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FULLER — Tool used by the smith for making rivetted joints or shaped work on the anvil, or working under the power hammer. The elements that make up the wheel are 1 abrasive, 2 grain size, 3 bond, 4 grade and 5 structure. There are nine standard shapes and many sizes and grades for grinding practically all kinds of materials.
HAMMER sledge — Tool with a steel head and a wooden handle, a larger type of hammer which may have the head weighing from, say 2 to 7 kg with the handle varying from, say 60 to 90cm in length. These are used only for small threads on brass, or for rounding off the tops and bottoms of threads previously formed by the vee tool in the screw cutting lathe.
HAND FILE — Commonly used file parallel in width from the tang to the tip, but slightly thinned off in thickness for about one third of its length towards the point. It has a thread cut on it, and is fluted to provide cutting edges. A square at the shank end makes it possible to attach a wrench for turning by hand. HAND TOOL — A general term that applies to wide variety of small tools used by hand instead of being power driven, as layout tools, wrenches and hammers. HOB — Fluted rotary cutter used to produce spur, helical, and worm gears, a worm shaped cutting tool having a number of flutes or gashes running across the threads so that a series of cutting edges is formed.
Mating sections are similar to half side cutters or staggered tooth side cutters with uniform or alternate helical teeth so designed that the paths of teeth overlap when in proper assembly. LAP — A tool for finishing internal and external surfaces of the workpiece by charging the lap with a fine abrasive. Always made from metals which are softer than the metal being lapped. For milling cutters, when viewed from the spindle or shank end, the cutter would turn counter- clockwise.
PIN PUNCH — Type of punch, sometimes called a drive pin punch, employed in removing dowel pins, cotter pins, rivets and similar light objects used as temporary fastenings, also for punching small holes in sheet metal. REAMER — Multiedged cutting tool having cutting edges arranged down the length of the tool, the teeth and the flutes being either straight and parallel to the axis or alternatively helical with a lead opposite to the direction of rotation.
RIFFLER — File with a curved working surface specially made for filing concave surfaces, such as the insides of oddly shaped holes in castings. A cutter that rotates clockwise when viewed from the spindle end is said to have right hand rotation. A cutter has a right hand helix when the flutes slant downward to the right when viewed from the front or twist clockwise when viewed from the end. With no side rake it may be used to cut either right or left hand.
SCRAPER — Tool used to reduce the high spots on a surface which has previously been smoothed as far as possible by machining or filing. Scraping is hand operation. SCRIBER — Metal tool, shaped something like a thin pencil, having a sharply pointed end for marking lines on metal surfaces so as to locate the positions of holes, angles, machining boundaries. SCRIBING BLOCK — Tool comprising a heavy base, a rigid vertical spindle and a sleeve device capable of travelling up and down the spindle and holding a scriber, used primarily on surface plates for the purpose of scribing lines parallel to a level surface or to another line.
Also, any deformation of metal or other material stressed beyond its elastic limit. SHANK — The non-cutting end of a tool which fits into the holding device for driving, as the taper shank on a drill. The body of the cutter is slightly less in length than its diameter, and is made with a hole through the centre to fit a standard arbor.
The term shell is used to differentiate this type of reamer from the solid reamer. It is more of a milling cutter than a drill. SQUARE — The name of tools of various designs and types used for laying out, inspecting, and testing the squareness of workpieces. Also, lines or surfaces which meet at right angles. Used for chamfering or for rough cuts on flat surfaces where sharp corners are necessary.
Also, used for finishing cuts on cast iron. The stock is the name given to the portion of the tool hand holder into which the dies are placed and which enables the dies to be rotated without undue effort.
The assembled unit is called die and stock. TANG — Two opposite flats milled at the end of taper shanks which enter a slot in the spindle to prevent slipping and provide a means of removing the shank from the spindle. Also the name of the part of a file that fits into the handle. TAP — A hardened and tempered steel tool for cutting internal threads which has flutes lengthwise to provide cutting edges for the threads and a square at the end of the shank for turning the tap with a wrench.
TAP DRILL — A twist drill, the size of which will produce a hole that can be tapped with a specified tap to give a thread of required depth or percentage of full depth. Prongs extend down into the flutes of the broken portion. By attaching a wrench to the extractor, the broken part in the hole may be loosened and backed out.
It is chamfered at its small end for a distance equal to 4 or 5 times the distance between threads. This device is rotated in a drilling machine to cut out large circles or holes from solid metal by cutting a narrow groove around the metal.
