The mass of moisture (i.e. water vapour) present in one kilogram of an air/moisture mixture. The measurement unit for absolute humidity is kg/kg.
The pressure of a fluid measured above a perfect vacuum (which has zero absolute pressure). If the pressure of the atmosphere is 101 kPa absolute, this is 101 kPa above absolute zero. The pressure indicated on a pressure gauge can be converted to absolute pressure by adding atmospheric pressure to the gauge reading.
The temperature at which all molecular motion ceases. This occurs at the zero point on the absolute temperature scale, which is at 0 Kelvin. This is equivalent to minus 273.16 degrees on the Celsius scale.
A substance that is capable of extracting into itself one or more of the constituents from another gas and/or liquid mixture. Usually, the absorbent undergoes a physical or chemical change during the extraction. An example is the chemical, amine, which can absorb hydrogen sulphide from raw natural gas.
The process by which some of the atoms, molecules or ions of a gas or liquid mixture are brought into (i.e absorbed by) a different solid or liquid. Absorption often involves a chemical reaction.
The process where exhaust steam and a pump is used in place of the refrigeration compressor.
A vertical, cylindrical pressure vessel in which two fluids contact each other and one fluid absorbs certain constituents from the other. An example is the contactor in a gas sweetening system, which uses amine to absorb hydrogen sulphide and carbon dioxide from raw natural gas.
A type of safety device, located between the evaporator and the compressor, used to reduce the liquid refrigerant carryover flow to the compressor suction.
A colourless gas (C2H2) prepared by the action of water with calcium carbide. Acetylene is used in gas welding and cutting.
A substance that, when dissolved in water, produces a solution containing hydrogen ions (H+). A substance capable of donating a proton (+) to another substance. The strength of an acid is determined by its pH value.
A chemical pulping process that uses an acidic calcium sulphite solution plus heat to break the bonds in wood between the cellulose and the wood fibres.
Any gas that contains a significant amount of constituents that may form acids when mixed with water. An example is the acid gas, consisting largely of hydrogen sulphide and carbon dioxide, created in the process of sweetening natural gas.
In water: the excess of hydrogen ions (H+) over hydroxide ions (OH-) that occurs where the pH is less than 7.
A form of aluminium oxide that readily absorbs moisture and is commonly used as a drying agent. For example, wet instrument air may be passed through a bed of activated alumina pellets, where the alumina removes the moisture from the air.
The quantity of inlet air (i.e free air, at the conditions of temperature and pressure existing at the inlet) delivered by an air compressor. This quantity is expressed in cubic meter per minute.
A solid substance with surface areas that are capable of extracting one or more constituents from a mixture of gases and/or liquids by the physical attraction of the extracted material onto the surface areas. No physical or chemical change of the adsorbent results.
The physical attraction and binding of atoms, molecules or ions of one substance onto the surface of another substance.
A heat exchanger that removes the heat of compression from the air (or other gas) after it leaves the last stage of a compressor.
The coming together of small, scattered particles into larger, heavier particles, called floc, which are then able to settle easier and faster out of a liquid. Refer to *Floc*.
The simultaneous control of the physical and the chemical conditions of the atmosphere within a structure. This is achieved by affecting some or all of the following air conditions: temperature, humidity, motion, distribution, pressure, dust, bacteria, odours, toxic gases, and ionization.
A device, usually at the ceiling, used for the distribution of the conditioned air from the terminal of the air duct(s).
In an electrical machine, the space between the rotor and stator across which magnetic lines of flux must travel through air.
A heat exchanger, located near the flue gas exit of a boiler, which transfers heat from the flue gas to the combustion air entering the boiler. This preheating of the air improves the combustion efficiency.
A heat exchanger which uses a natural or forced flow of ambient air around the outside of a set of tubes to cool and condense a vapour contained inside the tubes.
The amount of combustion air, in kg, supplied to a boiler for each kg of fuel burned. Expressed as a ratio it is "kg of air/kg of fuel".
The position of one piece of equipment relative to another. An example is the "alignment" of the shaft of motor with the shaft of the pump that the motor is driving.
A soluble salt, principally of sodium, potassium, magnesium, and calcium, that has the property to combine with acids to form neutral salts.
A chemical pulping process that uses an alkaline cooking liquor, caustic soda, plus heat to break the bonds in wood between the cellulose and the wood fibres.
The capacity of water to neutralize acids. This capacity is caused by the water's content of carbonate, bicarbonate, hydroxide, and occasionally borate, silicate and phosphate.
The maximum internal stress that a structural metal may be subjected to under normal operating conditions. This stress is determined by dividing the ultimate stress (i.e the stress at which the metal will break) by a factor of safety.
A metal that is produced by mixing certain metals with a base metal for the purpose of achieving improved qualities over the base metal. An example is stainless steel, which has more chromium in it than carbon steel.
That part of the sine wave cycle in which the emf or current value rises from zero to a maximum and reduces back to zero again in one direction. An alternation is one half of a cycle.
Arithmetic Logic Unit, a computer component where all arithmetic and logical operations are performed.
The part of the gas sweetening process that separates the sour gas from the amine solution so the amine can be reused.
A computer in which numerical data are represented by continuously variable measurable physical properties, such as electrical signals.
A situation in which the center lines of the two shafts are at an angle to each other in either a horizontal or vertical position.
A hot water boiler fitting that controls the starting and stopping of the burner by sensing the temperature of the water.
A group of welding processes that produce the coalescence of metals by heating them with an arc with or without the application of pressure and with or without the use of filler metal.
A computer component where all arithmetic and logical operations are performed.
The conductors of a generator in which emf is induced or the conductors of a motor in which torque is produced.
The effect caused by the interaction of the magnetic field of the current carrying conductors in the armature with the main magnetic field. The two magnetic fields combined cause a distortion in the overall magnetic field that results in a shift in the neutral plane in the direction of armature rotation.
The ability of a machine to perform those activities that are normally thought to require intelligence; also the branch of computer science concerned with the development of machines having this ability.
The manual technique of breathing for a non-breathing casualty. Also referred to as rescue breathing.
Codes developed by the American Society of Mechanical Engineers for use in design and construction in industry.
A device consisting of two thermometers mounted side-by-side, one having a bare bulb and the other having a bulb covered with fabric. A fan is used to draw air over the thermometers.
A cardiovascular condition in which there is an accumulation of cholesterol and fatty acids inside the arteries, which leads to a narrowing or hardening of the arteries.
The smallest part of an element that can exist and still retain the properties of the element; i.e. a nucleus and surrounding electrons.
A number that indicates both the number of the protons and number electrons in the atom.
An abbreviated means of identifying an element. i.e. C is the chemical symbol for the element carbon.
A high temperature crystalline phase in steel in which the crystal structure is face centred cubic.
An expansion valve actuated by changes in pressure in the evaporator to maintain a constant pressure in the evaporator.
Devices that automatically monitor for and sense the occurrence of a fire and, in some instances, will be used to extinguish the fire.
A transformer that contains only one winding that serves as both the primary and the secondary winding.
All the equipment required, such as pumps, fans, fuel supply, and others, required for the efficient and safe operation of a system.
Refers to alignment with the axis of a machine. An axial force acting on a pump shaft would be acting along the shaft.
A compressor that uses rotor blades shaped like airfoils that give the air a high velocity and push it into subsequent stationary blade passages that convert the velocity energy into pressure. This process is repeated through several stages. The airflow movement is axial.
