Work in Progress - please check back periodically!

Below you will find many of the terms associated with Steam Era freight cars (along with some misnomers that we hope to correct and eradicate from the popular lexicon). If you find that a phrase or term is absent, please let us know via email at, subject: Glossary. Thank you.



"A" Car Roof - A car roof with straight car lines, meeting at a point like rafters in the center of the upper deck. (CBC)

"A" End - The opposite end of the freight car from where the brake shaft is located. (CBC)

Air Brake - Any system of braking in which the mechanism is actuated by the manipulation of air pressures exerted on different parts of the apparatus. In the US, this covers only brakes that employ air under pressures above atmospheric as distinguished from "vacuum brakes" which employ pressures below atmospheric. (CBC)

"AB" Brake Equipment - The name designated for the type of brake equipment made standard for new freight cars built after Sept. 1, 1933, rebuilt cars after Aug, 1, 1937 and compulsory in interchange after Jan. 1, 1945 (revised to xx/xx/xx) by the Board of Directorsof the AAR upon recommendations of the General Committee of the Mechanical Division. Replaces Type "K". (CBC) Piping Diagram of Westinghouse AB Brake Equipment

AAR - Association of American Railroads - more coming

Ajax Brake Wheel & Housing - The most common geared brake wheel and housing during the late Steam Era - see photo.

Angle Cock - A special type of valve located at both ends of the brake pipe. The free opening is threaded to receive the air connecting hose nipple.

Arch Bar Truck - see Diamond Arch Bar Truck

Automatic Air Brake - An air brake system in which the brake will be applied automatically in case of an accident that permits air to escape from the system. (CBC)

Automobile Car - A box car for carrying automobiles and having exceptionally large side doors (usually double) at least 10 ft. wide and sometimes end doors. Inside length is commonly 40ft. 6 in. or 50 ft. 6 in. and a clear height of at least 10 ft. Often fitted with automobile storing equipment. (CBC)

Automobile Parts Car - A box car specially fitted (usually with racking) for transportation of automobile parts. (CBC)

Auxiliary Reservoir - A reservoir for storage of a supply of compressed air to operate the brakes of each individual car, and supplied from the main reservoir on the engine through the brake pipe. (CBC)

Axle - The cylidrical steel shaft on which the car wheels are mounted. The axle not only holds the wheel to gage, but also transmits the load from the journal boxes to the wheels. (CBC)

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"B" End - The end on which the brake shaft is located or the end toward which the brake cylinder piston points. (CBC)

Ballast Car - A car for carrying ballast for repair and construction work, usually of either the flat, gondola or hopper type.

Bell Crank - An L-shaped lever often with the two extremities connected so as to be of a triangular form, for chainging the direction of motion by ninety (90) degrees. (CBC) see photo

Billing Repair Card - The card that, under AAR Interchange Rules, is furnished to the car owner when repair work is performed on a foreign road car. (CBC)

Body (of a Car) - The main or principal part in or on which the load is placed. (CBC)

Body Bolster - The transverse members of the underframe over the trucks that transmit the load carried by the longitudinal sills to the trucks through the center plates. (CBC)

Body Bolster Bottom Cover Plate - The bottom cover plate used on a bolster of the built-up type. (CBC)

Body Bolster Top Cover Plate - The top cover plate used on a body bolster of the built-up type. (CBC)

Body Bolster Web - A plate or casting forming the filling piece between the cover plates of a built-up body bolster. (CBC)

Body Framing - The framework of that part of a car above the underframe, so called to distinguish it from the underframe. It is commonly subdivided into the side, end and roof framing. (CBC)

Bolster - A cross member on the underside of a car body and in the center of a truck, through which the weight is transmitted. The bolsters carry the body and truck center plates, the body bolster resting on the truck bolster. Truck bolsters are either swing bolsters, admitting of lateral motion, or rigid bolsters, which permit no lateral motion. (CBC)

Box Car - A car with sides enclosed and having a roof; doors are placed in the sides or sides and ends. Used for general service and especially for lading that must be protected from the weather. (CBC)

Box Car Door - Used on both the sides of box cars and sometimes the ends of automobile cars. (CBC)

Brake or Brake Gear - The whole combination of parts by which the motion of a car or train is retarded or arrested. (CBC)

Brake Adjuster - A device for adjusting the slack in foundation brake rigging to compensate for brake shoe wear. (CBC)

Brake Balancer - A modification in the foundation brake rigging whereby the top of the dead lever is connected to the car body instead of to the truck bolster. The object of the device is to relieve the truck of unbalanced stress. (CBC)

Brake Beam - The immediate supporting structure for the two brake heads and two brake shoes acting upon any given pair of wheels. In freight service the practically universal type id of truss construction consisting primarily of tension and compression members fastened at the ends and separated at the middle by a strut or fulcrum to which the truck brake lever is attached. Brake beams are said to be either inside hung or outside hung, depending upon whether they are in the space between the axles or outside the axles. (CBC)

Brake Beam Strut - A post or distance piece made of forged steel, cast steel or malleable iron, between the tension and compression members of a brake beam. The truck brake lever is attached to it. Also called the brake lever fulcrum. (CBC)