These flutes leading from the cutting faces, called lips, provide an exit for the metal that is removed when the hole is being drilled. Used for the fast removal of metal when slots or keyways are to be cut on the milling machine.
WHEEL grinding — Power driven wheel consisting of abrasive particles, held together by artificial or natural, mineral, metal or organic bonds. It is also used for setting the tool square with the axis of the workpiece.
With this, it is possible to determine exactly the depth of cut taken. CALIPER — Instrument used for measuring distances between or over surfaces, or for comparing dimensions of workpiece with such standards as plug gauges, graduated rules etc.
They are used for dividing distances into a number of equal parts. Also used for transferring dimensions from a rule to the work. Also it may be called a drill point gauge or a drill angle gauge. They are used for checking clearances. GAUGE — A tool or instrument for checking or measuring the sizes of metal parts to determine whether the dimensions are within the specified limits.
INDICATOR — A sensitive instrument which shows slight variations when testing the trueness, or alignment of a workpiece, fixture or machine part such as a milling vice. Dial indicators may be graduated to read small linear variations.
Vernier protractor is used for measuring angles accurately. These are useful for measuring in restricted places or on curved surfaces. LEVEL, SPIRIT — Instrument consisting essentially of a small sealed glass tube containing spirit alcohol or ether so mounted that the enclosed bubble of air occupies a central position only when the instrument is placed horizontally.
ODD LEG — Caliper having one leg bent inwards at its ends, like the two legs on a pair of inside calipers, the other leg being pointed or having a separate hardened point attached to it. May be straight or tapered, plain or threaded, and of any cross-sectional shape. A ring gauge may be cylindrical or conical, plain or threaded.
It is used to find the pitch and number of threads per inch on a screw, tap or die. TEMPLATE — A flat pattern or guide plate usually made from sheet metal and used as a gauge or guide when laying out, drilling, forming in a machine or filing irregular shapes on metal workpieces.
TRAMMELS — are generally used for laying off and checking dimensions of several feet, they are generally used in conjunction with a large steel rule, which may be from 3 to 10 ft long. One leg can be separated or opened to remove the caliper and then returned to the measured size. TRY SQUARE — Instrument used for setting and checking a line, an edge or a face which is required to be at right angles to some other plane which should be regarded as a datum or reference plane.
VERNIER — Small-scale, for making accurate measurement, carrying a certain number of graduations equalling in their combined length a different number of graduations, usually one more or one less, on the main scale of the instrument to which the vernier is attached. AIR GATE — A vertical channel for the removal of gases from the mould; checking of the filling of the mould cavity with metal and feeding up the casting with metal during solidification. It may be covered with a cope, or cast open, according to the type of work.
May be cereal, oil, clay, resin, pitch etc. BLEED — Molten metal oozing out of a casting stripped or removed from the mould before solidification. Casting BOSSES — Bosses are often located on a wall of a casting and should be so designed that a heavy section of metal leads to the riser. BOT — Clay wedge used in a cupola to stop the hole through which the metal is run.
BURN OUT — Usually refers to the removal of the disposable wax or plastic pattern in the investment moulding process by heating the mould gradually to a sufficiently high temperature to consume any carbonaceous residues.
Act of pouring molten metal into a mould. Molten metal is moved from the center to the periphery by centrifugal action. The mould can be made in a flask or in the form of a shell. CEREAL — Substance derived from corn flour, which is added to core and moulding sands to improve their properties for casting production. After a short time, the penetrant seeps out of the cracks into the whiting, causing an appreciable difference in whiteness.
CHILL — A metal object placed on the outside or inside a mould cavity to induce more rapid cooling at that point and thereby produce hard zone i. CHILL TEST — Method of determining the suitability of a gray iron for specific castings through its chilling tendency, as measured from the tip of a wedge shaped test bar. Includes degating, tumbling, or abrasive blasting, grinding off gate stubs.
COD — A sand projection left behind in the mould by some patterns. Strictly speaking it is a core. COPE — The upper or top most section of a flask, mould or pattern.
COPE false — A temporary cope which is used only to establish the parting line. CORE — Separable part of the mould, usually made of sand and generally baked, to create openings and various shaped cavities in the castings. Also used to designate the interior portion of an iron base alloy which after case hardening is substantially softer than the surface layer or case.