A type of vertical turbine pump that uses a propeller instead of an impeller. The water flow is axial.
Bearing metal of non-ferrous material, containing several tin-based alloys, mainly copper, antimony, tin and lead.
A device that is installed to prevent the backwards flow of potentially contaminated water, gas, or other substance into any potable water supply or distribution piping.
A flow through a vessel in the opposite direction of normal flow employed to clean the bed material.
A wall or wall section located in the gas passage used to change the direction of the flue gas flow so maximum heat will be absorbed.
The use of forced and induced draft fans to create a furnace draft at or just below atmospheric pressure.
A holding basin in which variation in flow and composition of a liquid are averaged. Such basins are used to provide a flow of reasonably uniform volume and composition to a treatment unit.
Anti-friction bearings containing races and spherical rolling elements designed to support and locate rotating shafts or parts in machines.
An electromagnetic device used with a gas discharge lamp to control starting and operating conditions.
When an electric generating system consists of several electric generating units and where the first unit is fully loaded at a constant load, and the second generating unit may control the load demand.
Tubular hot water or steam heating elements that have aluminium fins mounted on exterior walls near the floor and covered with vented sheet metal casings.
A treatment operation in which a vessel or reactor is filled, the process is treated, and the vessel is emptied. It may then be refilled and the process repeated.
A strip or coil that consists of two different metals having different thermal expansion rates that are bonded together.
The life-supporting surroundings and its immediate atmosphere where interactions occur between the organisms and the environment.
In computer science, a single character of a language having just two characters, as either of the binary digits 0 or 1; a unit of information equivalent to the choice of either of two equally likely alternatives; a unit of information storage capacity, as of memory.
Contaminants, present in the air or the fuel, are deposited on the blades of a compressor or turbine.
The clogging of filtering medium of a micro screen or a vacuum filter when the holes or spaces in the media become sealed off due to grease or the material being filtered. Also, insertion of blind flanges into a pipeline for isolation purposes.
Valves used simultaneously to isolate a specific section of a system for maintenance or inspection of that section.
A group of pulleys on the same shaft. A continuous rope is wound over two such blocks to form a machine that will provide a mechanical advantage.
In a pulping process, a vessel that receives the solution of chips and chemicals before the solution is washed; where the steam from the digester is removed to atmosphere. The chips and chemical are blown into the vessel causing the break-up of the chips.
Valves that are opened to remove sludge and impurities from, or drain, a boiler or vessel.
An ASME code, The Boiler and Pressure Vessel Code establishes rules of safety governing the design, fabrication, and inspection of boilers and pressure vessels, and nuclear power plant components during construction.
The process of releasing a portion of the water continuously or intermittently from a boiler to remove impurities in order to maintain predetermined concentrations.
An ideal cycle in which compression and expansion take place at constant entropy, an ideal gas turbine.
A concentrated solution of a salt (NaCl) and water used in the regeneration of sodium zeolite softeners.
A solution or liquid whose chemical makeup neutralizes acids or base without great change in pH.
The action of certain ions in solution in opposing a change in hydrogen ion concentration.
A measure of the capacity of a solution or liquid to neutralize acids or bases. This is a measure of the capacity of water or wastewater for offering a resistance to changes in pH.
A solution containing two or more substances that, in combination, resist any marked change in pH following addition of moderate amounts of either strong acid or base.
In WHMIS, a shipment of a controlled product that is contained without intermediate containment or intermediate packaging.
A sequence of adjacent bits operated on as a unit by a computer; the amount of computer memory needed to store one character of a specified size, usually 8 bits for a microcomputer and 16 bits for a larger computer.
A registration number that is allotted to pressure vessel designs by the regulatory agency of the province where the design is registered.
The Canadian version of the nuclear reactor; the main difference from other reactors is the use of heavy water as a moderator and heat transfer medium.
A type of combustion chamber composed of liners located circumferentially within an annular combustion chamber case.
The property of an electric circuit to store energy by means of an electrostatic field and release it at a later time.
A device that has the ability to store electrical charge and is made of two conductive plates separated by a dielectric (insulator).
A tube of small internal diameter used as a liquid refrigerant flow control and pressure reducer between high and low pressure sides. Also used to transmit pressure from the sensitive bulb of some temperature controls to the operating element.
The force by which the liquid, in contact with a solid, is distributed between closely fitted surfaces of joints to be brazed or soldered.
A non-metallic element, symbol C, atomic number 6, atomic mass 12.01. It is a main constituent of most fuels and is added to iron in the production of steel.
A fire fighting device consisting of a cylindrical vessel containing carbon dioxide under high pressure with a release trigger and discharge horn.
Rescue breathing and chest compressions on a casualty in cardiac arrest.
A heater that uses sensible heat from the flue gas of a recovery boiler to increase the black liquor concentration to 60%.
The intercrystalline cracking of steel caused by the presence of free NaOH, stress, boiler water leakage, and concentration of NaOH.
In a pulp mill, a process used to convert the green liquor into white liquor by adding lime.
Vaporising of liquid that occurs at any point when the liquid’s pressure falls below its vapour pressure, or boiling point.
A temperature scale with gradients between the freezing and boiling points of water are divided into 100 equal parts.
When all the necessary conditioning of the air occurs in one location for distribution to a wide area.
A pump consisting of an impeller fixed on a rotating shaft and enclosed in a casing, having an inlet and a discharge connection. The rotating impeller creates pressure in the liquid by the velocity derived from centrifugal force.
Service valve used to charge or add refrigerant to the system, or add oil to the compressor crankcase.
A valve that allows flow to occur in one direction only and will close automatically if a reversal of flow occurs.
A change created when one or more new substances are produced with properties different from the original substance(s).
Potential energy stored in elements or compounds and released through chemical reactions.
Developed under the authority of the Occupational Health and Safety Act, which establishes the fundamental principles of Alberta's occupational health and safety law.
Any change that comes about through the chemical action of substances on each other, i.e. rusting and combustion are both chemical reactions involving the oxidation of a substance.
A machine designed to reduce logs to small chips of wood to supply the digester in a pulp mill.
A device designed to open a circuit and stop the flow of current when the current or voltage in the circuit exceeds a pre-set value.
A settling tank used to remove sediment from water through sedimentation, coagulation or flocculation.
A safety measure employed to ensure personnel are protected from hazards associated with dangerous equipment or areas.
The gas turbine arrangement in which the working vapour exhaust is directed back again to the compressor without coming in contact with the atmosphere.
A control system that continually monitors the process, receives feedback of process changes, and then outputs corrections to a final control element to maintain a set point value.
A closed pressure vessel associated with a hot water heating system that absorbs the variations in water volume caused by changes in water temperature.
A chemical that causes suspended matter to join together into larger particles. This makes it easier to remove the suspended matter from the liquid by settling, skimming, draining or filtering.
The use of chemicals that cause suspended matter to join together into larger particles. This makes it easier to remove the suspended matter from the liquid by settling, skimming, draining or filtering.
The change in length experienced by a solid of unit length per degree change in temperature.
A term used to describe the combination of different thermodynamic cycles for the purpose of increasing all-over cycle efficiency.
Where heat from the exhaust gases of a gas turbine is used to generate steam to drive a steam turbine.
A product, material or substance that falls into Division 3 if it has a flashpoint of 37.8°C or more but less than 93.3°C.
A rapid chemical reaction in which oxygen combines with a fuel and releases heat and/or light.
The part of the boiler or furnace where fuel is mixed with air and combustion occurs.
