www.powerhouse.com
customer login | employee login | espanol
1-800-37-STEAM Contact Us
Acid Cleaning
The process of cleaning the interior surfaces of steam-generating units by filling the unit with a dilute acid accompanied by an inhibitor to prevent corrosion and by subsequently draining, washing, and neutralizing the acid by a further wash of alkaline water.
Air vent
A valve opening in the top of the highest drum of a boiler or pressure vessel for venting air.
Air-atomizing oil burner
A burner for firing oil in which oil is atomized by compressed air which is forced into and through one or more streams of oil, breaking the oil into a fine spray.
Air-fuel ratio
The ratio weight, or volume, of air to fuel.
Air-purge
The removal of undesired matter by replacement with air.
Alkalinity
The amount of carbonates, bicarbonates, hydroxides, and silicates or phosphates in the water; reported as grains per gallon, or parts per gallon, or parts per million as calcium carbonate.
Allowable working pressure
The maximum pressure for which the boiler was designed and constructed; the maximum gauge pressure on a complete boiler; and the basis for the setting on the pressure relieving devices protecting the boiler.
Atomization
The process whereby a volume of liquid is converted into a multiplicity of small drops. The principal goal is to produce a high surface area to mass ratio so that the liquid will vaporize quickly and thus be susceptible to combustion.
Atomizer
Part of an oil gun which breaks up the fuel oil flow into tiny particles by both mechanical means and the use of an atomizing medium. The oil and atomizing medium mix together in the atomizer and then flow to the oil tip to be discharged into the furnace.
Automatic lighter or igniter
A means for starting ignition of fuel without manual intervention. Usually applied to liquid, gaseous or pulverized fuel.
Available draft
The draft which may be utilized to cause the flow of air for combustion or the flow of products for combustion.
Backing ring
A strip of thin plate used on the inner surfaces of the abutting ends of pipes, tubes, or plates which are butt-welded. Its purpose is to prevent irregularities at the base weld and to permit penetration at its root.
Baffle
A plate or wall for deflecting gases or liquids.
Balanced Draft
The maintenance of a fixed value of a draft in a furnace at all combustion rates by control of incoming air and outgoing products of combustion.
Barometric pressure
Atmospheric pressure as determined by a barometer usually expressed in inches of mercury.
Base load
The term applied to that portion of a station or boiler load that is practically constant for long periods.
Blast furnace gas
Lean combustible by-product gas resulting from burning coke with a deficiency of air in a blast furnace.
Blowback
The number of pounds per square inch of pressure drop in a boiler from the point where the safety valve pops to the point where the safety valve reseats.
Blowback ring
An adjustable ring in a safety valve, used to control the amount of blowback.
Blowdown
The drain connection including the pipe and the valve at the lowest practical part of a boiler, or at the normal water level in the case of a surface blowdown. The amount of water blow down.
Blowdown valve
A valve generally used to continuously regulate concentration of solids in the boiler, not the drain valve.
Blower
A fan used to force air under pressure.
Boiler
A closed vessel in which water is heated, steam is generated, steam is superheated, or any combination thereof, under pressure or vacuum by the application of heat from combustible fuels, electricity, or nuclear energy. The term does not include such facilities of an integral part of a continuous processing unit but does not include fired units of heating or vaporizing liquids other than water where these units are separate from processing systems and are complete within themselves.
Boiler header (box)
A pressure part of the boiler consisting of a flat tube sheet into which the ends of the water tubes are rolled. In a parallel plane is a tube cap or handhole sheet. The two sheets are spaced about 4 to 8 in. or more apart. The top and bottom and both ends are flanged together and riveted or may be closed by a narrow strip of plate riveted to each sheet. Circulating nipples connect the top of the header and drum, or the header may be flanged and riveted directly to the drum. Welding would be used today instead of rivets.
Boiler horsepower
The evaporation of 34 1/2 lbs. of water per hour from a temperature of 212oF into dry saturated steam at the same temperature. Equivalent to 33,475 Btu.