CORE ram up — Core attached to the pattern and rammed up in the mould, where it remains when the pattern is withdrawn. CRUSH — Casting defect appearing as an indentation in the surface due to displacement of sand in the mould, usually at the joint surfaces. CUTS — Defects in castings resulting from erosion of the sand by the molten metal pouring over the mould or core surface. DIRT — Any extraneous material entering a mould cavity and usually forming a blemish on the casting surface. DRAFT — Taper allowed on the vertical faces of a pattern to permit removal of it from the sand mould without excessive rapping or tearing of the mould walls.
DRAG — The lower or bottom section of a mould or pattern. FEED HEAD — A reservoir of molten metal provided to compensate for contraction of metal as it solidifies, by the feeding down of liquid metal to prevent voids. They reduce shrinkage cracks and erosion of sand at sharp intersections.
Casting FIN — A thin piece of metal projecting from a casting at the parting line or at the junction of the cores or of cores and mould etc. FLASH — Thin fin or web of metal extending from the casting along the joint line as a result of poor contact between cope and drag moulds.
Cracks show up as fluorescent lines. GAS HOLES — Rounded cavities caused by generation or accumulation of gas or entrapped air in a casting, holes may be spherical, flattened or elongated. GATE — The location where the molten metal enters the casting cavity. The only pressure applied is that exerted by the head of metal in the pouring gate. It is used in cases where the runner does not enter the mould direct.
After the moulding medium has solidified, the pattern is removed by heating the mould, leaving a cavity for reception of molten metal. LOAM — A course, strongly bonded moulding sand used for loam and dry sand moulding.
Coatings of loam are applied to form the mould face. MATCH — A form of wood, plaster of paris, sand, or other material on which an irregular pattern is laid or supported while the drag is being rammed. Materials include graphite, silica flour etc. Each section incorporates a complete gate for casting.
All castings are poured from a central downgate. Such allowances are made by the pattern-maker. In a short period of time, the mass sets or hardens sufficiently to permit removal of the pattern.
The mould so formed is baked at elevated temperature to remove, all moisture prior to use. Small patterns may be cast solid, but large ones are usually produced by laminating with glass cloth.
Casting RAPPING BAR — A pointed bar or rod made of steel or other metal, which is inserted vertically into a hole in a pattern or driven into it, then struck with a hammer on alternate sides to cause vibration and loosening of the pattern from the sand.
RIBS — are used primarily as stiffeners and reinforcing members. If properly designed and located in difficult castings, serve to check the possibility of hot tears or cracks during solidification. RISER — Reservoir of molten metal attached to the casting to compensate for the internal contraction of the casting during solidification. SAG — Defect which appears as an increase or decrease in metal section due to sinking of sand in the cope decreased section or sagging in the core increased section.
Used to clean castings, to cut, polish or decorate glass and other hard substances. SCAB — A blemish on the casting caused by eruption of gas from the mould face. SEAM — Surface defect on a casting similar to a cold shut, but not as severe. SHOT — Abrasive blast cleaning material. The pattern and the shell are then heated further to harden or polymerize the resin sand mix, and the shell is removed from the pattern.
It is applied to the trowelling of a sand surface. SNAG — Removal of fins and rough places on a casting by means of grinding. SPRIGS — Small pegs of wood or metal used to strengthen weak portions of a mould or to assist in the mending up of a damaged mould. They are placed on top of the other and moulds stacked one over the other are poured through a common sprue.
They may also be used to shape sand surfaces into any required shape. VENT — Channel made in the sand in the vicinity of a mould to allow steam, gases etc. In the oven the wax is melted out leaving a vent or passage. Also refers coating materials applied to moulds, cores etc.
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.
ARC WELDING — A group of welding processes which produces 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. Shielding is provided by hydrogen. BORAX — is the old standard flux for brazing, exists in two forms—ordinary borax and amorphous or fused borax.
The filler material is distributed in the joint by capillary action. COVER PLATE eye protection — A removable pane of colourless glass, plastic coated glass or plastic that covers the filter plate and protects it from weld spatter, pitting or scratching when used in a helmet, hood or goggles. Shielding is by inert gas.
The weld pool is shielded by slag. During welding, a stationary electrode is consumed as the arc travels the length of the electrode. It consists of a small pore or inclusion surrounded by an approximately round bright area.
FLOW WELDING — Process which produces coalescence of metals by heating them with molten filler metal poured over the surfaces to be welded until the welding temperature is attained and until sufficient filler metal has been added.