Refers to the passage of combustion gases over or past the heating surfaces of a boiler.
The process of preparing the air for temperature, humidity, cleanliness and distribution to meet human comfort levels.
The use of a refrigeration system to provide comfort to human occupants, rather than refrigeration used for freezing, storage, etc.
A range of temperatures at which more than 50% of the occupants in that specified area feel comfortable.
A device that converts the alternating current sine wave produced in all generator armatures into direct current at the dc generator terminals.
Where all of the combustible matter present in the fuel is oxidized and no combustible matter remains unburned.
A generator in which the field contains two sets of windings; one connected in series and the other in parallel (shunt) with the armature.
The ratio of the volume at the beginning of a compression stroke to the volume at the end.
A term used to denote increase of pressure on a fluid by the use of mechanical energy in several steps or stages.
Forces that are acting toward each other and will tend to press together or compact the body.
A machine designed for compressing air or vapour from a lower intake pressure to a higher discharge pressure.
Instability of airflow in an axial or centrifugal compressor caused by conditions of low flow and high pressure.
A series of instructions that a computer can interpret and execute; programs are also called software to distinguish them from hardware, the physical equipment used in data processing.
A device used to connect a large pipe to a smaller pipe such that the centre lines of both pipes are aligned.
Liquid formed from a vapour due to lowering of the temperature or increasing the surface pressure.
A turbine in which the steam leaving passes into a condenser operating at a pressure below atmospheric.
Hazardous products that meet certain pre-determined criteria under WHMIS guidelines.
Heat transfer via the movement of heated particles. I.e. circulation of water in a boiler.
The convention that current flows from an area of positive charge to one of negative charge. In reality the electrons, and hence the current, travel from an area of negative charge to one of positive charge.
A shell and tube heat exchanger where water flowing through tubes is heated by steam within the shell.
In electrical equipment, a material designed to conduct magnetic flux easily but offer high resistance to current. In a nuclear reactor, the area in which nuclear fission takes place and heat is produced.
An emf induced in a conductor by a change in current flow in the conductor. The cemf induced is in the direction opposite to the emf that caused the current flow.
When the fluid to be cooled flows opposite to the direction of the coolant, the coldest condition of the fluid meeting the coldest condition of the coolant.
The pressure at which the specific volume of the liquid is equal to the specific volume of its vapour.
The temperature above which it is impossible to liquefy a vapour regardless of how much pressure is applied.
Canadian Standards Association Code for the Construction and Inspection of Boilers and Pressure Vessels. Its purpose is to provide for the safe design, construction, installation, operation, inspection, testing and repair of boilers, pressure vessels, and related equipment; and second, to promote uniform requirements among the Canadian jurisdictions.
The flow of electric charge through a conductor as a result of the movement of electrons. The symbol is I and unit is the ampere.
A device used for directing and controlling a preheating flame and a supply of oxygen for cutting metal.
A complete sine wave form consisting of two alternations; first in one direction then in the other.
A type of furnace developed to burn lower grade coals, it is water cooled and insulated to maintain a high furnace temperature. Crushed coal enters with the primary air in the furnace tangentially, while the secondary air is supplied to the furnace chamber.
Separates entrained particles from the fluid steam by means of centrifugal force caused by changing direction.
A product, material or substance that meets any one of three criteria: 1) undergoes vigorous polymerization, decomposition or condensation, 2) becomes self-reactive under conditions of shock, or increase in pressure or temperature, 3) reacts vigorously with water to release a highly toxic gas.
A component used for removing dissolved oxygen or other noncondensables in boiler feed water.
The number below the line in a common fraction. If one is divided by five (1/5), then 5 is the denominator.
Any absorbent or adsorbent, liquid or solid, that will remove water or water vapour from a material. In a refrigeration circuit, the desiccant should be insoluble in the refrigerant.
The temperature at which the water vapour in the air is saturated; the temperature at which water vapour begins to condense out of the air.
A thin flexible plate held in place in a capsule in such a way that when pressure is applied to one side, the plate will bulge outward.
A pump in which a flexible diaphragm, generally of rubber or equally flexible material, is the operating part. When the diaphragm is raised suction is exerted, and when it is depress, the liquid is forced through a discharge valve.
An increasing cross-sectional area that is designed to convert high-speed fluid flow into low-speed flow at an increased pressure.
A vessel used to cook the wood and chemicals to break down the lignin that binds the cellulose fibres together.
A computer that performs calculations and logical operations with quantities represented as digits, usually in the binary number system.
The driver and driven machines (e.g. Motor and compressor) are positively connected in line to operate at the same speed.
A system in which the evaporator is either in direct contact with the material space to be refrigerated or located in the air circulating passages leading to the material space
A vessel used to dissolve the smelt from the recovery boiler into a tank of water to produce green liquor.
A group of atoms whose magnetic polarities agree and produce an overall magnetic field. A domain consists of 1014 to 1015 atoms; there are approximately 10 million domains per cubic centimeter.
A machine in which compression takes place on both strokes per revolution in each compressing element.
A system that uses flow of refrigerant from a secondary circuit to cool or condense the refrigerant of a primary circuit in an inter-cooler.
A system where the incoming domestic water supply main provides suction to a booster pump that pumps water to a storage tank located at the top of the building. Water flows downward from the tank into the domestic water system.
Mechanically driven fans used to either blow air into the furnace through the windbox or to draw the combustion gases from the boiler and expel them out the stack.
An arrangement of barriers within the cooling tower that removes condensate (water) from the air before the air exits to the atmosphere.
The vertical length of pipe connecting the bottom of the steam supply main to the return piping.
Fittings located inside the boiler drum used to separate water and steam, distribute feed water and chemicals, and provide for removal of impurities.
An extinguisher where the extinguishing agent is a dry powder and the propelling gas is either in the container in the upper chamber or on the side with a separate pressurized cartridge or canister.
An evaporator of the continuous tube type where liquid refrigerant from a pressure-reducing device is fed into one end and the compressor suction line at the outlet removes the dry refrigerant vapour.
The temperature of a gas or mixture of gases indicated by an accurate thermometer when there is no heat flow to or from the thermometer bulb.
The ratio of latent heat added in a mass of steam to the latent heat it could contain.
A gas turbine connected to one shaft driving a compressor that directs discharged gas to a second turbine, connected to a separate shaft, to drive a load such as a generator.
A pump that increases the pressure of a liquid continuously by increasing its velocity energy and then changing it to pressure energy.
A fitting used to connect a large pipe to a smaller pipe so that one edge of both pipes is aligned.
A heat recovery device used in a boiler to transfer heat in the combustion gases to feed water.
Currents caused by changing magnetic fields produced in armature and field cores of electrical machines that tend to interfere with the production of emf in the armature windings.
The ratio of a machine’s energy output to energy input. It may be expressed as a decimal or a percent. Efficiency equals the work output divided by the work input or the actual mechanical advantage (AMA) divided by the ideal mechanical advantage (IMA).
The point on a stress-strain diagram where the curve starts to deviate from a straight line and after which the material will not return to its original shape.
The property that allows a material to deform under a load and return to its original shape after the load is removed.
Boilers in which heat is produced by electricity rather than fuel oil or gas. Heat is produced either between two electrodes or by resistance to the flow of electricity through a coiled conductor.
Furnaces in which the air is heated by passing directly over the electric heating elements. Electric energy is converted to heat using open wire resistance heating elements.
