Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Ch"

CH3CCl3: Symbol for Methyl chloroform

CH3OH: Symbol for Methanol

CH4: Symbol for Methane

Chafer: The area between the bead and sidewall of a tire.

Chafer strip: The area between the bead and sidewall of a tire.

Chafing plate: A bent plate for minimizing chafing of ropes

Chain: Chain

Linked, flexible metal "rope" that connects two sprockets (e.g., the chainwheel to the back wheel cogs, sized differently for different types of bikes.) The teeth of the sprockets fit inside the spaces between the links. Also called a roller chain.
Also See
cam chain
derailleur chain, narrow width
derailleur chains
double roller chain
drive chain
duplex chain
O-ring chains
primary chain
safety chains
silent chain
simplex chain
single roller chain
snow chains
timing chain
tire chains
triplex chain

Chain breaker: Chain Breaker

A tool for removing the pins in a roller chain so that the links can be removed.

Chaincase: An enclosed metal covering which encircles the drive and driven sprockets as well as the chain.

Chain case: See
chaincase

Chain drive: A system of transferring power from one shaft to another by means of sprockets and an endless chain. This is the system used on a bicycle; but it is also used on an engine to control the timing of valve opening (called " timing chain" or " cam chain").

Chain filter wrench: A chain wrench which encircles the oil filter to assist in its removal.

Chain guard: A metal or plastic covering for the top run of a chain. It is most often found on bicycle chains where the guard keeps your clothing from being caught in the chain or even from getting greasy.

Chain hoist: A lifting device which uses a chain and block and tackle to lift large objects like engines.

Chain locker: A compartment for the stowage of anchor chain

Chain pipe: A pipe for passage of chain from windlass to chain locker

Chain pipe wrench: Chain Pipe Wrench

A chain wrench which circles around a pipe and grips it so that the pipe can be tightened or removed.

Chain quick link: Chain Quick Link

A fastener which holds two ends of large chain and by un-screwing the nut, the link can be removed or installed at will.

Chainring: Chainring

One of the sprockets attached to the right crankarm of a bicycle to drive the chain. Also called chainwheel."

Chainring bolt: The 4 or 5 bolts that attach the chainrings to the crankarm of a bicycle

Chainring bolt circle diameter: The configuration of the bolt pattern on a chainring. Draw a circle through the center of all the bolt holes used to connect the chainring to the crankarm and measure the diameter of the circle (in millimeters). On a road crankset with two chainrings, they will both use the same bolt circle diameter. Typical bolt circle diameters are 130 or 135 mm on road bikes.

Chainring nut spanner: A special bicycle tool used to loosen the slotted nuts that fasten a chainring to a crankarm.

Chainring teeth: The number and type of teeth (i.e., pointed projections which are forced between the rollers of a chain) in a chainring sprocket. A typical large road bike chainring has 53 teeth cut into its surface and it is referred to as a size 53.

Chain run: The distance between the front and rear sprockets.

Chains: See
chain

Chain scrubber: A device attached to a chain which rubs away the grime while the chain is moving.

Chainstay: Chainstay

One of the two tubes of a bicycle frame that run horizontally from the bottom bracket shell back to the rear dropouts.

Chainstays: The two tubes of a bicycle frame that run from the bottom bracket back to the rear dropouts.

Chain stopper: A device used to secure the chain cable when riding at anchor, thereby relieving the strain on the windlass

Chain switch: See
snow chain switch

Chain tensioner: Chain tensioner

A device which takes up the slack in a chain. Some use an idler wheel which can be adjusted (manually or automatically), others use a flat slide which pushes against the chain to keep it from bouncing around. Most modern units are spring loaded so that the tensioner automatically takes up the slack. Some require that you need to undo a locking nut to allow the spring to push against the chain. Afterward the lock nut needs to be secured again.

Chainwheel: Chainwheel

One of the sprockets attached to the right crankarm of a bicycle to drive the chain. Also called chainring."

Chain whip: A tool consisting of a metal bar and two sections of chain, used in changing cogs on a freewheel. Sometimes called "chain wrench."