FLUX — Material used in welding to prevent, dissolve or facilitate removal of oxides and other undesirable surface substances. Shielding is by the flux contained within the tubular electrode. FUSION — Melting together of filler metal and base metal substrate or of base metal only which results in coalescence. Shielding is obtained entirely from an externally supplied gas.
Shielding is effected by a gas or gas mixture. Shielding is obtained by external gas supply. Shielding is effected by a gas. Shielding is obtained from a gas. GAS WELDING — Process in which heat is furnished by a flame resulting from the combustion of a fuel gas, such as acetylene or hydrogen with oxygen; oxyacetylene being capable of producing the highest temperature flame is the most used.
A hand shield is equipped with a suitable filter plate and is designed to be held by hand. HELMET eye protection — Device designed to be worn on the head to protect eyes, face and neck from arc radiation, radiated heat, spatter, or other harmful matter expelled during arc welding. Vacuum or other shielding media is used. KERF — Width of the cut produced during a cutting process. This is confined to joining comparatively small work such as joints in wire.
The preheat to start cutting is obtained by other means. Shielding is obtained from the hot ionized gas issuing from the orifice which may be supplemented by an auxiliary source of shielding gas. SEAM WELD — A continuous weld between or upon overlapping members, in which coalescence may start and occur on the faying surfaces, or may have proceeded from the outer surface of one member. The advance of the welding is manually controlled. Also called hard soldering or silver soldering.
The hole may be open at one end. Pressure mayor may not be used. SPOT WELD — Weld made between or upon overlapping members in which coalescence may start and occur on the faying surfaces or may proceed from the surface of one member.
The weld cross section plan is approximately circular. Welding may be effected by arc, resistance, friction or other suitable process, with or without external gas shielding. SURFACING — Application by welding, brazing or thermal spraying of a layer s of material to a surface to obtain desired properties or dimensions as opposed to making a joint. No shielding is used. 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.
Aging is also used to increase dimensional stability in metals such as castings. Annealing is used to improve machinability and to remove stresses from weldments, forgings and castings. Also used to remove stresses resulting from cold working and to refine and make uniform the microscopic internal structures of metals. ANODIZING — To subject a metal to electrolytic action, as takes place at the anode of a cell, in order to coat it with a protective or decorative film, used for nonferrous metals.
Means of protecting iron from oxidation at elevated temperatures. The metal is held at a temperature above the transformation range for a period of time.
This is generally followed by quenching to produce a hardened case. HARDENING — Process of increasing the hardness of a ferrous alloy by austenitizing and quenching, also the process of increasing the hardness of some stainless steels and non-ferrous alloys by solution heat treatment and precipitation. The alloy is then allowed to cool slowly in air through the range of martensitic formation.
By this, surface hardening is achieved by the absorption of nitrogen without quenching. Usually done to clean and brighten the surface, although sometimes used for etching. QUENCHING — Rapid cooling of a metal in a bath of fluid during heat treatment after it has been heated to a given temperature, thus trapping the molecules of the metal in the desired structure.
The alloy is then cooled quickly to hold the constituent in solution, causing the metal to be in an unstable supersaturated condition. This condition is often followed by age hardening. It is a vector quantity. The sum is called their resultant and the vectors are called the components of the resultant.
DISC CAM — An irregular disc rotating about a fixed axis and imparting reciprocating or oscillating motion to a follower in a plane at right angles to the cam axis. FORCE — The entity which when acts on a body can cause a change in its velocity or direction or both. GOVERNOR — Device that controls the mean speed of an engine over a period of time, as distinct from the flywheel, which limits the fluctuation of speed during one cycle but is not able to prevent a change in mean speed from cycle to cycle.
Helix is the locus of a point which rotates about an axis at a fixed distance and at the same time moves parallel to the axis. Occur in collisions, in explosions, in the striking of a nail by a hammer or of a pile by a tup or monkey.
INVOLUTE — The locus of a point on a straight line which rolls, without slipping, on the circumference of a circle, or alternatively the locus of a point on the chord which is held taught and unwound from a cylinder.
LINK — Name given to any body which has relative motion to another. LOWER PAIRS — Types of kinematic pairs, namely two elements have surface contact and when relative motion takes place, the surface of one element slides over the surface of the other element. MACHINE — A combination of resisting bodies, with successfully constrained relative motions, which is used for transmitting or transporting available energy so as to do some particular kind of work e.
