All Terms Flashcards
1
Q
ABRASION
A
The wearing away of a surface by rubbing, as with sandpaper on wood.
2
Q
ABRASION RESISTANCE
A
The ability of a material to resist surface wear.
3
Q
ABRASIVE EROSION
A
Erosive wear caused by the relative motion of solid particles which are entrained in a fluid, moving nearly parallel to a solid surface.
4
Q
ABSOLUTE HUMIDITY
A
Amount of moisture in the air, indicated in kg/kg of dry air.
5
Q
ABSOLUTE PRESSURE
A
Total pressure measured from an absolute vacuum. It equals the sum of the gauge pressure and the atmospheric pressure corresponding to the barometer.
6
Q
ABSOLUTE PRESSURE
A
Air at standard conditions (70°F air at sea level with a barometric pressure of 29.92 in Hg) exerts a pressure of 14.696 psi. This is the pressure in a system when the pressure gauge reads zero. So the absolute pressure of a system is the gauge pressure in pounds per square inch added to the atmospheric pressure of 14.696 psi (use 14.7 psi in environmental system work) and the symbol is “psia”.
7
Q
ABSOLUTE TEMPERATURE SCALE
A
A scale of temperature measurement in which zero degrees is absolute zero.
8
Q
ABSOLUTE ZERO
A
A hypothetical temperature at which there is total absence of heat. Since heat is a result of energy caused by molecular motion, there is no motion of molecules with
9
Q
ABSOLUTE ZERO TEMPERATURE
A
Temperature measured from absolute zero (
10
Q
ABSORBENT
A
A material which, due to an affinity for certain substances, extracts one or more such substances from a liquid or gaseous medium with which it contacts and which changes physically or chemically, or both, during the process. Calcium chloride is an example of a solid absorbent, while solutions of lithium chloride, lithium bromide, and ethylene glycols are liquid absorbents.
11
Q
ABSORBER
A
That part of the low side of an absorption system, used for absorbing vapor refrigerant.
12
Q
ABSORPTION
A
A process whereby a material extracts one or more substances present in an atmosphere or mixture of gases or liquids accompanied by the material’s physical and/or chemical changes.
13
Q
ABSORPTION TOWER
A
A tower or column, which effects contact between a rising gas and a falling liquid, so that part of the gas may be taken up by the liquid.
14
Q
ACCELERATION
A
The rate of change of velocity, as a function of time. Expressed in m/s.
15
Q
ACCELERATION DUE TO GRAVITY
A
The rate of increase in velocity of a body falling freely in a vacuum. Its value varies with latitude and elevation. The International Standard is 9.81 m/s^2
16
Q
ACCEPTABLE WELD
A
A weld that meets all of the requirements and the acceptance criteria prescribed by the welding specifications.
17
Q
ACCESSIBLE HERMETIC
A
An assembly of motor and compressor, inside a single bolted housing unit.
18
Q
ACCUMULATOR
A
Storage tank which receives liquid refrigerant from evaporator and prevents it from flowing into suction line before vaporizing.
19
Q
ACETONE
A
A filler added to acetylene cylinders, capable of absorbing 25 times its own volume of acetylene.
20
Q
ACID
A
Literally hitter, but chemically the state of a water solution containing a high concentration of hydrogen ions.
21
Q
ACID ATTACK
A
Caused by an incomplete flushing after an acid cleaning process of boilers or similar equipment.
22
Q
ACID CLEANING
A
The process of cleaning the interior surfaces of steam generating units by filling the unit with dilute acid accompanied by an inhibitor to prevent corrosion and by
23
Q
ACID RAIN
A
Atmospheric precipitation with an pH below 5.6 to 5.7.
24
Q
ACID SOAK
A
A method of acid cleaning, in which the acid is pumped into the boiler and rests there for a period of time.
25
ACIDIC
The reaction of a substance with water resulting in an increase in concentration of hydrogen ions in solution (see acid).
26
ACIDIFIED
The addition of an acid (usually nitric or sulfuric) to a sample to lower the pH below 2.0. The purpose of the acidification is to "fix" a sample so it will not change until it is
27
ACIDITY
Represents the amount of free carbon dioxide, mineral acids, and salts (especially sulfates of iron and aluminum) which hydrolyze to give hydrogen ions in the water. The
28
ACOUSTIC
A term pertaining to sound, or the science of sound.
29
ACTIVATED CARBON
Is a specially processed carbon, used as a filter drier. Commonly used to clean air.
30
ACTIVATED SLUDGE
An aerobic biological process for conversion of soluble organic matter to solid biomass, removable by gravity or filtration.
31
ACTIVE STORAGE PILE
A method of stockpiling coal, sometimes called live storage. The pile is located outside the plant but adjacent to it, and usually contains four or five days of
32
ACTUATOR
The portion of a regulating valve, which converts mechanical, fluid, thermal, or electrical energy
33
ADIABATIC
Occurring with no addition or loss of heat from the system under consideration.
34
ADIABATIC CHANGE
A change in the volume, pressure, or temperature of a gas, occurring without a gain of heat or loss of heat.
35
ADIABATIC COMPRESSION
Compressing a gas without removing or adding heat.
36
ADIABATIC COOLING
A method in which paramagnetic salts are pre
37
ADIABATIC EFFICIENCY
The ratio of actual work output of a heat engine to the ideal output.
38
ADIABATIC EXPANSION
The expansion of a gas, vapor, or liquid stream from a higher pressure to a lower pressure, with no change in enthalpy.
39
ADJUSTABLE RESISTOR
A resistor whose value can be mechanically changed, usually by the use of a sliding contact.