Chain wrench: Chain Wrench

A locking pliers which employs a chain to wrap around an object such as a pipe to secure or remove it.

Also See
chain whip

Chair: Motorcycle sidecar

Chalking: The appearance of a white powder on a paint surface as it weathers and ages.

Chamber

A pressure chamber used to vulcanize pre-cured tread stock to the buffed casing.
A compartment which is basically empty or hollow.

Also See
climatic chamber
combustion chamber
exhaust chamber
fireball combustion chamber
float chamber
gas chamber
hemispherical combustion chamber
humidity chamber
main combustion chamber
mixing chamber
pent-roof combustion chamber
plenum chamber
pre-chamber
pre-combustion chamber
pre-compression chamber
pumping chamber
salt spray chamber
spherical combustion chamber
suction chamber
swirl chamber
twin swirl combustion chamber
vacuum chamber
wedge combustionchamber

Chamber recess: See
combustion chamber recess

Chamber volume: See
combustion chamber volume

Chamfer: To bevel or taper the edge of an object especially the sides of a hole or a sharp corner

Chamfered: A chamfered object is one that has a symmetrically bevelled edge.

Chamois: Pronounced SHAM-mee. A soft piece of animal skin (from a deer, sheep, goat, etc.) used to absorb water after washing the surface of a vehicle. Also called a chamois leather or shammy leather.

Chamois leather: See
chamois

CHAMP: Acronym for Certification of Higher-learning in Alternative Motorfuels Program

Champ car: When Championship Auto Racing Teams (CART) was co-sponsored by Fed_Ex, the series became known as the Fed_Ex Championship Series for the PPG Cup. The cars in this series, previously known as Indy Cars, are called Champ Cars.

Change: To remove something and replace it with something else.

Also See
climate change
downward change
floor change
oil change
range-change
upward change

Change down: A British expression meaning to shift to a lower gear.

Change gear: The action of selecting a different gear. This expression is used more in Britain than in North America where the expression is "shift gear."

Change into: A British term for the action of shifting into another gear, such as "change into second" (shift into second gear) or "change into top" (shift into high gear)

Change of state

Rearrangement of the molecular structure of matter as it changes between any two of the three physical states solid, liquid, or gas
Condition in which a substance changes from a solid to a liquid or a liquid to a gas due to addition of heat. Or, the reverse, in which a substance changes from a gas to a liquid, or a liquid to a solid, due to removal of heat.

Changeover

The refitting of equipment to either neutralize the effects of the just completed production or to prepare equipment for production of the next scheduled item, or both.
The removing of new original equipment tires in exchange for a different make, size, or type.

Changer: See
CD changer
column changer
column gear changer

Change-speed gearbox: A transmission which houses a set of gears which move into various configurations of engagement in order to produce different output ratios.

Change the oil: The act of draining out the old or dirty oil from an engine and replacing it with fresh oil.

Change up: A British term meaning to shift up to another gear

Change valve: A British term for a valve in an automatic transmission which raises the oil pressure as the vehicle speed increases. In North America it is called the shift valve.

Changing: See
charge changing
wheel changing

Channel

To lower the vehicle body around the frame.
A route or groove through which anything passes.
The hydraulic routing used by the anti-lock brake system to control the brake pressure at each wheel. A system may have one, three, or four channels

Also See
chassis channel
distribution channel
glass channel
grip channel
runabout run channel
run channel
window channel

Channelled: Vehicle body lowered down around the frame.

Channel section: A long metal U-shaped member used in the chassis.

Chap: See
tank chap

Chapman: Anthony Colin Bruce Chapman (1928-1982), the founder of Lotus. One of the most innovative engineer in automotive racing history.

Chapman strut: Click image to supersize
Chapman Strut

A type of rear suspension using a lower lateral link and a long spring-shock strut to determine wheel geometry. The basic principle is the same as that of the front Mac_Pherson strut and it is so named because Colin Chapman first used it on the original Elite; it is also used on the Elan models, the new Elite, and the Datsun (Nissan) Z-car.

Characteristic map: A three-dimensional picture showing the relationship between various components of a vehicle. With the help of a computer, engineers can modify one component to see the effect it has on the whole operation of the vehicle.