This results from a change in the direction of its linear velocity. The coupling transmits a constant velocity ratio. PAIR — Two bodies in contact constitute a pair. RACK — A portion of a gear wheel which has an infinitely large number of teeth. All other mechanisms, or those consisting of more than four links are compound mechanisms. Compound mechanisms are usually made up of combinations of simple mechanisms. A body has spherical motion if each point in the body has spherical motion.
This results from a change in its linear velocity. Vector quantities are represented by a straight line with an arrow head magnitude is represented by its length and direction by the arrow head. The chains pass over sproket wheels at the top and bottom of the elevator, and lift barrels from a loading platform to a runway. BAY — An area used for the open storage of heavy items. They include drive, terminal or bend, take up and snub pulleys.
BIN — An enclosed space for storing certain types of goods. BRAKE — Arrangement in the hoisting machinery to stop the load and hold it when applied to the hoisting motion or bring the relevant mechanisms at rest within specified braking distances. May be a band brake, disc brake or a cone brake. The worker stays in one place while the needed item comes to the work station. Chain conveyors carry aprons, pans, buckets, cradles, pockets, cars etc.
A mechanical device for carrying packages or bulk material from place to place as by an endless moving belt or a chain of receptacles. CRANE — A machine for raising, shifting and lowering heavy weights by means of projecting swinging arm or with the hoisting apparatus supported on an overhead track. This is dead zone.
DRUM — In hoisting unit, a device for spooling the rope in one layer or in more than one layer. It is an inclined conveyor with the driving traction in the form of steeps attached to step drive chains and each escalator step is carried on four wheels riding on tracks. During its manufacture, every strand laid from wires of circular cross—section is radially squeezed over the circumference so as to flatten the wires.
FLEX — Flow tank car. A pressurized tank car that can unload in a few minutes. GRAB — Device suspended from the crane hook which grasp and release the load of given shape and size at almost no time.
Suitable for handling of unit loads and containerized high volume materials. HOOK — Multipurpose attachment widely used in hoisting installations, carries the load by one or more of slings made of hemp ropes or chains. JACK — Device used to lift loads through a short height some 0. LIFT — Hoisting equipment adapted to lift loads vertically.
Widely used in handling steel and cast iron loads. It may be a simple pincer or complicated robot. The platform has an upper and lower flat surface with space between for the forks of an industrial lift truck.
Includes combinations such as diesel electric, electro hydraulic, electro pneumatic drives. RACK — A storage place for individual items or palletized loads.
RAIL ROAD CRANE — Crane mounted on a truck meeting railroad requirements and supported by axles of varying number used for load handling and wreckage clearing purposes, carry a power unit which is a combination of a diesel, a generator and a number of electric motors.
SCRAPER — Machine that removes earth slice by slice, transports and places it in an earth structure, or pushes it to a dump and then levels the same. SEAL — A small metal strip that is placed on a railroad car door when loading is completed. SHAKING CONVEYOR — Unit which consists of a deck in the form of a trough or pan suspended from, or supported by a stationary frame and the deck is induced to oscillate, causing the material to move along at a pace and in a mode governed by the character of the oscillations, e.
SKID — Similar to pallets except it has no bottom surface. Used for vertical movement of coal. Unit load is pulled on it and the forks of the lift truck slide underneath. SOFC — A container stacked on a flat car. SPAN — Horizontal distance between the axes of crane track rails. They are usually centrifugal brakes e. The movement of the screw gradually moves the material to a higher location.
TRACTOR — A crawler or wheel mounted, self propelled vehicle designed to perform agricultural, earthmoving, road making, load carrying and other work.
To lift a load, the vacuum cup is applied to its surface, and the vacuum generator is set into operation, creating a vacuum in the cup. It is the same as the friction angle. These have a greater affinity for oxygen than does the oil. Bearing consists of an inner and outer hardened steel races separated by a series of hardened steel balls. Area of the unit in which the contacting surface of a revolving part rests.
This ensures complete contact of the bearing back with the housing bore when the unit is assembled. Through this space lubricating oil can flow. Preload is usually adjusted by a threaded collar or shims. A one piece replaceable sleeve placed in a bore to serve as a bearing surface. Bearing for shaft, spring shackle, piston pin etc. A metallic or synthetic lining for a hole.