40
ADSORBENT
A material which has the ability to cause molecules of gases, liquids or solids to adhere to its internal surfaces without changing the adsorbent physically or chemically.Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. This process differs from absorption, in which a fluid is dissolved by or permeates a liquid or solid.
41
ADSORPTION
A material which has the ability to cause molecules of gases, liquids or solids to adhere to its internal surfaces without changing the adsorbent physically or chemically.Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. This process differs from absorption, in which a fluid is dissolved by or permeates a liquid or solid.
42
ADVECTION
The transfer of heat by horizontal movement of air.
43
AERATION
Exposing to the action of air, like blowing air through water before discharging to a river.
44
AEROBIC
A condition in which "free" or dissolved oxygen is present in water.
45
AERODYNAMIC NOISE
Also called generated noise, self
46
generated noise
is noise of aerodynamic origin in a moving fluid arising from flow instabilities. In duct systems, aerodynamic
47
AGGLOMERATE
The clustering together of a few or many particles into a larger solid mass.
48
AGITATOR
A device used to cause motion in confined fluids.
49
AIR
A substance containing by volume approximately 79% nitrogen 20.95% oxygen, .94% argon, traces of carbon dioxide, helium, etc.
50
AIR CHANGES
A method of expressing the amount of air leakage into or out of a building or room in terms of the number of building volumes or room volumes exchanged.
51
AIR COIL
Coil on some types of heat pumps used either as an evaporator or a condenser.
52
AIR CONDITIONER
They are basically refrigeration devices cooling air and rooms rather then food compartments.
53
AIR CONDITIONER, UNITARY
An evaporator, compressor, and condenser combination
54
AIR CONDITIONING
The process of treating air to simultaneously control its temperature, humidity, cleanliness, and distribution to meet the requirements of the conditioned space.
55
AIR CONDITIONING UNIT
An assembly of equipment for the treatment of air so as to control, simultaneously, its temperature, humidity, cleanliness and distribution to meet the
56
AIR CONDITIONING, COMFORT
The process of treating air so as to control simultaneously its temperature, humidity, cleanliness and distribution to meet the comfort requirements
57
AIR COOLER
A factory
58
AIR DIFFUSER
A circular, square, or rectangular air distribution outlet, generally located in the ceiling and comprised of deflecting members discharging supply air in various directions
59
AIR DIFFUSION AERATORS
They are aerators into which air is pumped into the water through perforated pipes, plates, or any other method.
60
AIR DUCT
A tube or conduit for conveying air from one place to another.
61
AIR FLOTATION
A process of accelerating sedimentation, by introducing air into the water, this lowers the density of the water, and increases the differences in the densities of the
62
AIR GAP
The space between magnetic poles, or between the rotating and stationary assemblies in a motor or generator.
63
AIR HANDLER
The fan blower, heat transfer coil, filter, and housing parts, of a system.
64
AIR PURGE
The removal of undesired matter by replacement with air.
65
AIR SATURATED
Moist air in which the partial pressure of the water vapor is equal to the vapor pressure of water at the existing temperature. This occurs when dry air and saturated
66
AIR VENT
Valve, either manual or automatic, to remove air from the highest point of a coil or piping assembly.
67
AIR, AMBIENT
Generally the air surrounding the object.
68
AIR, DRY
Air without contained water vapor.
69
AIR, OUTDOOR
Air taken from outdoors and, therefore, not previously circulated through the system.
70
AIR, RECIRCULATED
Return air passed through the conditioner before being again supplied to the conditioned space.
71
AIR, REHEATING
In an air conditioning system, the final step in treatment, in the event the temperature is too low.
72
AIR, RETURN
Air returned from conditioned or refrigerated space.
73
AIRBORNE SOUND
Sound which reaches the point of interest by radiation through the air.
74
AIR
COOLED CONDENSER
75
ALCOHOL BRINE
A water and alcohol solution, which remains as a liquid below 0°C.
76
ALGAE
A minute fresh water plant growth which forms a scum on the surfaces of recirculated water apparatus, interfering with fluid flow and heat transfer. Lower form of plant life,
77
ALKALI
A substance having marked basic properties. Applying to hydroxides of potassium, sodium, lithium, and ammonium. They turn red litmus to blue. Includes hydroxides of the
78
ALKALINE
Having a pH greater than 7.
79
ALKALINITY
An expression of the total basic anions (hydroxyl groups) present in a solution. It also represents, particularly in water analysis, the bi
80
ALLEN TYPE SCREW
A screw with a recessed hex shaped head.
81
ALLOY
A substance having metal properties and being composed of two or more chemical elements of which at least one is a metal.
82
ALLOY STEEL
Steel containing specific quantities of alloying elements (other than carbon)and commonly accepted amounts of manganese, copper, silicon, sulfur, and phosphorus).
83
ALTERNATING CURRENT (AC)
Electric current in which the direction of the current alternates or reverses. In a 60 Hertz (cycle) current, the direction of current flow reverses in
84
ALTERNATOR
A device which converts mechanical energy, into alternating current.
85
ALTIMETER
An instrument used to measure the height above a reference point, such as ground or sea level.
86
ALUM
Is an aluminum sulfate or filter alum. Acts in the range of 5.0 to 8.0 pH.
87
ALUMINA
Aluminum oxide occasionally found as an impurity in water in very small amounts.
88
AMBIENT AIR TEMPERATURE
Temperature of fluid (usually air) which surrounds object on all sides.
89
AMBIENT CONDITIONS
The conditions of temperature, pressure, and humidity, existing around an instrument.
