Tuesday, August 6, 2013
INTRODUCTION
1) KNOW THE NEED FOR STEAM ON A MOTOR VESSEL.
2) KNOW THE PRINCIPLES INVOLVED IN HEAT TRANSFER AND IN GENERATING STEAM IN A BOILER.
3) KNOW THE VARIOUS WAYS THE BOILERS CAN BE CLASSIFIED.
4) KNOW THE BASIC CONSTRUCTIONAL FEATURES OF SOME
OF THE POPULAR BOILERS USED.
OF THE POPULAR BOILERS USED.
USE OF STEAM
1) HEATING DUTIES: ME FUEL OIL HEATER, PURIFIER HEATER, OIL
TANK HEATING, CARGO HEATING, AIR CONDITIONING & HEATING PLANT, CALORIFIER,
GALLEY SUPPLY, SEA-CHESTS, TRACER LINES FOR PIPELINE HEATING ETC.
2) RUN TURBINE GENERATORS
3) RUN CARGO PUMP TURBINES IN TANKERS
4) DRIVE STEAM DRIVEN DECK MACHINERY LIKE WINCHES ETC. OPERATE
BILGE, STRIPPING AND OTHER STEAM DRIVEN PUMPS DRIVE BOILER FEED PUMP TURBINES
5) EVAPORATOR/FRESH WATER GENERATOR HEATING MEDIA
6) TANK WASHING IN TANKER SHIPS AND GENERAL CLEANING FOR BOILER SOOT BLOWING AND FOR THE STEAM ATOMISED BURNERS
7) FIRE FIGHTING AS USED IN STEAM SMOTHERING SYSTEM
8) MAIN ENGINE JACKET F.W. PREHEATER AND LUB OIL SUMP AND DRAIN TANKS
9) USE IN THE WASTE OIL, INCINERATOR, SLOP TANKS
10) USE AS A STEAM EJECTOR MEDIA FOR EJECTOR PUMPS AND VACUUM DEVICES WATER GENERATOR HEATING MEDIA
TYPES OF BOILERS
1) MAIN BOILER- PROPULSION OF THE VESSEL
2) AUXILIARY BOILER-HEATING OF HEAVY FUEL OIL USING A STEAM
HEATER, NECESSARY FOR PROPULSION WOULD QUALIFY THE SUPPLYING BOILER TO BE
REFERRED TO AS AN
AUXILIARY BOILER.
AUXILIARY BOILER.
3) TANK BOILER- A BOILER WITH LARGE WATER CARRYING CAPACITY
WHERE THE SHELL IS BEING USED AS THE PRESSURE VESSEL. MOST LOW PRESSURE
AUXILIARY BOILERS WILL COME INTO THIS CATEGORY.
4) EXHAUST GAS BOILER- BOILER OPERATED BY HOT GAS FROM ENGINE
OR OTHER EXHAUST GAS SOURCES.
5) DRUM TYPE BOILER-WATER TUBE BOILERS EMPLOYING STEAM AND
WATER DRUMS. THEY ARE ALSO KNOWN AS BENT TUBE TYPE BOILERS.
6) PACKAGE BOILER -FULLY AUTOMATIC, LOW CAPACITY BOILERS
PACKAGED INSIDE A BOX TYPE CASING, CAPABLE OF QUICK STEAM PRODUCTION AND
FLEXIBLE IN BEING POSITIONED ANYWHERE; COULD BE COIL TYPE OR FIRE TUBE TYPE.
SMOKE TUBE & WATER TUBE BOILERS
PRINCIPLE OF HEAT TRANSFER IN BOILERS
LIMITING THE STRESS
MAX WORKING PRESS. = MAX STRESS X 2 X WALL THICKNESS/DIAMETER
THEREFORE TANK TYPE BOILER MAX PRESS LIMITED TO 17.5 BAR
COMPENSATING PADS
POSITION OF MANHOLES
COMPENSATING RING
SUPPORTING FLAT SURFACE
SUNROD CHS
MIURA Z - BOILER
WATER TUBE BOILER
BLUE: THE DOWNCOMERS LEAD THE WATER FROM THE STEAM DRUM TO
THE WATER DRUM AND THE WATERWALLS
HEADERS.
HEADERS.
RED AND BLUE: THE EVAPORATION TUBES AND THE WATER WALLS LEAD
THE WATER AND STEAM EMULSION BACK TO
THE STEAM DRUM.
THE STEAM DRUM.
RED: THE STEAM PASSES THROUGH THE SUPERHEATER BEFORE IT
LEAVES THE BOILER FOR THE CONSUMERS.
KEEP SUPERHEATER VENT OPEN AND MAINTAIN FLOW TO PREVENT
OVERHEATING.
