Browse by letter:
A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
N |
O |
P |
Q |
R |
S |
T |
U |
V |
W |
X |
Y |
Z
| Term | Definition |
|---|---|
| Packaged Boiler | A boiler supplied with all of its components - burner, controls and auxiliary equipment, designed as a single engineered package, and ready for on-site installation. |
| Packaged Steam Generator | See Packaged Boiler. |
| Particle Size | A measure of dust size, expressed in microns or per cent passing through a standard mesh screen. PASS - A confined passageway, containing heating surface, through which a fluid flows in essentially one direction. |
| Perfect Combustion | The complete oxidation of all the combustible constituents of a fuel, utilizing all the oxygen supplied. |
| Petroleum | Naturally occurring mineral oil consisting predominately of hydrocarbons. |
| pH | The hydrogen ion concentration of a water to denote Acidity or Alkalinity. A pH of 7 is neutral. A pH above 7 denotes alkalinity while one below 7 denotes acidity. This pH number is the negative exponent of 10 representing hydrogen ion concentration in grams per liter. For instance a pH of 7 represent 10-7 grams per liter. |
| Pilot | (See also "Ignitor.") A flame which is utilized to ignite the fuel at the main burner or burners. |
| Pitot Tube | An instrument which will register total pressure and static pressure in a gas stream, used to determine its velocity. |
| Pitting | A concentrated attack by oxygen or other corrosive chemicals in a boiler, producing a localized depression in the metal surface. |
| Port | An opening through which fluid passes. |
| Post Purge | A method of scavenging the furnace and boiler passes to remove all combustible gases after flame failure controls have sensed pilot and main burner shutdown and safety shut-off valves are closed. |
| ppm | Abbreviation for parts per million. Used in chemical determinations as one part per million parts by weight. |
| Precipitate | To separate materials from a solution by the formation of insoluble matter by chemical reaction. The material which is removed. |
| Precipitation | The removal of solid or liquid particles from a fluid. |
| Preheated Air | Air at a temperature exceeding that of the ambient air. PRESSURE - Force per unit of area. |
| Pressure Drop | The difference in pressure between two points in a system, caused by resistance to flow. |
| Pressure Vessel | A closed vessel or container designed to confine a fluid at a pressure above atmospheric. |
| Primary Air | Air introduced with the fuel at the burner. |
| Priming | The discharge of steam containing excessive quantities of water in suspension from a boiler, due to violent ebullition. |
| Process Steam | Steam used for industrial purposes other than for producing power. |
| Products of Combustion | The gases, vapors, and solids resulting form the combustion of fuel. |
| Pulsation | Rapid fluctuations in pressure. |
| Purge | To introduce air into the furnace and the boiler flue passages in such volume and manner as to completely replace the air or gas-air mixture contained therein. |