Characteristics of materials: See
performance characteristics of materials

Character line: The design line or bend in the side of the vehicle that separates the upper and lower sections of the fenders and doors

Charcoal: The amorphous form of carbon obtained by the destructive distillation of animal or vegetable matter in a limited supply of air. In automotive use, it is used to purify air or exhaust gases.

Also See
activated carbon
activated charcoal

Charcoal canister: Another name for activated carbon canister

Charcoal filter: A filtration system using activated carbon to remove impurities.

Charcoal trap: See
activated charcoal trap

Charge

The action of passing an electric current through a battery to restore it to the active (charged) state. Normally the vehicle's generator or alternator takes care of this. If the vehicle is not used much, an external charger is needed to charge the battery.
The definite quantity of electricity usually found in a storage battery.
Refers to the mass of air and fuel that enters a cylinder during the intake stroke.
A refund amount of money.

Also See
core charge
Amount of refrigerant placed in a refrigerating unit.
A specific amount of refrigerant by volume or weight

Also See
air charge temperature
battery charge
catalyst charge
core charge
cylinder charge
electric charge
fuel charge
intake charge
state of charge
stratified charge
trickle charge

Charge air: The air/fuel mixture.

Charge air cooling: An intercooler

Charge-air recycling: A device on a turbocharger which maintains the speed of the compressor when there is no boost so that the boost is more instantly available on demand.

Charge capacity: The input (feed) capacity of the refinery processing facilities.

Charge changing: In a two-stroke engine, the removal of exhaust gases through the exhaust port in order to introduce a new load of fuel-air into the transfer port. Also called "charge exchange process."

Chargecooler: A radiator that cools and therefore recondenses the intake air that has been compressed and heated by the turbocharger thus allowing a greater amount of air into the engine. With more air in the combustion chamber, the ECM can deliver more fuel and make more power. This radiator can be either cooled by air or by water. Also called intercooler

Charged: See
dry charged battery

Charged battery: See
dry charged battery

Charge engine: See
stratified charge engine

Charge exchange process: Another name for charge changing

Charge indicator: See
battery charge indicator

Charge losses: In a two-stroke engine, the exhaust gases are expelled out the exhaust port and the fresh charge is brought in through the transfer port. Sometimes some of the fresh charge is also forced out with the exhaust gases. There is therefore a loss of some of the fresh air-fuel charge.
Also See
scavenging losses

Charger: Common name for a battery charger.
Also See
fast charger
trickle charger
turbo charger

Charges: See
on-the-road charges

Charge temperature: See
air charge temperature

Charging: See
battery charging
piston charging pump
slow charging

Charging board: Specially designed panel or cabinet fitted with gauges, valves, and refrigerant cylinders used for charging refrigerant and oil into refrigerating mechanisms.

Charging characteristic: When a battery is being charged, the charger will reveal how much voltage and/or amperage is being required to bring the battery up to full charge.

Charging circuit: See
charging system

Charging current: The amount of electric current being supplied to the battery from the alternator or from a battery charger.

Charging efficiency

In a vehicle's electrical charging system, its efficiency is the ratio of energy output to energy input, i.e., how well does the alternator work to supply voltage to the electrical components and still charge the battery.
In a two-stroke engine, it is the ratio of the amount of the fresh charge that remains in the cylinder after the two ports are closed and the actual volume.

Charging hose: A small diameter hose constructed to withstand high pressures. It is connected between the air conditioning system and the manifold set

Charging piston: In a two-stroke engine, this is a secondary piston which precompresses the fresh charge and sends it into the cylinders

Charging point: A place where a battery can be charged -- especially for battery-powered electrical vehicles. Also called battery charging station

Charging pressure: See
boost pressure

Charging pump: See
piston charging pump

Charging rate: The amount of electrical current which is delivered by the charging system. It is usually measured in amperes.

