WATER COOLED COMPRESSOR – A compressor whose cylinder is water jacketed and through which flows a current of cold water which functions as a transmission medium to carry off some of the heat of compression.
WORK – The overcoming of resistance through a certain distance by the expenditure of energy.
WADDLE – A sideways vehicle shake due to a faulty radial tyre. Most noticeable when a vehicle moves slowly.
WANDER – A condition in which the vehicle does not follow a straight path and randomly drifts in one direction or the other.
WEIGHT TRANSFER – The changes in radial loads on the front and rear wheel tyres due to the centre of gravity location ring braking.
WHEELS – The wheels (wheel and tyre assembly) support the weight of the vehicle. The assembly provides ride quality, load carrying capacity, and vehicle handling characteristics.
WHEEL ALIGNMENT – The position of the front wheels in relation to the suspension and steering geometry.
WHEEL BALANCER – A device that checks a wheel, either statically or dynamically, for balance.
WHEEL BASE – Distance between center of the front wheel and center of rear wheels.
WHEEL CYLINDER – In the hydraulic braking system, hydraulic cylinders placed in the brake mechanisms at the wheels; hydraulic pressure from the master cylinder causes the wheel cylinders pistons to move the brake shoes.
WHEEL FIGHT – The tendency of a steering system to be easily deflected by uneven road surfaces. Causes changes in toe that result in tyre wear.
WHEEL OFFSET – The distance between wheel attachment flange and the wheel rim centre plane.
WHEEL PACK BEARING – A pre-assembled self-lubricated bearing assembly used on the drive wheels with independent suspension.
WHEEL SIDEWAYS DISPLACEMENT – Sideways movement of the wheel as the suspension goes from jounce to rebound.
WHEEL SIZES – are indicated by three measurements, namely rim diameter, rim width and flange height.
WHEELSLlP – Sideways movement of the tyre tread across the foot print.
WHEEL RUNOUT – The amount the wheel wobbles as it rotates.
WHEEL TRAMP – Tendency of the wheel to move up and down so it repeatedly bears hard or tramps, on the pavement. Sometimes called high speed shimmy.
WIND SHIELD WIPER – A mechanism which utilizes a rubber blade to wipe the wind shield, it is either vacuum or electrically operated.
WASH – Casting defect resulting from erosion of sand. Also refers coating materials applied to moulds, cores etc.
WASTER – Faulty casing.
WHIRL GATE – Gating system in which the metal enters a circular reservoir at a tangent and so whirls around, leaving dirt and slag behind before passing into the mould cavity.
WHISTLERS – Small openings from isolated mould cavities to allow gases to escape easily.
WHITE IRON – An extremely hard cast iron that results from pouring the hot metal into a mould with a chill plate in it.
WROUGHT IRON – Contains 1-2% slag, which is distributed through the iron as threads and fibres imparting a tough fibrous structure. Usually contains less than 0.1 % carbon. It is tough, malleable, and relatively soft.
WROUGHT METALS – These are metals furnished in the shapes resulting from the operations such as rolling, forging, drawing and extrusion.
WARNING LIGHT – A light on the instrument or control panel that turns on to warn of low oil pressure.
WORK OF FRICTION – Product of the frictional force and the distance through which it moves.
WIND BOX – A plenum from which air is supplied to a stoker or to gas or oil burners.
WINDAGE LOSSES – When moving blades come in contact with inactive fluid, some kind of kinetic energy is imparted to the fluid at the expense of the kinetic energy of the blades. There is also frictional effect. This loss is known as windage losses.
WORK RATIO – The ratio of the actual work output (in heat units) to the isentropic heat drop from the total head inlet to the static outlet conditions.
WORK HARDENING – Phenomena in which the grains become distorted and elongated in the direction of working (rolling). This process, also called STRAIN HARDENING, hardens and strengthens metals but reduces their ductility.
WANKEL ENGINE – A rotary type engine, in which a three lobe rotor turns eccentrically in a specially shaped housing.
WET LINER – When fitted in the cylinder block has water on the external surface of the liner. Good cooling is realized by having the water in direct contact with the liner.
WRIST PIN – A cylindrical (solid or hollow) pin that attaches the piston to the connecting rod.
WATER GAUGE – A gauge that shows the proper water level which must be maintained in a boiler to avoid overheating damage.
WIRE GAUGE – Sizes of standard wire and sheet metal are normally expressed not by a dimension in cm, but by a number or gauge size.
WHITWORTH GAUGE – Type of plug, and caliper gauge introduced by Joseph Whitworth.
WICKMAN GAUGE – Special form of adjustable snap or horse shoe type of gap gauge.
WAYS – The flat or V shaped bearing surfaces on machine tools over which other movable parts slide.
WOODRUFF KEY – A flat semicircular piece of metal used as a key in a special circular key seat slot cut in a shaft to drive a gear, pulley or other part.
WANKEL ENGINE – A rotary type engine in which a three lobe rotor turns eccentrically in an oval chamber and thus performs cycle of operations.
WATER BRAKE – A device for engine testing in which the power is dissipated by churning water.