As the oil passes through the slinger, centrifugal force removes impurities that are heavier than oil. Accumulation of unburned gasoline in the crankcase. After the oil has been pumped through four stroke cycle engine, it is returned to the oil tank by return side of oil pump.
It is a rough indication of the tendency of the oil to vapourize. FRICTION — The force which acts between two bodies at their surface of contact so as to resist their sliding on each other, due to roughness of the surfaces.
Sleeve bearings, such as those used in connecting rods, are friction bearings. To this mixture fillers may or may not be added. Rollers have a length over four times greater than their diameter. OIL — A liquid lubricant derived from crude oil used to provide lubrication between moving parts. It may be paper, wire screen or rotor designed to keep oil clean. OIL PAN — The detachable lower part of the engine made of sheet metal, which encloses the crankcase and acts as an oil reservoir. SEAL — A material, shaped around a shaft, used to close off the operating compartment of the shaft, preventing oil leakage.
SEIZING — The phenomenon in which the metal surfaces adhere and then tear owing to relative motion, caused by the attraction between molecules on opposite sides of the common surface between two elements of a bearing. Friction, Lubrication and Bearings SHIM bearing — A strip of copper or similar material used under a bearing cap, for example, to increase bearing clearance.
SLUDGE — Accumulation in oil pan, containing water, dirt and oil, sludge is very viscous and tends to prevent lubrication.
The engine is enclosed, and the crankcase contains oil into which the cranks dip and splash as they rotate, throwing the oil over the various bearings.
SUMP — A system for storing oil, either in the crankcase wet sump or in a separate tank dry sump. Oiliness of the lubricant is important in this type of lubrication. The thickness of an oil is determined by its rate of flow, a thick oil has a greater viscosity than a thin oil. Unit of viscosity is centipoise. A point which has been determined on the thermodynamic scale by theoretical considerations beyond which a further decrease in temperature is inconceivable.
This is equal to — In this system no heat transfer takes place i. It can however exchange work with the surroundings. AIR — A gas consisting principally of a mechanical mixture of It is generally taken as 1.
A black body emits the maximum amount of radiation possible at a given temperature, and the amount is proportional to the fourth power of the absolute temperature. Now the saturation pressure of the vapour equals that of the atmosphere.
The boundary may be a fixed one or a varying one. Or conversely, the volume will vary inversely as the absolute pressure, if the temperature remains constant. CELSIUS — The scale of changes of temperature which uses 0 degree as the freezing point and degree as the boiling point for water at standard pressure.
At constant volume, the pressure is proportional to its absolute temperature. COLD — A comparative lack of heat, indicating chillness. There will be no workdone by the gas. The whole heat supplied will be stored in the form of internal energy. Heat supplied to a system exhibits as the change in enthalpy. There is no change in temperature and hence internal energy and enthalpy remain constant. Also transfer of heat to or from a fluid liquid or gas flowing over the surface of a body.
At critical state, latent heat of evaporation becomes zero. It may be either saturated or superheated steam. In other words the output divided by the input. Examples are volume, weight and total energy.
GASES — are substances in which the molecules move freely and exist in an unbound state. Gases can be compressed easily because of the large empty space available between the molecules. HEAT — A form of energy and is due to the motion of the molecules of which all substances are composed. Unit of heat is kilocalorie. It has the same numerical value as the heat of vapourization. It transforms heat energy into mechanical energy and render the latter available for doing useful work. HEAT PUMP — is a device which extracts heat from low temperature surroundings and sends it to a high temperature body, while operating in a cycle.
Heat pump maintains a body or system at a temperature higher than the temperature of the surroundings, with the work supplied to it. For an ideal gas, the internal energy and enthalpy are functions of temperature alone. It is the energy stored in the gas and is used for raising its temperature. Example are pressure, temperature and density. In this system, no mass transfer, no energy transfer occur.
Work and heat cannot cross the boundary of the system. As temperature changes, the internal energy also changes. The kinetic energy of a moving body is the work which the body is capable of performing against a resistance before it is brought to rest, that is, it equals the work which has brought it from its state of rest to its actual velocity. Also, the amount of heat energy in a gas which is in addition to that found in the liquid at the same temperature.
However, it can be stored in various forms and can be transferred from one form to another. In other words, the total energy of a body or substance always remains constant. A definite volume is maintained by the bond forces, but can change the shape according to the shape of the container. MATTER — General name for all material substances, gaseous, liquid or solid forming the earth and its surrounding atmosphere.
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