Charging station: A usually portable unit equipped with a manifold gauge set, charging cylinder, vacuum pump, refrigerant supply, auxiliary gauges, various valves and the plumbing necessary to hook everything together. Used for servicing air conditioning systems.Also see battery charging station

Charging stroke: See
induction stroke

Charging system: A system that, using a fan belt driven by the engine, enables the alternator (or generator) to generate electrical current, which is stored in the battery and delivered to the electrically operated pars of the vehicle chassis The parts of the vehicle which are left when the body and fenders are removed.

Charles's law: Volume of a given mass of gas at a constant pressure varies according to its temperature.

Charpy test: An impact resistance test in which the specimen is supported as a horizontal beam and broken by a single swing of a pendulum with the impact line midway between the supports and directly opposite the notch for notched specimens.

Chart: See
color chart

Chase: To repair damaged threads on a bolt or nut with a tap or die

Chassis: Generally, chassis refers to the frame, engine, front and rear axles, springs, steering system, fuel tank. In short, everything but the body or cab and fenders. Because most modern automobiles (apart from trucks) do not have a separate chassis, the body is sometimes called the chassis.
Also See
backbone chassis
cab chassis
cowl chassis
ladder chassis
mid-engine chassis configuration
punt chassis
separate chassis

Chassis bracket set: When the sill panel does not have a jointing flange, a set of securing pieces are welded under the sill before straightening a bent or damaged sill.

Chassis cab: A truck with a cab but no bed. To this system various bodies (ambulance, moving van, flat beds, etc.) can be added by aftermarket suppliers.

Chassis channel: A channel section which makes up a member of the chassis.

Chassis configuration: See
mid-engine chassis configuration

Chassis dynamometer: A test stand for a vehicle to determine its power output or emission levels, etc. when the vehicle is placed under a variety of driving conditions.
Also See
dynamometer

Chassis frame: A frame (found on large trucks) which is made up of two long side members which are joined by several crossmembers. The suspension and axles are attached to this frame.

Chassis leg: The short channel or box section which runs along the vehicle's main axle. It is an auxiliary member, not the main side member.

Chassis lubrication: See
central chassis lubrication

Chassis number: The serial number of an older vehicle which was originally stamped on a chassis member. Later it became known as a vehicle identification number (VIN)

Chassis section: One of the chassis channels or boxes, whether bolted or welded to the whole.

Chassis weight: The weight of an empty truck, without occupants or load. Also called Curb Weight or Tare Weight

Chatter

A noise which is caused by an irregular movement of rattling parts.
The jerky movement of two components which may have moved in a systematic way under low speed; but as the speed increases, the components make irregular contact.

Also See
contact bounce
contact chatter

Check

An inspection to determine if everything is functional.
A slight slash or marking which may appear in a tire or upholstery.

Also See
checking
compression check
door check arm
door check strap
optical check

Check arm: See
door check arm

Check ball: A small ball (like a ball bearing) often made of metal or plastic, found in a check valve to halt the progress of fluid in a certain direction.

Check engine light: A light on the instrument panel that lets the driver know of any detectable engine management system malfunctions. Also used as an emission maintenance reminder light on some vehicles. Often when this light is on, a trouble code is stored in the computer. Also called malfunction indicator light"

Check engine warning light: An light on the dash which is illuminated when one of the engine sensors or components does not function properly.

Checkered flag: A flag with alternating black and white squares to signal the end of the race.

Checking

Short, very fine crack lines that appear in the paint film.
Small cracks in the surface of rubber (e.g., tires) caused by aging and oxidation.
Also See
ozone checking

Check point

A designated spot on a component where it is possible to determine if there is a malfunction.
A place on the road where vehicles are stopped during a rally.

Check routine: A series items in an inspection which traces a fault or problem or which determines if all the components of a new vehicle meets the required specifications.

Check stop: An action taken by the police to stop vehicles in order to determine if the drivers have been drinking, wearing seat belts, and conforming to the other requirements of operating a vehicle.

Check strap: See
door check strap

Check the battery: Determine if the electrolyte is at the correct level and add distilled water to bring it up if necessary

Check the oil: Using a dipstick, determine if there is sufficient oil in the crankcase

Checkup: The process of discovering the reliability of a vehicle or its components. "Give my engine a checkup." Sometimes it means tune-up."

