WORD | DEFINITION |
ALLOY STEEL | A steel which owes its distinctive properties to elements other than carbon. |
ANSI | American National Standards Institute |
API | American Petroleum Institute |
APPURTENANCES | components or apparatus belonging to something larger or more important |
AREA OF A CIRCLE | The measurement of the surface within a circle. To find the area of a circle, multiply the product of the radius times the radius times Pi (3.142). |
ASME | American Society of Mechanical Engineers |
ATMOSPHERIC TESTING EQUIPMENT | a calibrated direct-reading instrument for testing various potential hazardous atmospheric conditions in a confined work space |
BACKFLOW PREVENTER | a device or a method that prevents a reverse flow from the normal direction of flow in a piping system |
BACK-PRESSURE VALVE | a valve which prevents excessive back pressure in an exhaust steam piping system |
BAG HOUSE | enclosure through which dust particles are collected as exhaust gases pass through a fabric filter |
BALANCING VALVE | valve used on hydronic systems to give each circuit the same pressure drop due to friction loss |
BLAST FURNACE | a smelting furnace into which compressed hot air is driven to complete the first stage in the production of all iron-based metals |
BLOWDOWN | a connection at the bottom or lowest portion of a gauge glass, low water cutoff, automatic water feeder, cast iron water column, etc., to facilitate cleaning out or testing of the equipment |
BLOWOFF | a connection tied in at the lowest possible level of the water section of a steam boiler and at the boiler water line to enable boiler drainage or removal of sludge, mud, scale, etc. |
BLOWOFF TANK | a device or apparatus used to receive boiler blow off for the purpose of cooling the water temperature to 170oF |
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 |
BOILER FEED WATER | see feed water |
BOILER HEATING SURFACE | the area of the heat transmitting surface within a boiler which is in contact with water (or steam) on one side and products of combustion (hot gases) and/or radiant heat from fire on the other side (direct heating surface [radiant], indirect heating surface [hot gases]) |
BOILER TRIM | the controls, equipment and accessories connected to a boiler for its safe and efficient operation |
BOLT-TENSIONING EQUIPMENT | a power-assisted mechanical device used to tighten fasteners to a pre-determined torque value. May also be used in reverse to loosen fasteners |
BOOM | the main member used to carry the hoisting tackle on a crane |
BRAZE WELD OR BRAZING | A process of joining metals using a nonferrous filler metal or alloy the melting point of which is higher than 800 degrees F(427 degrees C) but lower than that of the metals to be joined. |
BREECHING (GAS FLUE) | a passage for gas flow |
BUTT FUSION | a joining method that requires ends of pipe to be joined by direct heat application on material such as steel or plastic |
BUTT WELD | A circumferential weld in pipe fusing the abutting pipe walls completely from inside wall to outside wall. |
BYPASS VALVE | manual controlled passage around a controlling device |
CAD | Computer-Aided Drafting, Computer-Aided Design; used for drawing, altering and recalling views and details on a computer |
CARBON ARC CUTTING | an arc cutting process in which metals are severed by melting them with the heat of an arc between a carbon electrode and the base metal |
CARBON STEEL | A steel which owes its distinctive properties chiefly to the various percentages of carbon (as distinguished from the other elements) which it contains. |
CATALYST | an additive that initiates a chemical reaction that causes resin to harden (i.e., MEKP) |
CHAIN FALLS | hand/pneumatic/electric-operated chain hoist |
CIRCUIT | the piping path from a boiler or heat exchanger to a heat transfer unit and back to the boiler, e.g. on a monoflow system each rad has a circuit |
CIRCUMFERENCE OF A CIRCLE | The measurement around the perimeter of a circle. To find the circumference, multiply Pi (3.142) by the diameter. |
COEFFICIENT OF EXPANSION | A number indicating the degree of expansion or contraction of a substance. The coefficient of expansion is not constant and varies with changes in temperature. For linear expansion it is expressed as the change in length of one unit of length of a substance having one degree rise in temperature. |
COKE OVEN | tightly sealed unit to keep out air so coal cannot burn, rather it “bakes” with an intense heat up to 2100°F to produce coke |