Electric heaters consisting of long, slender tubes, similar in appearance to fluorescent lamp fixtures. The tubes fit into fixtures, which can be hung from the ceiling or wall, or mounted flush with the ceiling. A reflector is mounted behind each tube directs the radiant heat into the space to be heated.
The production of a chemical reaction by passing an electric current through an electrolyte.
A liquid or paste that conducts electricity as a result of the presence of positive or negative ions.
A temporary magnet made of a ferromagnetic core wound with insulated wire through which is passed an electric current. The current flow through the windings causes a magnetic field to build that will attract magnetic material.
The production of electromotive force (emf) in a conductor through relative motion of a conductor and a magnetic field, or by the change in the strength of magnetic flux around the conductor.
The potential difference, expressed in volts, that is generated by a source of electric current.
A small subatomic particle that contains a negative electric charge and is of negligible mass.
The point that a colour change occurs during titration, i.e. water testing - blue changes to clear.
The most common style of centrifugal pump, either frame-mounted or close-coupled, where the centre of the suction line is centred on the impeller eye.
The ability to do work. Energy has the same units as work (Joules) and is convertible to many different forms such as heat, mechanical, chemical, nuclear.
A theoretical resistance that is equivalent to two or more resistances in parallel.
The difference in the amount between a measured or actual value of a variable and the desired or set point value
A substance injected in the gas steam to prevent the freezing of the condensed liquid to prevent the formation of hydrates.
The water losses from a cooling tower system to the air due to evaporation. Usually expressed in %.
The production of magnetic flux by supplying electric current to the field poles of a generator to create a variable magnetic field.
The points in a process when the mediums used to perform purification are no longer able to perform their function.
A federal law that regulates any substance that is made, manufactured or used to produce an explosion or detonation or a pyrotechnic effect and includes gunpowder, propellant powders, blasting agents, dynamite, detonating cord, lead azide, detonators, ammunition, rockets, fireworks, safety flares or other signals.
The ratio of ultimate strength to allowable stress. It is used to ensure that a structural member is not subjected to excessive loads that would cause it to fail or not be able to perform the job it was designed for.
A temperature scale with graduations divided into 212 equal parts (Imperial/English system).
Any device that either shuts down or prevents the start of a machine or system when there is a drop or loss of pressure, flow or level, etc.
A machine that causes energy to be added to air or other vapours to increase its pressure or velocity.
A machine that causes energy to be added to air or other vapours to increase its pressure or velocity.
Valves installed at the outlet connections of fixtures such as sinks, that are used to control the flow of water.
The part of a closed loop system which provides the controller with information about the controlled variable for comparison to its desired value.
Treated water that is supplied to the boiler to replace the boiler water that has been converted to steam and has been removed from the boiler.
Material that contains magnetic domains that are relatively easily aligned to produce magnets. Ferromagnetic materials are iron, steel, cobalt, and alnico.
A boiler consisting of drum containing tubes through which hot combustion gases pass.
Immediate care given to a casualty at the scene of an accident prior to obtaining advanced medical support.
Devices fitted directly to a boiler or other piece of equipment that are used for safe and efficient operation.
A condition that occurs when the burner has lost its flame; also referred to as flame failure.
Any product, material or substance is included in Division 5 if it is packaged in an aerosol container and, when tested in accordance with the method set out in Schedule VI of the Controlled Products Regulations, produces a flame projection or a flashback.
A product, material or substance falls into this division if it is a Compressed Gas (Class A) and at normal atmospheric pressure forms a flammable mixture with air.
A product, material, or substance falls into Division 2 if it has a flashpoint less than 37.8°C when tested in accordance with the applicable method.
A product, material, or substance falls into Division 6 of Class B if it meets either of two conditions; 1) It is spontaneously combustible under normal conditions of use and it emits a flammable gas or 2) it becomes spontaneously combustible on contact with water or water vapour.
A product, material or substance is included in this division if it meets any one of four criteria that result in ignition.
Groups or clumps of particles or coagulants and impurities that have come together and formed a cluster. Found in aeration tanks, secondary clarifiers and chemical precipitation processes.
The emission of light energy by a substance as a result of the absorption of energy from ultraviolet radiation.
A material used to prevent, dissolve, or facilitate removal of oxides and other undesirable surface substances. Also, the measure of the quantity of magnetism, taking into account the strength and extent of the magnetic field.
These fire extinguishers use a cylindrical tank that is filled with sodium bicarbonate and an inner container with a solution of aluminium sulphate that combine to produce foam discharge.
A one-way valve placed at the entrance of a suction line that is opened by the flow of water. The purpose of the valve is to prevent reverse flow.
An action, a push or a pull, on a body that causes or tends to cause it to change its state of motion or rest, or to change its shape. (Symbol, F; unit, Newton)
The net attraction between all masses. Gravity attracts all of the particles of a mass and the net effect of this attraction at the earth's surface is equal to 9.81 Newton’s per kilogram. The force of gravity is often called weight.
A boiler draft system in which combustion air is blown or forced into the combustion chamber by a fan.
A welding process which produces the joining of metals by heating them in a forge and by applying pressure or blows.
An engine that requires two revolutions of the crankshaft to complete one working cycle.
End suction centrifugal pumps designed so that the pump bearings and pump shaft are independent of the motor. This type of pump requires a coupling between the pump and the motor in order to transfer energy from the motor to the pump.
The temperature at which a liquid will solidify or freeze upon removal of heat. The freezing point for water is 0ºC.
The number of oscillations or cycles of the sine wave produced per second expressed in Hertz (Hz).
A plunger type pump designed to inject fuel at high pressure into the cylinder of diesel engines.
A method of cutting through the whole object in order to see one of the views (top, front, right side, left side, back or bottom).
A safety device that is made up of an alloy material that is designed to melt at a specific temperature to relieve pressure in a vessel.
The application of a clamp to a safety valve, during a hydrostatic pressure test, to prevent the valve from opening.
Electromagnetic radiation emitted by atomic nuclei having less penetrating power than x-rays.
A fitting used to give a visual indication of the water level in the boiler or other vessel.
A mechanical coupling in which two shafts are connected through two gear hubs interconnected by a toothed sleeve.
An electrical machine that converts mechanical energy into electrical energy. Also, a component of an absorption system where the refrigerant is released from the absorbent.
Laws that protect people acting in good faith when administering first aid to injured or sick casualties.
A furnace where the heated air is circulated through the system by the force of gravity.
The smelt/water solution from the recovery boiler; the green colour comes from the combination of iron, sodium sulphide, sodium carbonate, and carbon.
A mechanical coupling in which a metal grid is meshed between the teeth of two shaft hubs.
A gaseous extinguishing agent that does not leave residue after discharge. It works on the principle of removing the air for combustion thus extinguishing the fire.
An opening into a boiler drum or vessel that is much smaller than the manhole and is used for cleaning and inspection purposes.
Defined in WHMIS as a controlled product that is intended for disposal or is sold for recycling or recovery.
The static pressure of a fluid expressed in terms of the height of a column of the fluid.
The ends which close off the ends of the boiler shell; may also be referred to as 'end plates' or, in fire tube boilers, as 'tube sheets'.
A form of thermal energy due to the activity of the molecules in a mass and that can be transferred from one body to another.
Anything that transfers heat from one substance to another without allowing the substances to mix.
A heat transfer device that uses the heat rejected by a refrigeration process to provide heat. A combined cooling and heating unit.
Equipment that is installed to reclaim heat that is normally lost during the blow-down process.