Check valve: A one-way, in-line valve that permits flow of liquids or gases in one direction only and closes to prevent passage in the opposite direction. Used to control flow of vacuum, refrigerant, coolant, etc.

Also See
closed type check valve
open type check valve
residual pressure valve
residual brake pressure type check valve
two-way type check valve

Cheese head: A cylindrical head for a screw with a straight slot and straight sides.

Chemical activation: Treatment of a substance by heat, radiation, or other activating reagent to produce a more complete or rapid chemical or physical change.

Chemical brightening: The improvement of the smoothness of the surface of metal by immersing it into a solution designed to remove any roughness. Also called "chemical polishing."

Chemical cure: Vulcanization at room temperature or above, activated by chemical agents without the application of heat from an outside source.

Chemical curing: The setting or curing of an adhesive, coating or sealer, brought about by the addition of heat, a catalyst, or an accelerator

Chemical polishing: See
chemical brightening

Chemical refrigeration: System of cooling using a disposable refrigerant. Also called an expendable refrigerant system.

Chemical separation: A process for extracting uranium and plutonium from dissolved spent nuclear fuel and irradiated targets. The fission products that are left behind are high-level waste. Chemical separation is also known as reprocessing.

Chemical staining: Spotty discoloration of the paint caused by air pollution in industrial areas

Chemical toilet: A portable toilet which is used in campers and motorhomes. They contain chemicals to deal with the feces and its smell until the contents are dumped.

Chenard-Walcker: A vehicle brand of which the 1925-1948 models with required application are classic cars.

Cheney® Clamp: A screw-type hose clamp similar to a Jubilee® clamp

Cherry: A colloquial term for a vehicle that has been kept in, or restored to, perfect condition. Also called "mint" or "like new."

Cherry condition: A colloquial term for a vehicle that has been kept in, or restored to, perfect condition. Also called mint condition."

Chest: See
sea chest

Chevelle: Click image for books on
Chevelle

An intermediate model automobile produced by Chevrolet from 1964 to 1983 (the last few years being called "Malibu")

Chevrolet: Click image for books on
Chevrolet

A vehicle brand of which the 1955-57 Bel Air V-8 Hardtop and Convertible are milestone cars.

Chevrolet Camaro: Click image for books on
Chevrolet Camaro

A vehicle brand of which the 1967-69 SS/RS V-8 and Z-28 models are milestone cars.

Chevrolet Celebrity: See
Celebrity

Chevrolet Chevelle: See
Chevelle

Chevrolet Corvair: Click image for books on
Chevrolet Corvair

A vehicle brand of which the 1960-64 Monza models are milestone cars. The 1962-64 Monza Spyder models are milestone cars. The 1965-69 Monza/Corsa models are milestone cars.

Chevrolet Corvette: Click image for books on
Chevrolet Corvair

A vehicle brand of which the 1953-70 models are milestone cars. See also a history of the Corvette

Chevrolet Malibu Hybrid: A midsize hybrid sedan similar to the Saturn Aura Green Line that uses a Belt Alternator Starter hybrid system.

Chevrolet Monte Carlo: See
Monte Carlo

Chevrolet Nomad: A vehicle brand of which the 1955-57 models are milestone cars.

Chevrolet Nova: See
Nova

Chevrolet type: A dual mounting wheel type consists of one cone locking nut on each stud that holds both wheels in place against the hub.

Chicken coop: Trucker slang for Truck weigh station as in "Are the chicken coops open this morning?"

Chicken lights: Trucker slang for Extra lights on a truck as in "Look at all those chicken lights on that northbound bulldog."

Child bike seat: Child Bike Seat

An accessory which mounts behind the saddle of a bicycle and is designed to hold a small child.

Childproof lock: On the rear doors of a car, a specially designed locking device can be set to normal or to childproof. When set to childproof, the door cannot be opened from the inside.

Child restraint system: A term for a number of items which are designed to protect children from injury during an accident (such as child seats).

Child safety: See
integrated child safety seat

Child safety seat: See
integrated child safety seat

Child seat: A small safety seat which is mounted on a regular car seat and is held in place by the seat belt.

