Boiler Glossary
Air fuel ratio – the ratio of the mass of air to the mass of fuel
AOTC – is the Associated Office of the Technical Committee. Now is SAFed.
Ash free basis – the percentage of the ash has been subtracted and the other
constituents of the fuel have their percentages recalculated on a 100 percent
total without the ash.
ASME – is the American Society of Mechanical Engineers.
Bagasse – fuel produced as by-product of the sugar cane industry. It is the material left
after the juice has been extracted from sugar cane by the mill rolls. Its use is
limited to tropical and semitropical counties, in which the sugar can is grown.
The heat value of bagasse is from 3,350 to 4,090 B.t.u. per pound, and the
moisture content is about 32 per cent. Ref. "Boiler Fuels and Trials" by A. S.
Callen, pub. International Textbook Co. 1933
Banking – is the burning of solid fuel on a grate at rates sufficient to maintain ignition
only.
Blast furnace gas – is a gas the result of burning coke with insufficient air. A low
calorific value gas results, and is byproduct of a blast furnace.
Blow torch effect - when the flame impinges on any surface, such as a tube, or
refractory wall, that surface is burned as by a blow torch.
Bowling hoop – is a furnace stiffener that also allows for differential expansion
between the furnace and the shell.
Briquets - are blocks of compressed fuel made usually from waste material or from
natural fuels that are hard to burn in their original state. They may be made from
sawdust, peat, lignite, anthracite or bituminous screenings, or fine coke. Their
heat value depends on that of the material of which they are made.
BTU – is a British thermal unit. The mean value is 1/180th of the heat required to raise
one pound of water from 32 oF to 212 oF at a constant atmospheric pressure. It is
approximately equal to the heat required to raise one pound of water by 1 degree
Fahrenheit of 1053.35 J (251.997 cal)
Caking coals – is a coal that becomes soft under the usual furnace temperatures and
merges into an undesirable mass of coke. These coals cause considerable
trouble in underfeed or chain-grate stokers by clogging air-supply or tuyeres.
CMIF – Cylindrical Multi-tubular Internally Fired
CT- Cross type- water tube boiler developed by Babcock and Wilcox
CTM- Babcock and Wilcox marine water tube boiler.
LPB – is a Low-pressure boiler. Refer EN 12953:2002
NDT – Non Destructive Testing
Once through boiler – is a steam generator that is usually operated above the critical
pressure. There is no recirculation of the working fluid. There is a constant
increase in temperature and enthalpy from the inlet to the outlet.
Peat - is the organic matter or vegetable soil of bogs, swamps, and marshes--decayed
mosses, coarse grasses, etc. The peat next to the surface, less advanced in
decomposition, is light, spongy and fibrous, of a yellow or light reddish-brown
color; lower down it is more compact, of a darker-brown color , and in the lowest
strata it is of a blackish brown, or almost a black color, of a pitchy or onctuous
feel. Ref. "Maxims and Instructions for The Boiler Room" by N. Hawkins pub.
Audel, 1902.
Proximate analysis – the analysis of a solid fuel determining the moisture, volatile
matter, fixed carbon, and ash; expressed as a percentage of the total mass.
PF – Pulverized fuel
PQR – Procedure qualification record in ASME IX. Referred to as WPAR in Europe.
Pulverized fuel – solid fuel reduced to a fine size such as 70 percent through a 200mesh screen. The size of the fuel is such that it may be burnt in suspension.
SAFed – is the Safety Association Federation. Based in the UK
Straw – is a form of refuse that can be burned in a properly designed combustor. The
heat value of straw is about 6,290 B.t.u. per pound, and the moisture content 15
per cent. Ref. "Boiler Fuels and Trials" by A. S. Callen, pub. International
Textbook Co. 1933
TAN - Tan, or oak bark, after having been used in the process of tanning is burned as a
fuel. The spent tan consists of the fibrous portion of the bark. Five parts of oak
bark produce four parts of dry tan. Ref. "Maxims and Instructions for The Boiler
Room" by N. Hawkins pub. Audel, 1902.
Tan bark has an approximate heat value of 2,650 B.t.u. per pound and a
moisture content of about 65 per cent. Ref. "Boiler Fuels and Trials" by A. S.
Callen, pub. International Textbook Co. 1933
WATC – is the welders approval test certificate. Known as the WPQ the welders
performance qualification.
W.I.F.- wrought iron fronted- type of water tube boiler supplied by Babcock and Wilcox.
Wiskey - a drink that boiler operators use during cold winters night shifts.
WPQ – is the welders performance qualification. Known as the WATC in Europe
WPAR – is the weld procedure approval record. Also known as PQR or procedure
qualification record
WPS – Weld Procedure Specification
Last update – 6 August 2003