Marine Steam Boilers by Lars Josefsson

Marine steam boilers


Important marine steam boiler information for technicians and engineers using marine boilers, water-tube boilers or fire-tube boilers, with heavy fuel oil burners or coal fired furnaces.
Know-how is the keystone of all boiler operations; pioneer Scotch marine boilers as well as modern water-tube boilers and diesel engines exhaust gas boilers.

Steam boilers

Boiler Questions
Marine steam boilers alarm and trip functions The most important alarm and trip functions on marine steam boilers.
Marine boiler control automatic An easy way to find out if your marine steam boiler control system lights up the first burner safely.
Marine boiler Control The very best way to get redundancy in a marine steam boiler plant would be to have two completely independent one boiler control systems.
Marine boiler Safety marine steam boiler plants require adequate control systems to raise steam, maintain design conditions for steady steaming, secure the boiler units and detect promptly malfunctions and failures.
Fail-safe, Marine boiler control Fail-safe; any predictable failure must result in a safe situation.
Marine steam boilers Steam and Water Steam flow diagram for an exhaust gas boiler and two oil-fired auxiliary Marine marine steam boilers.
Marine steam boilers Heavy Fuel Oil Fuel Oil flow diagram for two oil-fired auxiliary marine marine steam boilers
Marine steam boilers water level control Sophisticated methods are required for a steam-boiler with high steam production and relatively small water volume.
Two marine boiler operations Keeping a slave steam-boiler pressurized in a two boiler system.
Marine steam boilers HFO firing How to burn marine bunker oil.
Marine steam boilers Smoke Density Meter A plant that never shows traces of smoke at the funnel is not burning the fuel efficiently.
Steam boilers Waste oil firing in marine steam boilers Is the sludge a waste oil just to get rid of or is it a valuable fuel?
Heat transfer media: steam, oil and water A comparison between the heat transfer media

Marine steam boiler Accessories

Marine boiler's Steam sootblowing A steam soot blower consists of a number of nozzles on a pipe that rotate and sometimes moves axially between the banks of tubes.
Marine boiler's Water soot washing A water washing devise is normally a number of water nozzles placed over the tubes and the water washes the tubs and the sooty water is then collected in a pit below.
Marine boiler's Infrasonic soot cleaning Infrasonic sound from a special loudspeaker make the soot vibrates off the tubes. Very effective boiler accessories.
Marine boiler's Steal balls soot cleaning Small steel balls falling from the top of the boiler, bouncing from one tube to the next one.
Steam boiler's Rapping soot cleaning By rapping the fouled convection heating surfaces the tubes are caused to vibrate so that the deposited combustion residues fall off. It is designed to be used during boiler operation.
Marine boiler's Combustion air preheater While the utilization of the waste heat in the chimney gases for preheating the combustion air supplied to the boiler furnace, by means of air heaters, has long had a wide use, as, for example, in the Howden air heater.
Marine boiler's Superheaters Superheaters are essentially a bank of tubes, in the exhaust gas duct after the boiler, used to heat the steam above the saturation temperature.