Also See
integrated child seat

Child step running board: Clild Step Running Board

An external step which allows a child to be able to enter or leave a vehicle with a high ground clearance (a van, SUV, truck, etc.)

Chilled iron: cast iron possessing a hardened outer skin.

Chiller: Air conditioning system which circulates chilled water to various cooling coils in an installation.

Chill factor: Calculated number based on temperature and wind velocity.

Chimney: Vertical shaft enclosing one or more flues for carrying flue gases to the outside atmosphere.

Also See
coil tower
coil chimney

Chimney connector: Conduit (pipe) connecting the heating appliance (furnace) with the vertical flue.

Chimney effect: Tendency of air or gas to rise when heated.

Chimney flue: Flue gas passageway in a chimney.

Chip

Small pits in the glass (windshield or headlight) or in the paint caused by small flying stones.
To cut with a chisel.
A collection of sample paint.
Also See
paint chip book

Chip book: See
paint chip book

Chip damage: See
stone chip damage

Chip hammer: Chip Hammer

A hammer used to remove slag, etc. from metal because it has a chisel-like end on one side

Chipping: The action of tearing away small bits or flakes of paint or of rubber from the tread of a tire. When larger pieces of rubber tear away, it is called chunking.

Chipping hammer: Chipping Hammer

A hammer used to remove the slag from weld seams.

Chisel: There are two basic types of chisel. One is used for wood work (wood chisel) while the other is for metal work (cold chisel).

Also See
splitting chisel

Chisler: A vehicle buyer who constantly grinds the salesman to the obtain the best possible deal that he can get.

Chloride: See
calcium chloride
polyvinyl chloride

Chlorofluorocarbon

(CFC)

A gas compound which was used as a propellant in aerosol cans and in refrigerants.
Any of various compounds consisting of carbon, hydrogen, chlorine, and flourine used as refrigerants. CFCs are now thought to be harmful to the earth's atmosphere.

CHM: Acronym for cold mixture heater--A device which helps to reduce cold engine emissions and improve driveability during engine warm-up. Also CMH.

Chmsl: (pronounced CHIM-sel) An abreviation for "center high mounted stop light" an additional brake light as required by federal law whose mounting position is determined by the manufacturer using federal guidelines

Chock

A wedge used to prevent a wheel from rolling -- especially when replacing a tire/wheel. Also called a wheel chock."
A heavy smooth-surfaced fitting usually located near the edge of the weather deck through which wire ropes or fiber hawsers may be led, usually to piers.
Also See
boat chock

Choke: A butterfly valve or plate located near the top of the carburetor that limits or restricts the amount of air allowed to enter the carburetor, thus enriching the fuel-air mixture and enabling the vehicle to start and run more easily when cold. Automatic chokes have a thermostatic coil or thermostatic spring that activates a butterfly valve at the top of the carburetor barrel. Older cars have manually operated chokes. Some vehicles use an enrichner instead of a choke.
Also See
manual choke
radio choke

Choke stove: A flapper near the top of the carburetor which regulates the amount of air entering the carburetor.
Also See
choke

Choke control: A device or system for operating a non-automatic choke. It is usually a cable attached at one end to the choke butterfly and a knob on the dash at the other end.

Choke index: Automatic chokes have index marks. The factory setting closes the choke when the bimetal is about 21°C. If you want less or more choke at this temperature, move the choke index one mark in the direction indicated by the arrows designating a leaner or richer mixture. You will seldom need to move the choke more than one mark

Choke kick: A preset position for the choke valve set by manifold vacuum that is routed through a carburetor body passage to the choke diaphragm

Choke knob: A knob on the dash fascia which is part of the choke control system.

Choke stove: A heating compartment in or on the exhaust manifold from which hot air is drawn to the automatic choke device.

Choke thermal vacuum switch: (CTVS) a switch used on some GM vehicle to deny vacuum to either the front or the auxiliary choke vacuum breaks. Its purpose is to slow the opening of the choke and to provide better driveability when the engine is cold

Choke tube

The part of the carburetor air horn where the choke butterfly is positioned. Also called a carburetor venturi.
Throttling device used to maintain correct pressure difference between high-side and low-side in refrigerating mechanism. Capillary tubes are sometimes called choke tubes.