90
AMBIENT NOISE
The normal sound in a room or other location.
91
AMINE
A chemical use in water treatment as a filming or neutralizing agent to protect the metal parts.
92
AMMETER
An instrument for measuring the magnitude of electric current flow.
93
AMMETER SHUNT
A low
94
AMMONIA
Chemical combination of nitrogen and hydrogen (NH3). Ammonia is a very efficient refrigerant and identified as R
95
AMORPHOUS
A solid not having a repetitive three
96
AMPACITY
A wire's ability to carry current safely, without undue heating. The term formerly used to describe this characteristic was current capacity of the wire.
97
AMPERAGE
An electron or current flow of one coulomb per second, past a given point in a circuit.
98
AMPERE
The unit used for measuring the quantity of an electrical current flow. One ampere represent a flow of one coulomb per second.
99
AMPERE HOUR
A term used for rating battery capacity. As stated, an ampere for an hour
100
AMPERE TURNS
A term used to measure magnetic force. It represents the product of amperes, times the number of turns of the coil, in an electromagnet.
101
AMPLIFICATION
The process of obtaining an output signal greater than the input signal, through auxiliary power controlled by the input signal. The process of increasing the
102
AMPLITUDE
The maximum instantaneous value of alternating current or voltage. It can be in either a positive or negative direction. The greatest distance through which an oscillating
103
ANAEROBIC
A condition in which "free" or dissolved oxygen is not present in the water.
104
ANEMOMETER
An instrument for measuring the velocity of a fluid.
105
ANGLE VALVE
A type of globe valve design, having pipe openings at right angles to each other. Usually one opening on the horizontal plane and one on the vertical plane.
106
ANNEAL
To soften by heating and allowing to cool slowly.
107
ANNEALING
A process of heat treating metal, to get the desired properties of softness and ductility, (easy to form).
108
ANODE
In electrolysis or electrochemical corrosion, a site where metal goes into solution as a cation leaving behind an equivalent of electrons to be transferred to the opposite
109
ANODIZING
The treatment of a metal surface whereby the metal is made anodic.
110
ANSI
American National Standard Institute, which is an organization defining standards for computer language.
111
ANTI KNOCK VALUE
A premature explosive combustion, as the detonation of the fuel air mixture in an internal combustion engine, produces a characteristic knock. The Anti Knock
112
ANTICIPATING CONTROL
One which, by artificial means, is activated sooner than it would be without such means, to produce a smaller differential of the controlled property. Heat
113
ANTICIPATORS
A small heater element in two
114
ANTIFOAM AGENTS
The reduction of carry over by the addition of polymerized esters, alcohol’s, and amides. The antifoam agent is absorbed on the steam generating surface
115
ANTIFOULANTS
Are materials which prevent fouling from depositing on heat transfer equipment. Materials that prevent deposits forming
116
ANTIFREEZE
Compounds of glycol’s or alcohol’s, that lower the freezing point of cooling water systems.
117
ANTIOXIDANT
A substance which when added in small amounts to petroleum products, will delay or inhibit undesirable changes
118
APPARENT (EMF)
The apparent voltage, as measured by the drop in pressure due to a current flowing through a resistance.
119
APPARENT WATTS
The product of volts times amperes, in an alternating current circuit.
120
AQUEOUS
Watery. A substance containing water.
121
AQUIFER
A porous, subsurface geological structure carrying or holding water.
122
ARC
A flash, caused by an electric current ionizing a gas or vapor.
123
ARC BRAZING
A brazing process in which the heat required is obtained from an electric arc.
124
ARC FURNACE
An electric furnace, in which heat is produced by an arc between two electrodes.
125
ARC WELDING
A group of welding processes which produce coalescence of metals by heating them with an arc, with or without the application of pressure, and with or without the
126
ARC WELDING
A process where coalescence is obtained by heating with an electric arc.
127
ARMATURE
the rotating part of an electric motor or generator. The moving part of a relay or vibrator.
128
ARMATURE AIR GAP
The air space between the stationary and rotating parts of a motor or generator, through which magnetic lines of force pass.
129
ARMATURE BACK AMPERE TURNS
The magnetic field produced by current flowing in the armature winding, that opposes and reduces the number of magnetic lines of force,
130
ARMATURE BAR
Copper bars used in place of wire windings, in large armatures, generators, or motors.
131
ARMATURE CIRCUIT
The path that the current takes, in flowing through the windings from one brush to another.
132
ARMATURE COIL
The loop or coil of copper wire, placed on the armature core, and forming part of the winding.
133
ARMATURE CORE
The laminated iron part of the armature, formed from thin sheets or disks of steel, on which the windings are placed.
134
ARMATURE CURRENT
The current flowing from the armature of a generator, to the armature of a motor. Not including the current taken by the shunt field.
135
ARMATURE DEMAGNETIZATION
The reduction in the effective magnetic lines of force, produced by the armature current.
136
ARMATURE REACTION
The effect, that the magnetic field produced by the current flowing in the armature, has on the magnetic field produced by the field coils.
137
ARMATURE REGULATING RESISTORS
Are resistors, designed to regulate the speed or torque of a loaded motor, by placing a resistance in the armature or power circuit.
138
ARMATURE RESISTANCE
The resistance of the wire used in the windings of the armature, measured between the rings or brushes, or from positive to negative terminals.
139
ARMATURE SLOT
The groove or slot in the armature core, into which the coils or windings are placed.
140
ARMATURE TESTER
Any device used for locating faults or defects in the armature winding.
141
ARMATURE VARNISH
Is a liquid put on the field and armature windings, to improve the insulation of the cotton covering on the wires.