Parts of a boiler through which heat is transferred, from the combustion of fuel, to water or steam; the part of the boiler that has heat and combustion gases on one side and water or steam on the other.
Water used as a cooling medium in a CANDU nuclear reactor; The hydrogen atoms that make up the water have an atomic weight of 2 due to the presence of a neutron in the nucleus.
A refrigerating unit in which the compressor and compressor motor are sealed in the same housing, with no external shaft or shaft seal and the compressor motor operating in the refrigerant atmosphere.
The sections of a refrigeration system which operate at the high discharge pressure of a compressor or pump i.e. Condenser.
The highest factor in which all numbers in a group can be divided into evenly without a remainder.
Parallel or angular misalignment between two shafts as viewed from above (plan view).
A boiler completely filled with water, to which heat is applied to raise the temperature of the water, without generating any steam.
A highly toxic gas that is invisible, colourless, and flammable and has an odour like rotten eggs (sulphur).
The weight of hydrogen ion, measured in moles per litre of solution, commonly expressed as the pH value, which is the logarithm of the reciprocal of the hydrogen-ion concentration.
The pressure at the bottom of a column of liquid resulting from the height of the liquid in the column.
A pressure test on a boiler or vessel to test for leaks or strength. The vessel is completely filled with water and the pressure is 1.5 times the normal working pressure.
The resistance of the magnetic domains to change direction under the influence of a changing magnetic field.
The rotating element of a pump used to transfer mechanical energy from the pump to velocity energy in the water.
A ring attached to the impeller designed to absorb wear instead of the impeller. Also provides a seal between high and low-pressure areas of the pump.
A situation where the flame in a boiler touches or contacts the tubes or other metal surfaces. This leads to erosion of the heating surfaces.
A common fraction with the numerator equal to or greater than the denominator. (i.e. 4/3).
A turbine that uses impulse action to change heat energy in the steam to mechanical energy.
The emission of light energy from a body as a result of raising it to a high temperature.
The process of controlled burning to reduce combustible wastes to a non-combustible residue, carbon dioxide, and other gases.
A combustion chamber used to efficiently burn waste products. Also, in a gas processing plant, used to burn waste gases from the sulphur plant.
Combustion that is not complete; the products of combustion still contain combustible material.
A refrigeration system in which a secondary solution, i.e. Brine, is circulated into the air or substance to be cooled, i.e. The secondary solution flows to and from the evaporator to release the heat absorbed from the air or substance being cooled.
A boiler draft system where a fan at the boiler uptake is used to draw the flue gases from the boiler furnace.
Air that flows into a building when exterior doors are open or when air leaks in through cracks in the building envelope.
Water discharged into a sewer system and service connections from sources other than regular connections. This includes flow from yard drains, foundation drains and around manhole covers. Inflow differs from infiltration in that it is a direct discharge into the sewer rather than a leak in the sewer itself.
Information put into a communication system for transmission or into a computer system for processing; a position, terminal, or station at which input enters a system.
The devices at which or with the help of which, the information enters the computer system.
A substance that is a poor conductor of electricity as a consequence of a lack of free electrons.
A gas turbine employing two compressors, the compressed air from the first compressor is cooled before being discharged into a second compressor.
Heat exchangers that remove the heat of compression from air or gas between consecutive stages of multistage compressors.
Automatic safety switches incorporated into the boiler burner management system which will shut down the combustion process if an unsafe boiler condition exists.
An engine in which the combustion process occurs within the engine itself.
An automatically ignited pilot used to ignite the boiler main flame but is then automatically shut off while the boiler is running.
A particle, atom, or group of atoms carrying either a positive or negative charge, i.e. Na+2, SO4-2, PO4–3.
The process of adding electrons to, or removing electrons from, atoms or molecules, thereby creating ions. High temperatures, electrically discharges, and nuclear radiation can cause ionization.
The point where the wires of a thermocouple connect to the external circuit or indicating device.
A unit of electrical work where one kilowatt of power is used for one hour (3600 seconds).
The energy a body possesses by virtue of its motion. The kinetic energy of a body is directly proportional to its mass and its velocity squared.
In a refrigeration system, a service valve located between the receiver outlet and the evaporator used to isolate either component.
In TDG, diamond shaped safety marks used on packages and small containers to indicate what type of dangerous goods are inside. Also, in WHMIS, information regarding the contents, applied to containers and packages of controlled products.
Thin sheets of magnetic steel or iron that are used in armature and magnetic pole cores to reduce the production of eddy currents. The laminations increase the electrical resistance of the core material.
A metallic ring placed in a pump stuffing box that provides for the entrance of sealing and/or lubricating fluid to the packing.
Heat, added or removed, from a mass that will cause a change of state at a constant temperature.
The heat required to change a liquid to a vapour without change in temperature.
The heat quantity needed to convert a solid to a liquid without a change in temperature, i.e. 335 kJ/kg is the heat of fusion for ice.
The preparation and storage of a boiler that will be out of service for an extended period of time.
A vertical drain line on multi-story buildings employed to drain storm water into the storm sewer system.
Lower Flammability Limit - the minimum concentration of the refrigerant that is capable of propagating a flame through a mixture of refrigerant and air.
A sedimentary rock consisting mostly of calcium carbonate that is used to remove the impurities produced refining iron ore.
A force that a body or structure is subjected to. Loads may be as a result of weight such as snow on a roof, pressure such as in a boiler drum, impact such as the force on a piston during the power stroke.
Determine the amount of heat or cooling that is required to maintain a constant temperature in a building.
The turbine that is directly coupled to the load in a multi-shaft gas turbine arrangement.
A computer network dedicated to sharing data among several single-user workstations or personal computers.
The section(s) of refrigeration systems that operate at the suction pressure of the compressor or pump.
A safety device that will shut off the boiler burner operation if the water level in the boiler becomes too low.
The lowest water level in the boiler where the boiler can still be operated without damaging or overheating any part of the boiler.
A device used to control the distribution of light from a lamp. Luminaries consist of the lamp, the socket, and diffusers or reflectors.
A naturally occurring mineral (Fe3O4) that has magnetic properties such as the ability to attract other magnetic materials and is affected by the earth's magnetic field.
The part of the system that collects steam from boilers and then distributes the steam to wherever it is needed.
The valve at the steam outlet of the boiler drum on the main steam line, used to isolate the boiler.
An opening though which a person may enter the drum in order to do maintenance or inspections.
The amount of matter in a body. Mass is a constant value no matter where the body is located. The mass of an astronaut in outer space remains the same as when on earth. (Symbol: m; units: kilogram, kg).
Supplier prepared information that provides basic technical information about a product's physical characteristics and its hazardous properties.
The maximum pressure permissible at the top of the vessel in its normal operating position, at the operating temperature specified for that pressure.
The multiplication of effort that a machine provides. It permits a heavy load to be lifted by a smaller effort.
In a pulp and paper mill, where grinders are used to shred wood to produce pulp that is used mainly for newsprint.
A term describing a refrigeration system using mechanical means to transfer energy from and to a cooling medium.
A sealing device used to control leakage from the stuffing box of a pump. Mechanical seals are usually made of two extremely smooth flat surfaces, one of which rotates on a shaft. The two flat surfaces are of such close tolerances as to prevent the passage of water between them.
An electrical on-off switch using a pool of mercury to cover or uncover electrodes inside a glass tube as the tube is tilted.
Any of a class of chemical elements that are typically lustrous solids that are good conductors of heat and electricity.