Choke valve: In a carburetor, it is the choke butterfly.

Chop: Lowering the height of some area of the vehicle roof, hood, top, etc.

Chopped wheel: Lightened flywheel.

Chopper

Chopper

Once used to describe a custom motorcycle that had all superfluous parts "chopped" off in order to make the bike faster. A chopper today is a type of custom bike that usually has an extended fork, no rear suspension, high handlebars and a lowered seat. Often the original fuel tank is changed to a smaller size.
To travel by motorcycle.

Chop shop

A garage which specializes in turning a two-door car into a convertible by removing the steel top.
An illegal garage which processes stolen cars by removing valued parts and selling them privately or by changing the serial numbers for illegal resale.

CHP

Acronym for combined heat and power
Acronym for California Highway Patrol

C/H Ratio: Acronym for Carbon/Hydrogen ratio

Christmas tree

A device, using a series of lights, to start cars on the timed 1/4 mile drag run.
The valves and fittings installed at the top of a gas or oil well to control and direct the flow of well fluids.

Chromate

A salt or ester of chromic acid which is often used as a paint pigment.
The action of treating metal with a solution of chromium compound to produce a protective metal chromate coating. Also called "chromatize."

Chromate coating: A conversion coating produced by chromating.

Chromate treatment: A solution of chromium compound is applied to metal to produce a protective coating of metal chromate.

Chromatic aberration

An enlargement of the focal spot caused in a cathode tube, by the differences in the electron velocity distribution through the beam.
An enlargement of the focal spot caused in an optical lens system using white light, by the refractive index of the glass varying with the wavelength of the light, resulting in colored fringes surrounding the image.

Chromatize: The action of treating metal with a solution of chromium compound to produce a protective metal chromate coating. Also called "chromate."

Chrome

A short form for chromium.
The chromium plating of metal on a vehicle.
To plate with chromium.

Also See
piston ring, chrome
ring, chrome

Chrome-hardened: Steel that has been made harder by adding chromium.

Chrome-moly: A type of high-quality steel tubing; also called "chrome molybdenum" or "cro-mo"

Chrome molybdenum: A type of high-quality steel tubing. Also called "chrome-moly" or "cro-mo"

Chrome-plated: In order to prevent iron from rusting and showing bright and shiny, the iron is coated with a layer of chromium by process of electroplating (or electrodeposition).

Chrome ring: A piston ring with a chrome face, i.e., a thin layer of chrome plate on the outer edge.

Chrome steel: In order to improve rust resistance and increase hardness, chrome is added to steel. Also called "chromium steel."

Chrome work: All the metal on a vehicle which has been plated with chrome.

Chromic acid: Electrolyte which is used in anodizing processes for producing non-transparent, non-metallic oxide layers.

Chromium: A very hard grey metal used in electroplating and the production of very hard steel compounds that are also resistant to rust.
Also See
hard chromium plating

Chromium-plated: A coating of metal with chromium to protect the metal from rust.

Chromium plating: The process of coating metal with a layer of chromium to prevent rust.
Also See
black chromium plating
hard chromium plating

Chromium steel: In order to improve rust resistance and increase hardness, chrome is added to steel. Also called "chrome steel."

Chro-mo: A type of high-quality steel tubing; also called "chrome molybdenum" or "crome-moly"

Chrysler: Click image for books on
Chrysler

A vehicle brand of which the 1926-30 Imperial 80, 1931 Imperial 8 Series CG, 1932 CG and CH, 1933 CL, 1934-6 CW with required application are classic cars. The 1970 300 Hurst is a milestone car. The 1955-65 300 Letter Series are milestone cars. The 1946-50 Town and Country models are milestone cars.

Chubby screwdriver: A British term for a screwdriver with a short handle and blade for reaching into confined spaces. In North America it is called a "stubby screwdriver."

Chug

The short explosive sound of an engine going steadily and rather slowly.
To make the sound of chug.
To drive slowly and steadily.

Chunking: The action which occurs when large pieces of rubber from the tread of tire breaks away. When small pieces break away, it is called chipping.