142
ARMATURE WINDING
All of the copper wire placed on the armature, and through which the current flows.
143
AROMATICS
A group of hydrocarbons of which benzene is the parent. They are called "aromatics" because many of their derivatives have sweet or aromatic odorous.
144
ARTIFICIAL MAGNET
Is a manufactured magnet, which is distinguished from a natural occurring magnet.
145
ASHRAE
The American Society of Heating, Refrigeration, and Air Conditioning Engineers.
146
ASME
American Society of Mechanical Engineers.
147
ASME APPENDIX SECTION I
Explains matter which is mandatory, unless specifically referred to in the rules of the code, including formulas.
148
ASME BOILER CODE
The boiler code listing standards, specified by the American Society of Mechanical Engineers, for the construction of boilers.
149
ASME PART PEB SECTION I
Requirements for electric boilers.
150
ASME PART PFH SECTION I
Requirements for feedwater heaters.
151
ASME PART PFT SECTION I
Requirements for firetube boilers.
152
ASME PART PG SECTION I
General requirements for all methods of construction.
153
ASME PART PMB SECTION I
Requirements for miniature boilers.
154
ASME PART PVG SECTION I
Requirements for organic fluid vaporizer generators.
155
ASME PART PW SECTION I
Requirements for boilers fabricated by welding.
156
ASME PART PWT SECTION I
Requirements for watertube boilers.
157
ASME SECTION I
Power Boilers.
158
ASME SECTION II
Material specifications.
159
ASME SECTION III
Nuclear Power Plant Components.
160
ASME SECTION IV
Heating boilers.ASME SECTION IX ASME SECTION V
161
ASME SECTION VI
Recommended rules for the care and operation of heating boilers.
162
ASME SECTION VII
Recommended rules for the care and operation of power boilers.
163
ASME SECTION VII APPENDIX
Consists of conversion factors for converting Imperial units to SI Units.
164
ASME SECTION VII SUBSECTION C1
Rules for routine operation of power boilers.
165
ASME SECTION VII SUBSECTION C2
Operating and maintaining boiler appliances.
166
ASME SECTION VII SUBSECTION C3
Rules for inspection.
167
ASME SECTION VII SUBSECTION C4
Prevention of direct causes of boiler failure.
168
ASME SECTION VII SUBSECTION C5
Is partial rules for the design of installations.
169
ASME SECTION VII SUBSECTION C6
Operation of boiler auxiliaries.
170
ASME SECTION VII SUBSECTION C7
Control of internal chemical conditions.
171
ASME SECTION VIII
Pressure vessels.
172
ASME SECTION XI
Rules for inservice inspection of Nuclear Power Plant components.
173
ASPIRATING PSYCHROMETER
A device which draws sample of air through it to measure humidity.
174
ASPIRATION
Production of movement in a fluid by suction created by fluid velocity.
175
ASTM
American Society for Testing and Materials.
176
ASYNCHRONOUS
Not having the same frequency. Out of step, or phase.
177
ASYNCHRONOUS GENERATOR
An induction generator.
178
ASYNCHRONOUS MOTOR
An induction motor, whose speed is not synchronous with the frequency of the supply line.
179
ATMOSPHERE
Is the mixture of gases and water vapor surrounding the earth.
180
ATMOSPHERIC PRESSURE
Pressure exerted by the weight of the atmosphere
181
ATOM
The smallest complete particle of an element, which can be obtained, yet which retains all physical and chemical properties of the element.
182
ATOMIC NUMBER
The number of protons found in the nucleus of an atom, of an element.
183
ATOMIC WEIGHT
The weight of an elementary atom, in relation to the weight of an atom of hydrogen. A hydrogen atom being taken as 1.00g.
184
ATOMIZE
Process of changing a liquid to minute particles or a fine spray.
185
ATTEMPERATING WATER IMPURITY
Refers to turbine deposits caused by impurities in the water used for attemperators. (Chemicals used with attemperating water should be of the
186
ATTEMPERATOR
An apparatus for reducing and controlling the temperature of a superheater vapor or a fluid.
187
ATTENUATION
The sound reduction process in which sound energy is absorbed or diminished in intensity as the result of energy conversion from sound to motion or heat.
188
ATTRITION
The rubbing of one particle against another in a resin bed
189
AUTOMATIC CONTROL
The process of using the differences, between the actual value, and desired value, of any variable, to take corrective action, without human intervention.
190
AUTOMATIC CONTROLLER
A device that measures the value of a measured variable, and operates to correct or limit the deviation from a selected reference. Both measuring and
191
AUTOMATIC DEFROST
System of removing ice and frost from evaporators automatically.
192
AUTOMATIC EXPANSION VALVE (AEV)
A type of metering device that senses low
193
AUTOMATIC EXTRACTION UNIT TURBINE
Bleeds off part of the main steam flow at one, two, or three points. Valved partitions between selected stages control the extracted steam
194
AUTOMATIC FROST CONTROL
Control which automatically cycles refrigerating system to remove frost formation on evaporator.
195
AUTOMATIC GOVERNING SYSTEM
A system which correlates steam flow, pressure, shaft speed, and shaft output, for any one turbine unit.
196
AUTOMATIC ICE CUBE MAKER
Refrigerating mechanism designed to automatically produce ice cubes in quantity.
197
AUTOMATIC RESET (INTEGRATION)
Is a type of control, in which the controller output, changes at a rate proportional to the deviation or error. The output will continue to change
198
AUTOTRANSFORMER
A transformer in which both primary and secondary coils, have turns in common. The step up or step down of voltage, is accomplished by taps in common
199
AUXILIARY CONTACTS
A set of contacts that perform a secondary function, usually in relation to the operation of a set of primary contacts.