A silicate material having a layered structure that is flexible and elastic. It has excellent electrical insulating properties.
A bearing for locating the axial position of a turbine rotor. It consists of a collar on a shaft with white metal faced pads mounted on either side.
A very small computer, such as a laptop or personal computer, built around a microprocessor and designed to be used by one person at a time.
An integrated circuit that contains the entire central processing unit of a computer on a single chip.
Also termed gas metal arc welding. An arc welding process that produces the coalescence of metals by heating them with an arc between continuous filler metal electrode and the work. Shielding is obtained from an external supplied gas source.
A small computer, usually fitting within a single cabinet, that has more memory and a higher execution speed than a microcomputer. It can be used by a several users at the same time.
In a recovery boiler, a tank that combines salt cake with black liquor to replenish chemicals.
Modulator/demodulator, a device used to transmit and receive digital data over normally analog communications lines, usually as an audio signal on telephone circuits. A modem attached to a computer performs a digital-to-analog conversion (modulation) of data and transmits them to another modem which performs a analog-to-digital conversion (demodulation) that permits its attached computer to use the data.
Devices for collecting and removing moisture precipitated from steam or compressed air.
The product of the force and the perpendicular distance from the line of action of the force to the centre of rotation of the body. The moment causes or tends to cause the body to turn or rotate about a point. A rotating pump shaft is an example of a body experiencing a moment. (Symbol mom.; unit Nm)
A weak base solution used in the removal of sour constituents from natural gas. Referred to as amine.
A series of heaters that are heated by steam to concentrate the weak black liquor into a more concentrated solution or strong black liquor of 50% concentration.
Boilers in which the flue gases make more than one pass over the heating surfaces.
Where no mechanical means is used to provide air for combustion. Airflow into the combustion chamber is the result of warm air being less dense than cool air.
A naturally occurring mineral (Fe3O4) that has magnetic properties such as the ability to attract other magnetic materials and is affected by the earth's magnetic field
Having a negative charge. Group V, VI, and VII elements on the periodic table form negative ions and tend to accept electrons.
The amount of pressure that is required on the suction side of the pump to prevent cavitation.
In computing, two or more computers connected for the purposed of exchanging messages and sharing data and system resources.
Addition of an acid or alkali (base) to a liquid to cause the ph of the liquid to move towards a neutral pH of 7.0.
A subatomic particle that has a mass almost equal to the proton but with no electronic charge, located in the nucleus of the atom.
A check valve that can be manually closed to prevent the back flow of steam from a header to a boiler.
Gas in a system that does not condense at the temperature and pressure at which it exists in the system.
In mechanics, perpendicular or at a right angle (90 degrees) to something. A normal stress is produced in a plane at 90 degrees to the force that is producing it.
The splitting of the atom or nucleus of the atom into subatomic particles resulting in the release of radiation and heat.
The number above the line in a common fraction; the numerator is divided by the denominator. If four is divided by seven (4/7), then 4 is the numerator.
A provincial government board that is responsible for the regulation of workplace safety standards.
In a bearing, a loose fitting ring that turns on a rotating shaft and hangs into an oil reservoir. As the ring turns it picks up oil and transfers it to the shaft and bearing.
An open vessel that accommodates the expansion and contraction of liquid in a hydronic heating system as it is heated or cooled.
Software designed to control the hardware of a specific data-processing system in order to allow users and application programs to employ it easily.
A device that protects a turbine from reaching a speed higher than it is intended for by shutting off the steam (steam turbine) or fuel (gas turbine) supply.
Oxidant. A product, material or substance is a controlled product within the meaning of Class C if it meets either of two conditions that causes or contributes to combustion.
Braided or woven material placed in single rings in a stuffing box and around the pump drive shaft. It controls leakage from the stuffing box.
A metal device placed around the drive shaft and at the rear of the stuffing box to hold the packing in place while providing enough pressure to control leakage.
The misalignment of the centre-lines of two shafts so that they are not parallel. They are offset either vertical or horizontally.
Plane figures that have four straight sides; the two opposite sides are parallel, i.e., square, rectangle, rhomboid, and rhombus.
The tiny particles of solids or liquid that are in a fluid stream that may cause respiratory problems in humans and atmospheric haze (smog).
A process that involves the controlled heating of the milk to eliminate all pathogenic microorganisms carried in the milk that may transmit diseases to humans.
A process that involves the controlled heating of the milk to eliminate all pathogenic microorganisms carried in the milk that may transmit diseases to humans.
An organization of all the elements arranged in periods and groups that show major properties and similarities.
A ferromagnetic material whose domains have been aligned so that their magnetic poles agree and add together.
The surfaces are shown in the same way as the eye would perceive them. Lines of an object are drawn in such a way that the parallel lines appear to converge towards one or more vanishing points.
The measure of acidity or alkalinity of a substance, indicated as a number, i.e.7 = neutral, above 7 = alkaline, below 7 = acidic.
A solution which changes colour from white to red in solutions with a pH of 8.3 or greater.
A measure of the hydroxide ions plus one half of the normal carbonate ions in aqueous suspension. Measured by the amount of sulphuric acid required to bring the water to a ph value or 8.3, as indicated by a change in colour of phenolphthalein.
A process in which organisms with the aid of chlorophyll (green plant enzyme), convert carbon dioxide and inorganic substances into oxygen and additional plant material, using sunlight for energy. All green plants grow by this process.
A change in matter where no new type of matter is produced, i.e.; the processes of boiling, melting and freezing.
Large diamond shaped safety marks used on the outsides of vehicles or large containers to indicate what type of dangerous goods are being transported in the units.
More than one phase or sine wave is generated. Some generators produce two, or more often, three phase power.
A compressor in which an increase in vapour pressure is attained by changing the internal volume of the compression chamber.
A pump in which pressure energy is added to a liquid by the action of the pump that causes a definite movement of the liquid into the discharge area.
Blowing through the boiler furnace after the combustion process has been shut down in order to remove combustibles.
In mechanics, energy of position. A body has potential energy because of its position relative to another location. For example, a rock on the edge of a cliff has potential energy relative to the ground at the cliff’s base.
The ratio of true power to apparent power. A power factor of 100% is the most efficient electrical power
A safety device that will open if the system pressure rises above the maximum safe pressure or if the water temperature reaches 99ºCelsius.
The ratio of the absolute discharge pressure to the absolute inlet pressure in any compression cycle.
A valve or rupture member designed to relieve excessive pressure automatically.
A valve held closed by a spring or other means and designed to automatically relieve excess pressure.
A pressure sensitive device that opens or closes an electrical circuit when the pressure reaches a set point, i.e. This switch may be used to start or stop a compressor when the system pressure reaches a low or high set point.
An unfired, closed vessel used for containing, storing, distributing, distilling, processing, or otherwise handling gas, vapour, or liquid exceeding the service and size limits as defined in CSA Standard B51.
That pressure at which vapour and liquid, or vapour and solid, can co-exist in stable equilibrium.
A pressure responsive mechanism designed to stop automatically the refrigeration system at a predetermined pressure at a specific location.
A boiler control device that affects the combustion process in the boiler according to the boiler steam pressure.
Maintenance that is carried out before a predicted malfunction or breakdown occurs.
A common fraction in which the numerator is a smaller number than the denominator, i.e. ½, 5/6.
A subatomic particle, located in the nucleus of atoms, having a positive electronic charge and a mass of 1.