Marine Boiler Constructions

A Scotch marine steam boiler consists of a steam drum and one to four fire-tubes in which furnaces heats the steam-boiler. A water-tube Marine boiler is a steam generator consisting of a steam drum and water-drums and tubes which are exposed to the heat of a furnace and arranged so as to promote rapid water circulation in the steam-boiler. At high pressure, providing a more positive means of maintaining the circulation becomes desirable and advantageous. The Controlled Circulation Boiler design is an ideal arrangement for boilers in the high pressure range. With its features of positive circulation, compactness, light weight, suitability for high pressure and temperature, and adaptability to limited space conditions, Boilers with Controlled Circulation can offer important advantages for advanced steam power station design.
Babcock Wilcox marine steam boilers In a Babcock & Wilcox water-tube steam-boiler are the water-tubes lying, but slightly inclining towards the boiler front
Belleville marine steam boilers The marine steam boiler feed water was fed into the to the feed water collector, at the lower end of the tubes, by means of an automatic feed water controller
Carlsund marine marine steam boilers Still very low steam pressure but you can see some of the Scotch marine steam boiler's ideas already used
Combustion Engineering V2M8 marine steam boilers V2M8 marine steam boiler whose major design features are the gastight waterwall furnace and the vertical in-line inverted U-loop superheater
Combustion Engineering V2M9 marine steam boilers The most outstanding feature of the V2M9 marine steam boiler is the combustion
Cochran marine steam boiler The Cochran marine steam boiler has a dome-shaped furnace top that forms the bottom of the boiler itself
Composite boilers Composite marine steam boilers are combination of oil-fired boilers and exhaust gas economizers
Eckrohr marine steam boiler Eckrohr marine steam boiler, Corner Tube marine steam boiler, is a marine steam boiler for all kinds of fuel. Originally it got its name because it has downcomers in the four corners
Exhaust Gas marine steam boilers Exhaust Gas marine steam boilers also known as Exhaust Gas Economizers, with extended heating surface, used for waste heat recovery in motor ships
Fraser marine steam boiler These marine steam boilers didn't have tubes, but plate-ducts for the exhaust gases to pass through the water space
Gunboat marine steam boilers The gunboat marine steam boilers were, as the name indicates, used in small navy ships such as gunboats, escort vessels and corvettes where the width and the height were limited
Howden-Johnson, a hybrid Scotch marine steam boiler The Howden-Johnson marine steam boiler tried to improve the poor water circulation in the common Scotch fire-tube boilers by adding water-tubes in a dry-back combustion chamber
LaMont, Forced circulation marine steam boiler The LaMont marine steam boiler is a once-through or semi-flash boiler in which the boiler water is circulated by means of a pump through long closely spaced tubes of small diameter
Normand marine steam boilers The main difference between the Normand marine steam boiler and the Yarrowboiler is the external downcomers.
Nuclear marine steam boiler Nowadays marine nuclear marine steam boilers are used in large navy ships and icebreakers serving in Arctic waters
Prud'Hon Capus, a hybrid Scotch marine steam boiler It was claimed that this modification made the Prud'Hon Capus boiler 10 per cent more efficient than conventional Scotch fire-tube marine steam boilers
Schulz marine steam boilers Schulz marine steam boiler has three water drums at the bottom; connected to the steam drum by means of bended tubes that discharge below the water level in the steam drum
Scotch marine steam boilers A Scotch marine steam boiler consists of a steam drum and one to four fire-tubes in which furnaces heats the boiler
Marine steam generators SKI, once through boilers Standardkessel Italiana has produced the SKI steam-generator.
Marine Steam generators TT, once through boilers The steam generator is a mono tube flash boiler. "Once through boiler" means that the feed water enters into one end of a heated tube and steam exits from the other end
Stirling marine steam boiler The Stirling marine steam boiler was originally built by The Stirling Consolidated Boiler Company in Baberton, Ohio, U.S.A., until 1906, when Babcock and Wilcox bought the design from them
Sunrod marine steam boilers In a Sunrod marine steam boiler a waterwall makes a gas-tight furnace from which the flue gases pass through the Sunrod pin tube elements to the smoke-box on the top of the boiler. The Sunrod boilers are nowadays manufactured by Aalborg Boilers.
Thornycroft marine steam boiler These marine steam boilers have an upward narrowing shape and call for, especially if they are placed side by side, a larger space than other square-shaped boilers
water-tube marine steam boiler A water-tube boiler consists of a large number of closely spaced water-tubes connected to one or more drums, which act as water pockets and steam separators, giving rapid water circulation and quick steaming
Yarrow marine steam boilers A Yarrow marine steam boiler consist of an upper steam drum connected by banks of inclined water-tubes to two lower water drums

Marine boiler service

Boiler accessories Provider of boiler room products and systems for the safe and economical operation of marine boilers."
Boilermakers Marine boilermakers as well as marine boiler worldwide repair-services for firetube and watertube boilers.
Boiler Control system Control systems for marine steam boilers, components such as control-valve and transmitters as well as complet boiler control and safety systems.
Boiler feedwater treatment Provider of feed water treatment equipment and necessary chemicals for proper boiler water handling
Burner Manufacturers Heavy Fuel oil burners for marine boilers. Pressure atomizing, steam atomizing and rotary cup burners
Marine magazines Merchant Shipping Magazines for seafarers and technicians
Classification societies

Marine steam boilers level sensors

Advanced methods to measure and control the water level in a marine boiler. Using one level method for controlling the marine boiler level and another for the level alarms and boiler trip-functions would be quite wise. Differential pressure transmitter is a common method for measuring the level in a marine boiler.
Marine boiler level differential pressure This boiler level measuring method uses a differential pressure measuring system with "wet leg", that is, the impulse pipes to the positive measuring point below the lowest water level and the impulse pipe to the negative measuring point above the highest water level, are both filled with water
Marine boiler level capacitance electrode An insulated electrode is placed in the boiler and the length should be sufficient to reach the water at all acceptable levels. The insulated electrode and the boiler work as a capacitor with the water and the steam as a variable dielectric medium
Marine boiler level conductivity electrode It's normally one boiler level electrode for emergency low water level alarm, or two electrodes if also high level alarm is required. This water level sensing method is also common on small boilers for start and stop of the feed water pumps
Marine boiler level float Boiler level float switches have been used for decades as level switches in boilers, but nowadays electrodes have replaced them
Marine boiler level displacer A boiler level displacer (a float heavier than the water) is suspended to a spring balance by means of a stainless steel cable or a rod