200
AVAGADRO'S HYPOTHESIS
States that equal volumes of different gases, at the same temperature and pressure, will contain equal numbers of molecules.
201
AVAGADRO'S NUMBER (N)
The number of elementary units such as atoms, formula units, molecules, or ions, that constitute one mole of the said particle.
202
AVERAGING ELEMENT
A thermostat sensing element which will respond to the average duct temperature.
203
AXIAL FLOW COMPRESSOR
Uses rotor blades shaped like airfoils, to bite into the air, speed it up, and push it into the subsequent stationary blade passages. These passages are
204
AZEOTROPE
Having constant maximum and minimum boiling points.
205
BACK PRESSURE
Pressure in low side of refrigerating system
206
BACK SEATING
Fluid opening/closing such as a gauge opening or to seal the joint where the valve stem goes through the valve body.
207
BACK WORK RATIO
Is the fraction of the gas turbine work used to drive the compressor.
208
BACKGROUND NOISE
Sound other than the wanted signal. In room acoustics, the irreducible noise level measured in the absence of any building occupants.
209
BACKING RING
Backing in a form of a ring, generally used in welding of piping.
210
BACKWASH
The counter
211
BACTERIA
Microscopic unicellular living organisms.
212
BAFFLE
Plate or vane used to direct or control movement of fluid or air within confined area.
213
BAGHOUSE
A chamber containing bags for filtering solids out of gases.
214
BALLAST GAS
Are the nonflammable portion of the gas, such as carbon dioxide.
215
BAROMETER
Instrument for measuring atmospheric pressure. It may be calibrated in pounds per square inch, in inches of mercury in a column in millimeters or kPa.
216
BASE
An alkaline substance.
217
BASE METAL
The metal present in the largest proportion in an alloy. (Copper is the base metal in brass)
218
BASE METAL
The substrate metal that is coated or protected by a surface coating.
219
BASICITY
The ability of a substance to boost the pH after neutralizing all the acid species.
220
BATCH OPERATION
The utilization of ion
221
BAUDELOT COOLER
Heat exchanger in which water flows by gravity over the outside of the tubes or plates.
222
BEARING, AIR
A bearing using air as a lubricant.
223
BEARING, ALIGNING
A bearing with an external spherical seat surface that provides a compensation for shaft or housing deflection or misalignment.
224
BEARING, ANNULAR
Usually a rolling bearing of short cylindrical form supporting a shaft carrying a radial load.
225
BEARING, ANTI
FRICTION
226
BEARING, BABBIT
A bearing metal of non
227
ferrous material, containing several tin
based alloys, mainly copper, antimony, tin and lead.
228
BEARING, BALL
A rolling element bearing in which the rolling elements are spherical.
229
BEARING, BIG END
A bearing at the larger (crankshaft) end of a connecting rod in an engine.
230
BEARING, BIMETAL
A bearing consisting of two layers.
231
BEARING, BOTTOM END
(see bearing, big end)
232
BEARING, BUSH
A plain bearing in which the lining is closely fitted into the housing in the form of a bush, usually surfaced with a bearing alloy.
233
BEARING, CIRCULAR STEP
A flat circular hydrostatic bearing with a central circular recess.
234
BEARING, FIXED PAD
An axial or radial load bearing equipped with fixed pads, the surface of which a are contoured to promote hydrodynamic lubrication.
235
BEARING, FLOATING
A bearing designed or mounted to permit axial displacement between shaft and housing.
236
BEARING, FLOATING RING
A type of journal bearing that includes a thin ring between the journal and the bearing. The ring floats and rotates at a fraction of the journal rotational
237
BEARING, FLUID
(see hydrostatic bearing)
238
BEARING, FULL JOURNAL
A journal bearing that surrounds the journal by a full 360°.
239
BEARING, GAS
A journal or thrust bearing lubricated with gas.
240
BEARING, HALF JOURNAL
A bearing extending 180° around a journal.
241
BEARING, JOURNAL
A machine part in which a rotating shaft revolves or slides.
242
BEARING, MAGNETIC
A type of bearing in which the force that separates the relatively moving surfaces is produced be a magnetic field.
243
BEARING, MAIN
A bearing supporting the main power
244
BEARING, MITCHELL
(see tilting pad bearing).
245
BEARING, NEEDLE
A bearing in which the relatively moving parts are separated by long thin rollers that have a length
246
BEARING, NONCONTACT
A bearing in which no solid contact occurs between relatively moving surfaces.
247
BEARING, PEDESTAL
A bearing that is supported on a column or pedestal rather than on the main body of the machine.
248
BEARING, POROUS
Made from porous material, such as compressed metal powders, the pores acting either as reservoirs for holding or passages for supplied lubricant.
249
BEARING, ROLLER
A bearing in which the relatively moving parts are separated by rollers.
250
BEARING, RUBBING
A bearing in which the relatively moving parts slide without deliberate lubrication.
251
A roller
element bearing with one spherical raceway that automatically provides compensation for shaft or housing deflection or misalignment.
252
A bearing independent of external lubrication. These bearings may be sealed for life after packing with grease or may contain self
lubricating material.
253
BEARING, SLEEVE
A cylindrical plain bearing used to provide radial location for a shat, which moves axially. Sleeve bearings consist of one or more layers of bearing alloys, bonded to
254
BEARING, SLIDE
A bearing used or positioning a slide or for axial alignment of a long rotating shaft.