A device used to measure humidity by comparing the wet and dry bulb temperatures of the air or space.
A graph that gives the properties of air at various conditions of temperature, enthalpy, and humidity.
In a Refrigeration system, the operation by which the refrigerant in a charged system is pumped into the liquid receiver.
In a boiler, the act of blowing air through the furnace to remove any unburned fuel. In refrigeration, the act of blowing out gas from a refrigerant-containing vessel, usually for the purpose of removing non-condensables.
A push nipple is a smooth piece of pipe, slightly tapered at both ends. Push nipples are used to connect radiator or cast iron boiler sections together, taking advantage of the nipple's taper to create a tight seal. Boilers and radiators whose sections are connected by push nipples make use of tie rods between the sections to hold them together.
Figures that have four sides, i.e., the square, rectangle, rhomboid, rhombus, trapezoid and trapezium.
Panels that are embedded in the surfaces of the walls, ceilings and floors of a space for the purpose of heating. They may be electrically or hydronically heated.
An arrangement of tubes that absorb radiant heat from the furnace flame and transfers it to saturated steam.
Energy transmitted by wave motion without the need of intervening matter, i.e. Light waves.
Random Access Memory, a type of computer memory that can be accessed for both reading and writing, as opposed to ROM (Read Only Memory).
The absolute temperature of the imperial system with graduations beginning at absolute zero. i.e. F + 460° = °R.
Whenever a force acts on a body there is an equal and opposite reaction to the force produced by the body. A reaction is a force (Newton’s) that is equal to, and acts in an opposite direction to, the force. Examples of reactions are the ground supporting you by pushing back up or a rifle hitting your shoulder when it is fired.
A type of turbine that uses the reaction principle to convert heat energy into mechanical energy.
A compressor in which each compressing element consists of a piston moving back and forth in a cylinder.
The return air passed through a conditioner before being returned to the conditioned space.
In a pulp mill, a boiler that burns black liquor to recover the pulping chemicals and produce steam in the process.
Temperature resistant material used in boiler furnaces for the purpose of protection around burners, lining fireboxes, sealing around openings, or making baffles.
A fluid that is used to absorb heat at low temperature and pressure, with a change of state, and reject heat at high temperature and pressure, with a change of state.
The process of reducing or maintaining the temperature of an area below that of the surrounding environment.
A process using interconnected components that form a closed circuit in which refrigerant is circulated for the purpose of absorbing and then releasing heat for the purpose of cooling.
A gas turbine cycle employing a heat exchanger before discharging the gases from the gas turbine to the atmosphere.
The heating of air to a desired temperature before admittance to the air-conditioned space.
A tube bank used to reheat the steam to its original temperature after expanding through the high-pressure turbine before it is fed into the intermediate stage of the turbine.
The ratio of the amount of water vapour in the air to the amount water vapour that the air can hold at that temperature.
A circuit device that uses a change in one electrical circuit to effect a change in another circuit by operating some control device such as a switch.
These are sources that can be renewed at a rate higher than it is being consumed.
The arrangement of direct current arc welding leads with the work as the negative pole and the electrode as the positive pole of the welding arc.
A parallelogram with four congruent sides, opposite sides parallel, and the angles that are not 90 degrees.
A parallelogram with four congruent sides of the same length and angles that are not 90 degrees.
In a gas processing plant, a solution of amine and sour/acid gas leaving the absorption tower.
Anti-friction bearings containing rollers that are either cylindrical or spherical in shape.
A type of positive displacement pump consisting of closely fitting elements rotating in a case. The rotation of these elements alternately draws in and discharges the liquid being pumped.
In rotary pumps these are usually called rotors, gears, screws or lobes, cam, wobble plate, sliding vanes. In centrifugal pumps they are known as impellers.
An automatic pressure-actuated relieving device suitable for use either as a safety valve or relief valve, depending on application.
An automatic pressure-relieving device actuated by the static pressure upstream of the valve and characterized by full-opening pop action due to the huddling chamber. It is used for gas or vapour service.
The difference in pressure between the popping pressure and the reseating pressure of a safety valve.
Prominent. Salient pole rotors have multiple pairs of poles in which the pole piece and windings are prominent and obvious.
The process of deposing of solid wastes in landfills by covering the waste with soil at the end of each day.
A pipe or conduit (sewer) intended to carry wastewater wastes from homes, businesses, and industries to the POTW (Publicly Owned Treatment Works). Storm water runoff or unpolluted water should be collected and transported in a separate system of pipes or conduits (storm sewers) to natural watercourses.
A system of horizontal and vertical piping that collects wastewater from floor drains, sinks, toilets and urinals. The sewage flows through the drainage piping to a central point of disposal.
The vapour at a certain temperature and pressure that will condense, if the pressure or temperature is lowered.
The pressure at which vapour and liquid can exist at equilibrium at a given temperature.
Water applied to the stuffing box in order to seal out air and to lubricate and flush the packing.
An end-suction centrifugal pump with the suction mounted above the eye of the impeller, a recirculation port between suction and discharge, or a flap gate on the suction connection.
A solid of crystal form that has conductivity between that of a conductor and an insulator.
Heat added to or removed from a substance that will result in a change in temperature. It is heat that is sensed by a thermometer.
A circuit in which the parts are arranged in sequence so that the current flows through each of them in turn.
A generator in which the field windings are connected in series with the armature windings so that the current induced in the armature also flows through the field windings
The condition (pressure, flow, temperature, etc.) that a control system is designed to maintain.
The brickwork surrounding the furnace in some older boiler designs. In modern boilers the setting includes the water walls, insulation, refractory and outer cladding that encloses the furnace.
A brass or stainless steel replaceable sleeve placed over the shaft where it passes through the stuffing box. Protects the shaft from wear by the packing.
An action that causes molecules of a body to be slid past each other. Scissors perform a shearing effect on paper. Shear force is used to punch out holes in a sheet of stainless steel. Shear stress is stress caused by a force that tends to cause particles to slide past each other.
A type of heat exchanger in which a nest or coil of tubes or pipes containing a fluid is inserted into a shell containing a second fluid. Heat is transferred from one fluid to the other through the tube or pipe walls.
A potentially life threatening condition that arises when there is an absence of adequate blood circulation throughout the body.
A circuit condition in which the current bypasses a section of the circuit and returns to the source.
A metal band that connects the outer ends of turbine blades to provide support and reduce vibration.
A dc generator in which the method of supplying excitation current to the field by connecting the field windings in parallel (shunt) with the generator’s output terminals.
A form of oxide of silicon that adsorbs moisture readily and is used as an air-drying agent.
A device that enables the advantageous application of forces. Industrial machines are combinations of basic machines. There are three basic types of basic machines: the lever, the inclined plane, and the hydraulic press. All simple machines: pulleys, wheel and axle, block and tackle, screw jack, gears, and cams, are variations of the three basic machines.
Sentences that contain one main, or independent, clause and contain no subordinate, or dependent clause.
A gas turbine arrangement in which the compressor and the gas turbine are coupled to one shaft.
Bearings composed of a sleeve, usually bronze, that are secured to one surface and are separated from a second surface by the lubricant.
A device used to determine relative humidity and having two thermometers mounted in parallel; one being bare and the other covered with fabric.
A ring of leather or rubber placed around the pump shaft in back of the stuffing box. Used to protect the bearings from water leakage out of the stuffing box.
Valve that requires a minimum of five full turns of its hand wheel to be fully open or closed.
The process of elimination or reduction of calcium and magnesium in water (hardness), i.e. ion exchange.