COME-ALONG | rachet-type tool with chain and hook used for pulling |
CONDENSATE RETURN SYSTEM | a piping arrangement designated to return condensate to a steam generator |
CONFINED SPACE | an area other than an underground working that a) is enclosed or partially enclosed, b) is not designed or intended for continuous human occupancy, c) has limited or restricted means for entry or exit that may complicate the provision of first aid, evacuation, rescue or other emergency response service, and d) is large enough and so configured that a worker could enter to perform assigned work |
CONTOUR MARKER | instrument used in the fabrication of pipe that will trace lines for the cutting of Ts, Ys and laterals |
CONTROL VALVE | a globe-type valve which controls the flow of a liquid or gas automatically as directed by an electrical or pneumatic signal or a capillary tube; it may be a single or double seated valve |
CONTROLLER | attempts to regulate a measurement at some preselected valve; may also indicate or record, e.g. recorder-controller |
CONVERTER | a piece of equipment used to heat or cool water and other liquids by means of steam, high temperature hot water, or chilled water without the two mediums coming in contact with each other (heat exchanger; indirect heater) |
CORROSION | The gradual destruction or alteration of a metal or alloy caused by direct chemical attack or by electromechanical reaction. |
CREEP | The plastic flow of pipe within a system; the permanent set in metal caused by stresses at high temperatures. Generally associated with a time rate of deformation. |
CSA | Canadian Standards Association |
CYCLONES | any of certain centrifugal devices for separating solid material from gases or liquids |
DEAERATOR | a device used to heat the feedwater before it enters the steam boiler. It may be used for reducing thermal shock, saving of fuel, removing temporary hardness and unwanted gases (such as oxygen and carbon dioxide) from the make-up water |
DESUPERHEATER | a device which uses water as a cooling medium to lower the temperature of the superheated steam |
DIAMETER OF A CIRCLE | A straight line drawn through the center of a circle from one extreme edge to the other. Equal to twice the radius. |
DIGESTER | vessel used in the pulping and recovery process |
DIGITAL | providing a readout in numerical digits |
DIRECT RETURN | a two-pipe heating system (hydronic systems) in which the first unit supplied has the shortest return to the boiler |
DIRT POCKET | a short piece of pipe and a cap in which scale, dirt or any other foreign matter may gather and which prevents their entry into an automatic control, usually a steam trap |
DOG | a tool used in fitting up plate |
DOUBLE-BLOCK-AND-BLEED | a valving system wherein a full flow vent valve is located on piping between two shut-off valves in series for the purpose of bleeding to the atmosphere excess pressure between valves |
DOWN COMER | a tube or pipe in a boiler or vessel circulating system through which fluid flows downward |
DRIP | a piping arrangement by which condensate accumulation is handled or removed in a steam system |
DUCTILITY | The property of elongation, above the elastic limit, but under the tensile strength. A measure of ductility is the percentage of elongation of the fractured piece over its original length. |
DUCTWORK | a passage for air flow |
DYE PENETRATION TEST | a process which involves the use of three non-corrosive liquids. First, the surface cleaning solution is used. Then the penetrant is applied and allowed to stand for 10 minutes. The penetrant is removed with the cleaner solution and the developer is applied. The dye penetrant, which has remained in the surface discontinuity, will be drawn to the surface by the developer, resulting in bright red indication. |
ELASTIC LIMIT | The greatest stress which a material can withstand without a permanent deformation after release of the stress. |
EQUALIZING (BAR) BEAM | bar or beam used to equalize the loads in sling legs or to equalize loads on dual hoist lines during tandem lifts |
EROSION | The gradual destruction of metal or other material by the abrasive action of liquids, gases, solids or mixtures thereof |
ESW | electro-slag welding |
EXPANSION JOINT | a manufactured, mechanical device to take up or to compensate for the expansion and contraction of a pipe line due to temperature change |
EXPANSION JOINT | a joint to permit movement due to expansion without undue stress |