255
BEARING, STEP
A plane surface bearing that supports the lower end of a vertical shaft.
256
BEARING, THRUST
A bearing in which the load acts in the direction of the axis of rotation.
257
BEARING, TILTING PAD
A pad bearing in which the pads are free to take up a position at an angle to the opposing surface according to the hydrodynamic pressure distribution over
258
BEARING, TRUNNION
A bearing used as a pivot to swivel or turn an assembly.
259
BELLOWS
Corrugated cylindrical container which moves as pressures change, or provides a seal during movement of parts.
260
BELLOWS SEAL
A type of mechanical seal that utilizes a bellows for providing secondary sealing.
261
BIMETAL STRIP
Temperature regulating or indicating device which works on principle that two dissimilar metals with unequal expansion rates, welded together, will bend as
262
BIMETALLIC COUPLE
A joint or union of two dissimilar metals.
263
BIOCIDE
A chemical used to control the population of troublesome microbes.
264
BLACK LIQUOR
The liquid material remaining from pulpwood cooking in the soda or sulfate papermaking process.
265
BLAST FURNACE GAS
Is the waste product from furnaces used to smelt iron ores.
266
BLEEDER VALVE
A valve designed to slowly relief a liquid or gas form system.
267
BLEEDING
Slowly reducing the pressure of liquid or gas from a system or cylinder by slightly opening a valve.
268
BLEEDOFF
The continuous removal of water from a re
269
BLEEDOFF RATE
The rate at which water is continuously removed from a system.
270
BLOWDOWN
In connection with boilers or cooling towers, the process of discharging a significant portion of the aqueous solution in order to remove accumulated salts, deposits and
271
BOILER
Closed container in which a liquid may be heated and vaporized.
272
BOILER FEED WATER
The total water fed to a boiler producing steam. This water is the mixture of return steam condensate and makeup water.
273
BOILER HORSEPOWER
The work required to evaporate 34.5 lb of water per hour into steam from and at 100°C.
274
BOILER LAY
UP
275
BOILING
(See vaporization)
276
BOILING OUT
The boiling of high alkaline water in boiler pressure parts for the removal of oil, greases, prior to normal operation or after major repairs.
277
BOILING POINT
The temperature at which the vapor pressure of a liquid equals the absolute external pressure at the liquid
278
BOILING TEMPERATURE
Temperature at which a fluid changes from a liquid to a gas.
279
BORE
Inside diameter of a cylinder.
280
BOURDON TUBE
Thin
281
BOYLES' LAW
If the temperature on a gas is constant, the volume is inversely proportional to the pressure. By formula
282
BRANCH CIRCUIT
Wiring between the last overcurrent device and the branch circuit outlets.
283
BRASS
A copper
284
BRAYTON CYCLE (also referred to as the Joule Cycle)
A rotating machine in which compression and expansion take place. Gas turbine are such an example.
285
BRAZE
A weld produced by heating an assembly to suitable temperatures and by using a filler metal having a liquidus above 450°C. The filler metal is distributed between the closely
286
BRAZING, BLOCK
A brazing process in which the heat required is obtained from heated blocks applied to the parts to be joined.
287
BREAKTHROUGH
The first appearance in the solution flowing from an ion
288
BRINE
Water saturated with a chemical such as salt.
289
BRITISH THERMAL UNIT, (BTU)
The Btu is defined as the heat required to raise the temperature of a pound of water from 59° to 60°F.
290
BRITTLENESS
The tendency of a material to fracture without first undergoing significant plastic deformation.
291
BRONZE
A copper
292
BTU
British Thermal Unit.
293
BYPASS
A pipe or duct, usually controlled by valve or damper, for conveying a fluid around an element of a system.
294
BYPASS
Passage at one side of, or around, a regular passage.
295
BYPASS FEEDER
A closed tank that is installed in a system in "bypass," that is, in a side stream taken off the system and leading back to the system rather than directly in
296
BY
PASS GOVERNING
297
CALCAREOUS COATING OR DEPOSIT
A layer consisting of a mixture of calcium carbonate and magnesium hydroxide deposited on surfaces being cathodically protected against
298
CALCIUM
A scale forming element found in boiler feedwater.
299
CALCIUM CHLORIDE
A substance used to obtain calcium chloride brine.
300
CALCIUM SULFATE
Chemical compound (CaSO4) which is used at a drying agent or desiccant in liquid line dryers.
301
CALIBRATION
A process of dividing and numbering the scale of an instrument
302
CALORIE
It is equal to the amount of heat required to raise the temperature of one gram of water one degree Celsius.
303
CALORIMETER
Device used to measure quantities of heat or determine specific heats.
304
CANGE OF STATE
Change from one phase, such as solid, liquid or gas, to another.
305
CAPACITANCE
The property of an electric current that permits the storage of electrical energy in an electrostatic field and the release of that energy at a later time.
306
CAPACITOR, (CONDENSER)
A device that can store an electric charge when voltage is applied.
307
CAPACITY
The adsorption activity possessed in varying degrees by ion
308
exchange materials. This quality may be expressed as kilograins per cubic foot, gram
milliequivalents per gram,
309
pound
equivalents per pound, gram
310
CAPILLARY
The name given to the thin tube attached to the bulb which transmits the bulb pressure changes to the controller or indicator. The cross sectional area of the capillary is
311
CAPILLARY TUBE
The capillary tube is a metering device made from a thin tube approximately 0.5 to 6 metre long and from 0.025 to 0.090 inches in diameter which feeds liquid directly
312
CARBON DIOXIDE
Compound of carbon and oxygen (CO2) which is sometimes used as a refrigerant. Refrigerant number is R
313
CARBON FILTER
Air filter using activated carbon as air cleansing agent.