WELDING MACHINE – Equipment used to perform the welding (joining) operation, for example, spot welding machine, arc welding machine, seam welding machine etc.
WORM – A threaded cylinder which meshes with and drives a worm gear, the thread being specially designed to mate with the teeth in the worm gear.
WORM GEARS – Gears with teeth cut at an angle to be driven by a worm.
WEIGHT OF A BODY – Force which the body exerts on the support due to the force of gravity.
WINCH – Equipment used for hauling, pulling, or hoisting e.g., rope and chain winches, stationary winches, mobile winches.
WEAR – A surface deterioration of contacting surfaces that destroys their operating relationship, or causes rupture if carried far enough.
WELDMENT – A unit formed by welding together an assembly of pieces.
WORKING STRESS – The actual stress that the part will be designed to handle.
WELDING – Joining of metals by the application of heat, without the use of solder or any other metal or alloy having a lower melting point than the metals being joined.
WHEEL TRUING – Cutting off irregularities on a rotating grinding wheel with a diamond dresser.
WORM GRINDING – Grinding the threads of worm gear wheels as a means of finishing them after the hardening operation.
WIRE DRAWING – Reduction in diameter of metal rods by drawing them through conical openings in the blocks.
WORM GEARING – A form of special gearing in which the axes of the driving and driven shafts are usually at right angles and the velocity ratio is high, the driving gear being of smaller diameter.
WORK – Product of the force acting on a body and the displacement of the body caused by that force.
WORKING SURFACE – With respect to a gear, the working surface above the pitch surface is called the FACE OF THE TOOTH and that below the pitch surface is called the FLANK OF THE TOOTH.
WATER CONTROL VALVE – Used in A/C systems to regulate the flow of coolant to the heater core.
WATER ICE REFRIGERATION SYSTEM – Heat is absorbed as ice melts, producing the desired cooling effect.
WET BULB TEMPERATURE – The temperature read, by a wet bulb thermometer, this is an ordinary thermometer the bulb of which is wetted by being surrounded by a sheath of muslin kept wet by pure water.
WEDGE COMBUSTION CHAMBER – A combustion chamber resembling in shape, a wedge.
WASTE HEAT BOILER – A boiler which uses byproduct heat such as from a blast furnace in a steel mill, exhaust from a gas turbine, or by products from a manufacturing process. Waste heat is passed over the heat exchanger surfaces to produce steam or hot water for conventional use.
WATER ANALYSIS – Analyzing a water sample i.e., process of finding out how much of the various impurities and other chemical substances are present in the water. The results are usually expressed in parts per million (ppm).
WATER COLUMN – A boiler fixture consisting of a cylindrical piece to which are attached the water gauge and gauge cocks, thus combining the two into one unit. The top and bottom have outlets which connect it with the boiler below and above the water level.
WATER GAUGE – A device used to indicate the height of water within a boiler.
WATER GRATE – A series of pipes connected close together in parallel to a header at one end and to upflow elements at the other.
WATER LINE – The level at which water stands in the boiler.
WATER TUBE – One which is surrounded by the products of combustion, the water being inside the tube.
WATER TUBE BOILER – A boiler which contains one or more relatively small drums with a multiplicity of tubes in which water steam circulate and hot gases surround the tubes.
WINDOW PATCH – A patch used to seal a hole cut in a water tube to provide access for welding the backside of a circumferential joint, or to replace a small, sharp bag.
WILLANS LINE – The line which represents the total weight of steam necessary per hour plotted as ordinates against the corresponding engine loads (either as IHP, BHP or KW) as abscissa.
WIRE DRAWING – In a steam engine, the fall in pressure caused by steam flowing through the restricted (valve) Passage immediately before the point of cut off.
WORKING STEAM – The steam that actually flows through the blades, this is different from the total steam flow through the turbine.
WEIGHT – It refers to the force exerted by gravity on the given mass. Weight is proportional to mass, but the proportionality factor is different at different locations.
WET STEAM – Steam containing intermingled moisture, mist or spray.
WORK – The overcoming of resistance through a certain distance by the expenditure of energy.
WORKING AGENT – Substance in a heat engine which alternately takes in and rejects heat, expanding and contracting when doing so, and overcoming the resistance opposing these changes.
WET CLUTCH – A multiple plate clutch which runs in an oil bath (primary drive).
WHEEL BALANCING – An equal distribution of weight achieved by determining where the wheel is heavier and then placing weights opposite the heavy portion.
WHEEL BASE – Distance between the center of front wheel and the center of rear wheel.
WHEEL WEIGHT – Small weights attached to the wheel to balance the wheel and the tyre assembly.
WIDE RATIO GEARBOX – A gearbox having wide ratio spacing between gears. A wide ratio gear box is used in off road and trials motor cycles.
WEAVE BEAD – A type of weld bead made with transverse oscillation.
WELD – A localized coalescence of metals or non-metals produced either by heating the materials to the welding temperature, with or without the application of pressure or by the application of pressure alone and with or without the use of filler material.
WELDING ELECTRODE – A component of the welding circuit through which current is conducted and which terminates at the arc, molten conductive slag or base metal.