FCAW | flux-cored arc welding |
FEED WATER | water that is fed into a boiler |
FERROUS | metals dominated by iron in their chemical composition (i.e., carbon and low alloy steels) |
FIBERGLASS | glass reinforcement material (i.e., chopped strand mat, woven roving) |
FLASH TANK | a device or apparatus used to cool high temperature condensate to a low enough temperature to prevent it from flashing in a low pressure return |
FLASHBACK | flashback always occurs in the line carrying the lower pressure and will always occur beyond the mixer, and may include the hose and regulator as well. It is usually a devastating explosion or series of explosions, leaving the equipment in shambles |
FLASHING (FLASH STEAM) | the act of water changing to steam. Steam which is formed when hot condensate under pressure is released to a lower pressure |
GMAW | gas-metal arc welding |
GRID LINES | a pattern regularly spaced horizontal and vertical lines forming squares on a set of architectural drawings, used as a reference for locating points |
GTAW | gas tungsten arc welding |
HEAT EXCHANGER | a vessel in which heat is transferred from one medium to another |
HEAT EXCHANGERS | a device for transferring heat from one fluid to another without intermixing the two fluids. |
HEAT TRANSFER UNIT | a device used to transfer heat from a fluid to a space for conduction, convection or radiation |
HIGH TEMPERATURE HOT-WATER SYSTEM | a system which has hot water above 350oF |
HVAC SYSTEM | heating, ventilation and air-conditioning system |
HYDROSTATIC TEST | a strength and tightness test of a closed pressure vessel by water pressure |
INDICATOR | an instrument that shows a measurement, but makes no permanent record, e.g. pressure gauge |
INTERFERENCE DRAWINGS | plan and elevation drawings for structural, civil and HVAC among others; used in conjunction with pipe drawings in an effort to identify conflicts or interferences may also be known as coordination drawings |
INTERNALS | components or apparatus inside vessel |
ISOLATORS | a device used to isolate equipment from its piping for testing or flushing purposes; isolators are also used to give separation from its support to prevent the transmission of noise and/or vibration |
LASER | visible or infrared light used for levelling or alignment |
LASHING | a rope wrapping two pieces to fasten them together |
LATTICE BOOM | a type of framework crane boom, usually raised or lowered by wire rope mechanisms |
LAY-UP | fabrication or repair of fiberglass components |
LOW ALLOY STEEL | a ferrous metal with improved mechanical and physical properties compared to plain carbon steel commonly used to fabricate pressure vessels |
LOW WATER CUTOFF | a device which shuts off the automatic fuel control valve when the water falls below a safe level in the boiler |
MAGNETIC PARTICLE TEST | a non-destructive method of detecting cracks, porosity, seams, inclusions, lack of fusion and other discontinuities in ferromagnetic materials in surface discontinuities and shallow subsurface only |
MAKE-UP WATER | water supplied to a system that replaces system fluid that has been lost through evaporation, leakage, etc. |
MASS | metric equivalent of weight, usually expressed in kilograms or tonnes |
MEDIUM TEMPERATURE HOT-WATER SYSTEM | a hot-water heating system which has a supply temperature between 250oF and 350oF |
METALLURGY | involves the science of producing metals from ores, of making and compounding alloys, and the reaction of metals to many different activities and situations |
MSDS | Material Safety Data Sheets |
MTR | Mill Test Report |
NITROGEN TEST (PURGE) | involves using a gas heavier than air to displace oxygen in an enclosed space |
NON-FERROUS | metals that do not contain iron in their chemical composition (e.g., aluminum, copper) |
ORIENT | to set or arrange to a determined position |
OUTRIGGERS | extendable beams attached to a crane base mounting that rest on supports at the outer ends and provide a means of balancing the load and relieving the crane weight from the tires |
OXY-FUEL CUTTING | a group of cutting processes used to sever metals by means of the chemical reaction of oxygen with the base metal at elevated temperatures. The necessary temperature is maintained by means of gas flames obtained from the combustion of a specified fuel gas and oxygen. |
PARTS OF LINE | the number of individual ropes supporting a travelling block in a tackle system |
PENSTOCK | conveys water from the reservoir to the spiral case |