314
CARBON TETRACHLORIDE
Colorless nonflammable and very toxic liquid used as a solvent. It should never be allowed to touch skin and fumes must not be inhaled.
315
CARBONACEOUS EXCHANGER
Ion
316
CARBONATE
An ion or salt of carbonic acid, containing carbon and oxygen such as calcium carbonate. (CaC03)
317
CARBONATE HARDNESS
That hardness caused in water by bicarbonates and carbonates of calcium, and magnesium.
318
CARBONATE
POLYMER TREATMENT
319
A treatment method using synthetic polymers, generally used with high hardness (60
70) ppm and high alkalinity.
320
CARBOXYLIC
A term describing a specific acidic group (COOH) that contributes cation
321
CARRYOVER
The moisture and entrained solids forming the film of steam bubbles, as a result of foaming in a boiler. This condition is caused by a faulty boiler water condition. See
322
CASCADE
A series of stages in which the output of one stage is the input of the next stage.
323
CASCADE SYSTEMS
Arrangement in which two or more refrigerating systems are used in series
324
ultra
low temperatures.
325
CATHODE
In electrolysis or electrochemical corrosion, a site on a surface where actions in solution are neutralized by electrons to become elements that either plate out on the surface
326
CATHODIC PROTECTION
A method of preventing corrosion by making the metal a cathode in a conducting medium by means of a direct electrical current that is galvanic.
327
CATHODIC PROTECTION
Reduction of corrosion rate by shifting the corrosion potential of the electrode towards less oxidizing potential by applying an external electromotive force.
328
CATION
A positively charged ion that migrates through the electrolyte toward the cathode under the influence of a potential gradient.
329
CATION
EXCHANGE SOFTENERS
330
CATIONIC
The condition of a polymer, colloid, or large particle having exchangeable anions on its surface and an opposite, positive charge on the substrata.
331
CAUSTIC CRACKING
A form of stress
332
corrosion cracking most frequently encountered in carbon steels or iron
chromium
333
CAUSTIC EMBRITTLEMENT
An obsolete term replaced by caustic cracking.
334
CAUSTIC SODA
A common water treatment chemical, sodium hydroxide.
335
CAVITATION
The formation and collapse, within a liquid, of cavities or bubbles that contain vapor or gas or both. In general, cavitation originates from decreases in static pressure in
336
CAVITATION EROSION
Progressive loss of original material from a solid surface due to continuing exposure to cavitation.
337
CELSIUS TEMPERATURE SCALE
A thermometric scale in which the freezing point of water is called 0°C and its boiling point 100°C at normal atmospheric pressure.
338
CENTANE NUMBER
A measure of ignition quality of a fuel or petroleum with reference to normal centane high
339
CENTRIFUGAL COMPRESSOR
Pump which compresses gaseous fluids by centrifugal force.
340
CENTRIFUGAL FORCE
On a centrifugal pump, it is that force which throws water from a spinning impeller.
341
CENTRIFUGAL PUMP
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
342
CENTRIFUGAL PUMP
Pump which produces fluid velocity and converts it to pressure head.
343
CHANGE OF STATE
Condition in which a substance changes from a solid to a liquid or a liquid to a gas caused by the addition of heat. Or the reverse, in which a substance changes
344
CHANNELING
Cleavage and furrowing of the bed due to faulty operational procedure, in which the solution being treated follows the path of least resistance, runs through these
345
CHARGE
Amount of refrigerant placed in a refrigerating unit.
346
CHARGING BOARD
Specially designed panel or cabinet fitted with gauges, valves and refrigerant cylinders used for charging refrigerant and oil into refrigerating mechanisms.
347
CHECK VALVE
Device which permits fluid flow in one direction.
348
CHELATE
Is a molecule, similar to an ion exchanger, capable to withdraw ions from their water solutions into soluble complexes.
349
CHEMICAL CLEANING
Using a solvent solution to remove mill scale and corrosion products.
350
CHEMICAL FEEDLINE
The line which feeds the boiler treatment chemicals into the boiler.
351
CHEMICAL PRECIPITATION
When the chemicals react with the dissolved minerals in the water to produce a relative insoluble reaction product. A typical example of this takes place
352
with the lime
soda softening process.
353
CHEMICAL REFRIGERATION
System of cooling using a disposable refrigerant. Also called an expendable refrigerant system.
354
CHEMICAL STABILITY
Resistance to chemical change which ion
355
CHILL FACTOR
Calculated number based on temperature and wind velocity.
356
CHILLED
WATER SYSTEM
357
A re
circulating water system using water chilled in a refrigeration machine as a source for cooling.
358
CHILLER/HEATERS
A unit that supplies either chilled water for cooling or hot water for heating, (HVAC).
359
CHLORIDE
An ion, compound, or salt of chlorine, such as sodium chloride (NaCl) or calcium chloride (CaCl2).
360
CHLORINATION
A process in which chlorine gas or other chlorine compounds are added to the water for the purpose of disinfecting.
361
CHOKE TUBE
Throttling device used to maintain correct pressure difference between high
362
side and low
side in refrigerating mechanism. Capillary tubes are sometimes called choke
363
CHORDAL THERMOCOUPLE
A thermocouple installed in furnace tubes, designed to measure the effectiveness of water treatment within the boiler.
364
CIRCUIT
An electrical arrangement requiring a source of voltage, a closed loop of wiring, an electric load and some means for opening and closing it.