The programs, routines, and symbolic languages that control the functioning of the hardware and direct its operation.
A coil of wire wound on a cylinder whose length is greater than its diameter. When a current is passed through the wire an electromagnetic field is produced.
The density of a substance compared to the density of standard material, usually water.
A centrifugal pump designed so that the volute case is split horizontally. The case divides on a plane that cuts through the eye of the impeller.
In rigging, a bar or pipe that will distribute the weight evenly to ensure a load applied is lifted vertically.
A chimney that is the vertical passageway that expels flue gasses to the atmosphere well above the boiler.
A state where a body does not move or rotate. The algebraic sum of the parallel forces is equal to zero and the algebraic sum of moments is equal to zero.
A closed pressure vessel in which water is converted to steam by the application of heat.
The ratio of the amount of latent heat present in the steam compared to the amount of latent heat that it could contain at that pressure.
A transformer that causes a reduction in voltage value and increase in current value in the secondary circuit.
A transformer that causes an increase in voltage value and decrease in current value in the secondary circuit.
A separate pipe, conduit or open channel (sewer) that carries runoff from storms, surface drainage and street wash, but does not include domestic and industrial wastes.
A means for the collection and drainage of rainwater, snow melt that collects on roofs, parking lots, ramps and balconies, and sub-surface water.
The arrangement of direct current arc welding leads in which the work is the negative pole and the electrode as the negative pole of the welding arc.
The average of the various internal forces in a plane of area within a body as a result of the application of external forces.
Weak black liquor that has had its solids content increased to 60% by the removal of liquid through the application of heat.
That portion of the pump that houses the packing or mechanical seal. The stuffing box is usually referred to as the dry portion of the pump, and is located in back of the impeller and around the shaft.
An arc welding process that produces coalescence of metals by heating them with a bare metal electrode and the work. A blanket of granular, fusible, material shields the arc and the molten metal. Pressure is not used.
End-suction, close-coupled pumps that are designed so that the pump and motor may be submersed in water.
The tube or pipe that carries the refrigerant vapour from the evaporator to the compressor inlet.
A sewage tank installed below the level of the lowest floor, with a submersible-type centrifugal pump that is used to pump the sewage into the public sewer main.
A mainframe computer that is among the largest, fastest, or most powerful of those available at a given time.
Steam that has a higher temperature than the saturation temperature that corresponds to the pressure of the steam.
Used to remove impurities from the surface of the water in the top or steam drum.
A mixture of fine non-settling particles in a solution that may be removed by filtering.
A gas that does not contain any sour constituents, such as hydrogen sulphide; comprised usually of methane, CH4.
A switch is a device that is used to open a circuit or portion of a circuit and stop current flow.
The speed at which the electromagnetic field revolves around the stator of an induction motor.
Hanging "Do Not Operate" tags on and locking out equipment to ensure that is not operated while maintenance or inspection is carried out.
A fitting that indicates the temperature and pressure of the water leaving a hot water boiler.
A temporary magnet is one in which the domains do not remain aligned after the magnetizing force is removed.
Forces in tension, or tensile forces, are forces that are acting directly away from each other. They tend to pull the material apart.
A device, often equipped with a keyboard and a video display, through which data or information can enter or leave a computer system.
A temperature-sensing device that produces an electrical signal in proportion to the temperature change.
A device that controls the input of heat energy to maintain the pre-set temperature in the space being heated.
An expansion valve actuated by changes in superheat of the refrigerant vapour leaving the cooling unit.
Supports located in fire tube boilers to prevent bulging of front and rear tube sheets.
An arc welding process in which metals are fused by melting them with an arc between a single tungsten electrode and the work. Shielding is obtained from a gas mixture.
The process of adding a chemical to another solution drop by drop until an end point is reached.
When an energy system supplies all of the electrical and the heating requirements of a defined area.
Electronic device used as a voltage and current amplifier, consisting of semiconductor materials that share common physical boundaries. The materials most commonly used are silicon and germanium into which impurities have been introduced.
The process of detecting problems or potential problems through observation and testing.
Test valves on a water column used to verify the water level when the gauge glass is out of service.
A non-filler metal electrode used in arc welding or cutting, made mainly from the tungsten metal.
The measurement of the cloudiness of water due to the entrainment of suspended solids or other particles.
A machine that uses a medium such as water, steam, or gas to turn a wheel to produce mechanical energy.
A turning device that assures the turbine rotor is being rotated for the purpose of even cooling after a shutdown.
The ratio of the number of turns in the primary winding to the number of turns in the secondary winding.
Time Weighted Average (threshold limit value) - the refrigerant concentration in air for a normal 8 hour workday and a 40 hour work week to which workers may be repeatedly exposed, without health risk.
An engine requiring one revolution to complete one working cycle.
Electromagnetic radiation having wavelengths between that of violet light and x-rays.
A heater with electric resistance, steam, or hot water heating elements to heat the air. Natural or forced draft units are designed for wall mounting.
A device in a compressor for equalizing high and low side pressures when the compressor stops and for a brief period after it starts in order to decrease the starting load on the motor.
A system in which domestic water supply enters the building in the basement and travels through horizontal pipes.
An element of nature, symbol U, atomic number 92, used in the production of fuel rods for nuclear fission.
Low-pressure air compressors that take suction from a region below atmospheric pressure (turbine condenser) and discharge into the atmosphere.
An electron in the outer shell of an atom that takes part in forming chemical bonds or in the flow of electrical current.
A gas particularly one near to equilibrium with the liquid phase of the substance. In general, any gases below its critical temperature.
Any condition that may change continuously such as pressure, temperature, flow rate or level.
A quantity that has both magnitude and direction. The force of gravity is an example of a vector.
The ratio of the actual volume of gas moved by a compressor or pump to its displacement.
The spiral-shaped casing of a pump of increasing size that collects the liquid discharged by the impeller.
That form of movement of a mass of fluid having a whirling or circular motion that tends to form a cavity or vacuum at the center of a circle.
In a gas processing plant, a boiler used to combine preheated air and hydrogen sulphide gas to produce sulphur dioxide.
The recovery of heat from the exhaust system of boilers, gas turbines, and other similar devices.
A water column is a hollow forging or casting connected by pipes to the steam and water space of a boiler.
A condenser cooled by the increase of sensible heat of the water circulated through it.
The concussion that results when a moving volume of liquid in a pipe is suddenly stopped.
Boiler that has water in the tubes with heat and combustion gases around the tubes.
A furnace that is constructed with tubes throughout its enclosure and has water circulating through the tubes for cooling purposes.
A compartment or tank in which wastewater is collected. The suction pipe of a pump may be connected to the wet well or a submersible pump may be located in the wet well.
A lift station in which there is a single tank. Pumps can be installed in a wet well lift station in either a suction lift or suction head condition.
Equilibrium temperature of water evaporating into air when the sensible heat of the air supplies the latent heat of vaporization.
A chemical compound of sodium sulphide and sodium hydroxide, used for breaking down the lignin in wood.
The essential information that a person needs in order to handle a particular product safely.
A communication network that connects large numbers of nodes over long-distance communications links, i.e. common carrier telephone lines
Computer software either specially designed for or capable of word processing, including text formatting.
The substance which does the work in a heat engine; i.e., air is one of the working fluids used with gas turbines, refrigerant is the working fluid in refrigeration.
The aqueous extract made by slowly cooking the mash of malted grains and pure water during brewing.