Marine steam boilers feed water treatment

The marine steam boiler feadwater system is very important for the steam production. The steam-boiler feed water quality is essential to protect the marine steam boiler from harm.
Oil in marine steam boilers feed water Beware of oil in the boilers feed water system
Boiler blowdown Optimizing Bottom-Blowdown from marine steam boilers
Marine steam boilers feed water heating The first and most important use for the exhaust steam is to heat the feedwater, since all of the heat of the exhaust steam so utilized is returned undiminished to the boilers
Marine steam boilers feed water treatment The presence of impurities in boiler feed water is a constant source of concern to the operating personnel, because it affects not only the efficiency of the boiler, but also its safety
Marine steam boiler scale The mineral and organic substances present in natural water supplies vary greatly in their relative proportions, but are principally comprised under the carbonates, sulphates and chlorides of lime, magnesia and sodium, iron and aluminum salts, silicates, mineral and organic acids, and the gases oxygen and carbon dioxide.
Corrosion within marine steam boilers The boiler corrosion process is essentially an oxidationl reduction reaction. It may occur in various forms including the special form known as caustic cracking. The most usual forms, however, are pittings and general wastage
Marine steam boiler water treatment The importance of the correct method of applying treatment chemicals cannot be over-stressed. Additions of hydrazine to the feed water must be continuous and sufficient quantity to remove the last traces of oxygen from the feed water and to leave a small excess
Marine steam boiler water test Because of the inherent difficulties involved in any attempt at automatic control of feed water treatment, it is necessary that the exact condition of the boiler water be known from day to day, in order that necessary treatment can be applied for the correction of any unsatisfactory conditions which may exist
Boiling out a marine steam boiler Boiling out before the boiler is placed in service to remove any foreign products
Care of idle marine steam boilers Several methods are available for storing idle boilers to prevent corrosion. The choice will depend on whether or not long term storage is required or if, for short time storage, the boiler need to be available at short notice

Atomizers for marine boiler HFO burners

Marine steam boilers today are mainly HFO fired. Different methods are used to atomize the fuel before the combustion in the steam bolers furnaces.
Fuel pressure jet atomizer The pressure jet atomizer utilizes the supply pressure energy to atomize the fuel into a spray of finely dispersed droplets
Intenal mix steam atomizer The burner lance consists of two concentric tubes, a one-piece nozzle and a sealing nut. The media supplies are arranged so that the steam is supplied down the centre tube and the fuel oil through the outer tube
External mix steam atomizer The steam-assisted pressure jet burners atomizer is designed to make full use of pressure jet atomization at high outputs and full use of blast atomization at low outputs
Rotary cup atomizer The fuel oil flows at low pressure into the conical spinning cup where it distributes uniformly on the inner surface and throws off the cup rim as a very fine oil film
Low pressure air atomizer The principle is similar to that of the rotary-cup-atomizer, but the fuel is forced to rotate in a fixed cup by means of a forcefully rotating primary airflow
Medium pressure air atomizer Boiler plant usually employs the medium pressure air atomizing burner that is capable of extremely fine atomization and low pollution
Blue flame burner atomizer In the blue flame burner some of the hot gases from the flame are recirculated back to the inlet where they mix with and heat the combustion air

These Windows programs may be used free of charge

FUEL OIL Calculation Program
UNITS Conversion Program

Steamships propulsion

Steamships propulsion introduction
Compound steam engines
Triple steam engines
Quadruple steam engines

Steam-engine valve-gear

Caprotti valve-gear for marine steam-engines
Carlsund thread for marine steam-engines
Flodman's valve-gear for marine steam-engines
Gooch valve-gear for marine steam-engines
Hackworth valve-gear for marine steam-engines
Klug valve-gear for marine steam-engines
Stephenson link motion for marine steam-engines
Stompf unidirectional

Important links

Glossary of boiler terms
Karlshamn my home-town, a small town in the southern part of Sweden.
Include steamesteem index files Still Sailing Steamships
Steambships owners

My name is Lars Josefsson. I am from Sweden and I have worked with marine steam boilers and heavy fuel oil burners almost all my life. During the years I have designed automatic control systems for more than one hundred boilers for ships that are sailing on the seven seas in tankers, cruise liner, general cargo ships, etc
By Lars Josefsson

Mailing address:
Mr. Lars Josefsson
Prästslättsvägen 18,
374 40 Karlshamn,