365
CIRCUIT BREAKER
A switch
366
CLAY
Finely suspended earth mineral sometimes found as an impurity in water.
367
CLEARANCE SPACE
Space between top of piston and the valve plate.
368
CLEARANCE VAPOR
The vapor remaining in the clearance space at the end of each discharge stroke.
369
CLOSED CYCLE
is the gas turbine arrangement, in which the exhaust is directed back again to compressor without coming in contact with the atmospheric air.
370
CLOSED FEEDWATER HEATER
An indirect
371
CLOSED RE
CIRCULATING WATER SYSTEM
372
A system using as a heat
transfer medium water that continuously circulates through closed piping and heat exchanger without
373
COCOAGULANT
A substance that promotes the clumping of particulate matter in water, forming a larger mass and thus promoting settling of particulates and clarification of the water.
374
COAGULATION
Is the process whereby finely divided particles of turbidity and color, capable of remaining in suspension indefinitely, are combined by chemical means into masses
375
COALESCENCE
The gathering together of coagulated colloidal liquids into a single continuous phase.
376
CODE INSTALLATION
Refrigeration or air conditioning installation which conforms to the local code and/or the national code for safe and efficient installations.
377
CO
EFFICIENT OF CONDUCTIVITY
378
COEFFICIENT OF EXPANSION
A measure of the change in length or volume of an oject, specifically, a change measured by the increase in length or volume of an object per unit
379
COEFFICIENT OF FRICTION
The dimensionless ratio of the friction force (F) between two bodies to the normal force (N) pressing these bodies together
380
COEFFICIENT OF PERFORMANCE (COP)
Ratio of work performed or accomplished as compared to the energy used under designated operating conditions.
381
COGENERATION
A term used to describe the combination of different thermodynamic cycles for the purpose of increasing all
382
CO
GENERATION GENERATION
383
a term applied to identify the generation of people interested in co
generation.
384
COLD
The absence of heat
385
COLD DECK
The cooling section of a mixed air zoning system.
386
COLD JUNCTION
That part of a thermoelectric system which absorbs heat as the system operates.
387
COLD PROCESS
A water treatment process carried out at room temperature.
388
COLD WALL
Refrigerator construction which has the inner lining of refrigerator serving as the cooling surface.
389
COLLOIDAL
A state of suspension in a liquid medium in which extremely small particles are suspended and dispersed but not dissolved.
390
COLLOIDS
Organic matter of very fine particle size, usually in the range of 10
391
5 to 10
7 cm in diameter. It tends to inhibit the formation of dense scale and results in the deposition of
392
COLUMN OPERATION
Conventional utilization of ion
393
COMBINED FEEDER CUTOFF
A device that regulates makeup water to a boiler in combination with a low
394
COMBINED STEAM
GAS PLANT
395
COMBINED TREATMENT
A method of physical treatment , followed by the addition of chemicals to remove oxygen.
396
COMBUSTION
The act or process of burning.
397
COMFORT CHART
A chart showing effective temperatures with dry
398
COMFORT COOLER
System used to reduce the temperature in the living space in homes. These systems are not complete air conditioners as they do not provide complete control of
399
COMFORT COOLING
Refrigeration for comfort as opposed to refrigeration for storage or manufacture.
400
COMFORT ZONE
(Average) the range of effective temperatures over which the majority (50 percent or more) of adults feels comfortable
401
COMMON NEUTRAL
A neutral conductor that is common to, or serves, more than one circuit.
402
COMPOSITION
The elements or chemical components that make up a material and their relative proportions.
403
COMPOUND
They are chemically combined elements with definite proportions of the component elements.
404
COMPOUND GAUGE
Instrument for measuring pressures both above and below atmospheric pressure.
405
COMPOUND REFRIGERATING SYSTEMS
System which has several compressors or compressor cylinders in series. The system is used to pump low pressure vapors to condensing
406
COMPRESSION
Term used to denote increase of pressure on a fluid by using mechanical energy.
407
COMPRESSION RATIO
Ratio of the volume of the clearance space to the total volume of the cylinder. In refrigeration it is also used as the ratio of the absolute low
408
the absolute high
side pressure.
409
COMPRESSION, ADIABATIC
Is compressing a gas without removing or adding heat.
410
COMPRESSOR
Pump of a refrigerating mechanism which draws a low pressure on cooling side of refrigerant cycle and squeezes or compresses the gas into the high
411
COMPRESSOR
The pump which provides the pressure differential to cause fluid to flow and in the pumping process increases pressure of the refrigerant to the high side condition.
412
COMPRESSOR DISPLACEMENT
Volume, in cubic inches, represented by the area of the compressor piston head or heads multiplied by the length of the stroke.
413
COMPRESSOR SEAL
Leak proof seal between crankshaft and compressor body in open type compressors.
414
COMPRESSOR SURGING
An instability of air flow with axial compressor on the first stages of these compressors. Air flow might even be reversed that point.
415
COMPRESSOR TURBINE
in terms of a gas turbine arrangement, it is the turbine which drives the compressor only.
416
COMPRESSOR, CLEARANCE POCKET
Small space in a cylinder from which compressed gas is not completely expelled. This space is called the compressor clearance space or
417
COMPRESSOR, ROTARY BLADE
Mechanism for pumping fluid by revolving blades inside cylindrical housing.
418
COMPRESSOR, SINGLE
STAGE
419
Compressor having only one compressive step between low
side pressure and high
420
COMRESSIBILITY
The ease which a fluid may be reduced in volume by the application of pressure, depends upon the state of the fluid as well as the type of fluid itself.