PIN INDEXING | refers to a fail-safe design by which end connections for specific gasses can only be connected to other ends intended for use with the same gas; for example, equipment intended to utilize oxygen cannot physically be connected to a nitrous oxide gas supply |
PLASMA-ARC CUTTING | an arc cutting process that severs metal by melting a localized area with a constricted arc and removing the molten material with a high velocity jet of hot, ionized gas issuing from the orifice |
POST HEATING | use of heat source to heat an area after a process such as welding takes place |
PPE | personal protective equipment |
PRECIPITATOR | an ash separator and collector of the electrostatic type |
PREHEATING | use of heat source to heat an area before a process such as welding takes place |
PRESSURE-REDUCING VALVE | a device of a globe valve pattern used to reduce steam pressure from a higher to a lower pressure; they may be single- or doubled-seated; a device of a globe valve pattern used to reduce city water pressure to the minimum desired system pressure (hot-water system) |
PROMOTER | an additive used with rapid cure resins to reduce excessive exothermic heat build up |
RADIUS OF A CIRCLE | A straight line drawn from the center to the extreme edge of a circle. |
RECEIVER | receives the signal from a transmitter and converts it into a measurement; may be recording or indicating and may control, e.g. receiver recording controller |
RECORDER | makes a permanent record of measurement |
REEVE | the act of passing a rope through a number of sheaves in a multi-part system in order to gain mechanical advantage |
RESIN | a bonding agent used in the fibreglass process; used in the pulp and paper industry because of its resistance to acids and alkalines |
RESIN | a polyester (vinylester) solid usually dissolved in styrene, but when mixed with a catalyst, forms a rigid thermoset plastic |
ROPE | refers to wire rope unless otherwise specified |
SAFETY RELIEF VALVE | a safety device that will open before a dangerous pressure is reached |
SATURATED STEAM | steam which is at the same temperature as the boiling water from which it was formed (dry saturated; wet saturated) |
SAW | submerged arc welding |
SCRUBBER | an apparatus used to remove solids from gases by entrainment in water |
SELF-PROPELLED LIFT | a power-propelled work platform with the primary controls on the platform (i.e., scissor lift) |
SHACKLE | a u- or anchor-shaped fitting with pin |
SHEAVE | a wheel or pulley with a circumferential groove designed for a particular size of wire rope; used to change direction of a running rope |
SINGLE-SEATED CONTROL VALVE | a control valve with a single seat and a single plug or disc |
SLING | a wire rope or other material with eyes spliced on each end |
SMAW | shielded metal-arc welding |
SOCKET FITTING | A fitting used to join pipe in which the pipe is inserted into the fitting. A fillet weld is then made around the edge of the fitting and the outside wall of the pipe. |
SOLDERING | A method of joining metals using fusable alloys, usually tin and lead, having melting points under 700 degrees F(371 degrees C). |
SOLVENT FUSION | joining plastic pipe by the use of a solvent which dissolves the surface of the pipe and forms a continuous bond upon evaporation |
SOOT BLOWER | a device which blows the soot off the tubes in the boiler with the use of steam |
SPLICE | the joining of ends of ropes by weaving the strands of one rope over and under the strands of the other rope |
SPOOL SHEETS | detail views of a piping system identifying specific piping and closing pieces to be fabricated |
SPREADER BAR | a bar that keeps a set of slings from closing up around a piece of equipment and doing damage when in the process of lifting |
SPREADER BEAM/BAR | beam used for hoisting trusses or long loads; also used to equalize the weight and to keep the load, such as tank plate, from buckling |
SPREADERS | a set of chokers or slings of equal length used to lift a load |
STACK | a vertical conduit used to discharge combustion products to the atmosphere |
STEAM SEPARATOR | a device used to remove entrained moisture present in steam |
STEAM TRACING | a small tube, 3/8 in. – 5/8 in., which is wrapped around pipe, vessels and pumps and is filled with steam to keep liquids in them from freezing |
STEAM TRAP | an automatic device which allows the passage of air and condensate but prevents the passage of steam |
STOVE | used to heat air to speed combustion |
