps

SW filters

LO automatic filter

Fire pump

Aux. SW pumps

Fire pump

Sea chests

Pentti Häkkinen ER auxiliaries 9.1 Wärtsilä New Professionals 3.-7.11.2008 Machinery Auxiliary Systems Contents and Targets Supplementary to Project Guide.

Documents

transfer hfo

new fuel

hfo transfer pump feeds

tank transfer pump

fuel oil storage

hfo tank transfer pipe

fuel quality

wrtsil new professionals