STRAIGHTENING VANES | a device used to take the turbulence out of liquids and gases flowing in pipes so measuring instruments can get an accurate reading |
STRAIN | Change of shape or size of a body produced by the action of a stress. |
STRESS | The intensity of the internal, distributed forces which resist a change in the form of a body. When external forces act on a body they are resisted by reactions within the body which are termed stresses. |
STRESS RELIEVING (BY HEAT) | a process of heating a fabricated piece of equipment to a high temperature to relieve any stress caused from welding the metal together |
STRESS, COMPRESSIVE | One that resists a force tending to crush a body. |
STRESS, SHEARING | One that resists a force tending to make one layer of a body slide across another layer. |
STRESS, TENSILE | One that resists a force tending to pull a body apart. Stress Torsional: One that resists forces tending to twist a body. |
SUPERHEATED STEAM | saturated steam with the addition of sensible heat; an increase in temperature of saturated steam without an increase in pressure |
SUPERHEATER | a device used to reheat dry or wet-saturated steam and increase the temperature without increasing the pressure of the steam |
SWING STAGE | a suspended scaffold |
TACKLE | an assembly of ropes and sheaves arranged for lifting, lowering and pulling |
TAG LINE | a length of rope used to control a load during lifting or lowering |
TAKE-OFFS | small pipes coming from a common larger header or pipe |
TEMPERATURE DROP | the difference in boiler temperature and return temperature from any circuit; in a hydronic system it is the difference in temperature between any two parts of the system |
TENSILE STRENGTH | The maximum tensile stress which a material will develop. The tensile strength is usually considered to be the load in pounds per square inch at which a test specimen ruptures. |
THERMAL SPRAY | process of depositing molten metal, alloy and ceramic coatings on prepared surfaces in order to build up surfaces worn down by heat, oxidation and chemical environments |
THRUST-OUT BEAM | a manufactured beam used to support a swing stage; fitted with a number of counter-weights and secured by tiebacks to solid anchorages |
TOWER CRANE | a power-operated fixed or slewing tower that provides elevation and support for its jib |
TRAY | found internally inside crude towers |
TUBE EXPANDING | the pressure-tight joint formed by enlarging a tube end in a tube seat |
TUGGER | a power source for hoisting or moving, usually consisting of a cable drum with gear-reduction unit for hand operation or with power drive |
TURBULENCE | Any deviation from parallel flow in a pipe due to rough inner walls obstructions or directional changes. |
VACUUM BOX TEST | a non-critical test designed to find leaks in welded lap joints of storage tank floor. Soapy water is applied to the joint, then the air is removed from the sealed see-through box creating a vacuum and exposing the leaks. |
VACUUM PUMP | a device used to lower atmospheric pressure inside a vessel or piping system, it is highly efficient and needs a water seal to produce near-perfect vacuum |
VELOCITY | Time rate of motion in a given direction and sense usually expressed in feet per second. |
VESSEL | a cylindrical or spherical container with closed ends designed to contain liquids, gases, or solids |
VIBRATION COMPENSATOR | a device used to isolate vibration and/or noise from transmitting or being carried from pump, motor, etc., into a piping system (noise compensator; isolator) |
VOLUME OF A PIPE | The measurement of the space within the walls of the pipe. To find the volume of a pipe multiply the length (or height) of the pipe by the product of the inside radius times the inside radius times Pi (3.142). |
WATER CUTTING | a process of using a jet of water under high pressure to sever through a variety of construction materials |
WATER LEVEL | an instrument used to determine the level of an object by means of the surface water in a tube |
WELDING | A process of joining metals by heating until they are fused together or by heating and applying pressure until there is a plastic joining action. Filler metal may or may not be used. |
WET RETURN | a steam condensate return line which is carrying only condensate |
WRAP-AROUND | a coil of gasket material used to wrap around pipe, when in the process of marking a square cutoff line |
YIELD STRENGTH | The stress at which a material exhibits a specified inciting permanent set. |