Brake Beam Support - A special type of spring attched to the spring plank or other part of the truck and supporting the brake beam by means of a sliding chair casting which is attached to the brake beam. (CBC)

Brake Chain Connecting Rod - A rod connecting the hand brake chain to one of the brake levers, usually the floating lever or the cylinder lever. (CBC)

Brake Cylinder (Air Brake) - A cast-iron cyliner attached to the body frame or truck frame of a car, containing a piston that is forced outwardly by the compressed air to apply the brakes, and when the air pressure is released is returned to its normal position by a release spring coiled about the piston rod inside the cylinder. For older freight cars [using K-brakes], the brake cylinder and the auxiliary reservoir were usually combined, the reservoir being bolted to one end of the cylinder and forming one of the cylinder heads. The piston rod of the freight brake cylinder is hollow and loosely encloses a push rod, which is attached to the cylinder lever. (CBC)

Brake Hanger - A link or bar by which brake beams and attachments are suspended from a truck frame. (CBC)

Brake Lever - A general term designating the levers used as part of the Foundation Brake Gear. (CBC)

Brake Lever Bracket - A general term for any bracket which serves as a fulcrum for a brake lever. The bracket may be integral with, or attached to either the car underframe or the truck frame, or bolster. (CBC)

Brake Lever Connection - A rod connecting two brake levers. (CBC)

Brake Pin - A cylindrical, headed short bar or bolt used to fasten brake rods, levers, etc., together. (CBC)

Brake Pipe - That section of the air brake piping of a car, which acts as a supply pipe for the reservoirs. The pipe is usually 1-1/4" in inner diameter, extends from one end of the car to the other, and at the ends flexible hoses provide connections between cars. When a train is assembled and all brake pipes on the cars are joined, the entire pipe line comprises what is commonly called the "train line." (CBC)

Brake Ratchet (Plain Hand Brake) - A wheel attached to the brake shaft, having teeth which the pawl engages, preventing the wheel and shaft from turning backward. (CBC)

Brake Shaft - The shaft of the plain hand brake, usually vertical and having a hand wheel, handle or ratchet on one end by which a chain connected to the brake levers may be wound on the shaft and the brakes consequently applied. (CBC)

Brake Shaft Bracket - A support for holding the brake shaft in place. (CBC)

Brake Shaft Chain - A chain connecting the brake shaft with the brake levers through the brake shaft connecting rods. The force exerted on the shaft is transmitted by this chain. (CBC)

Brake Shoe - The frictional element that is held against the car wheel in order to produce braking action. (CBC)

Brake Slack Adjusters - A device to take up any slack in the brake gear between the air brake cylinder and the brake shoe, so that the piston travel shall conform to maximum effectiveness of braking. (CBC)

Brake Step - A small shelf or ledge on the end of a freight car, near the top of the end, on which the brakeman stands when applying the hand brake. Sometimes called a brake footboard. (CBC)

Brake Step Bracket - An iron bracket to support the brake step (CBC)

Brake Valve (Air Brakes) - The valve operated to apply and release the brakes. Also called operating valve. (CBC)

Brake Wheel - see Hand Brake Wheel

Branch Pipe (Air Brake) - A pipe extending from the brake pipe to the triple valve in the Type "K" brake, from the brake pipe to the "AB" valve in the "AB" equipment. (CBC)

Branch Pipe Strainer - A dirt collector used in the branch pipe. (CBC)

Bulkhead (Refrigerator Car) - A partition that separates the ice chamber from the part of the car in which the lading is placed. (CBC)

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Cabin Car - A term sometimes applied to Cabooses, but more particularly to the four-wheeled type. (CBC)

Caboose - A car that is attached to the rear of freight trains for the accommodation of the conductor and trainmen as office and quarters while in transit, and for carrying various stores, tools, etc., required on freight trains. (CBC)

Capacity - As applied to a freight car, the nominal load in pounds or gallons that the car is designed to carry; also in cubic feet. These figures are stencilled on the car. See Load Limit. (CBC)

Car Dumper - A device for unloading quickly from a freight car such bulk materials as coal or grain. After being clamped to the rail the car is then tilted or rolled over to discharge the lading. Standard blocking for cradles of car dumping machines has been adopted by the AAR. (CBC)

Car Mile - The movement of a car one mile. A term used in statistical data (CBC)

Car Replacer - A device for getting a derailed truck back on the track. It usually consists of an inclined plain or a curved surface, by which the wheels are raised when the car is pulled, so that the flange of the outside wheel can ride upon and over the rail. Also called Rerailing Frog. (CBC)

Car Seal - A device to secure freight car doors against opening by making it impossible to do so without destroying the seal. (CBC)

Card Board - A small board, secured to the outside of a freight car, on which are tacked cards giving shipping directions or warning of dangerous lading, etc. (CBC)

Card Rack - A small receptacle on the outside of a freight car to receive cards giving shipping directions. (CBC)

Carline - Framing members which extend across the top of a car from one side to the other, and support the roof. (CBC)

Carmer Cut Lever - An uncoupling lever comprised of a long, flat piece of steel that is connected to the car end sill via a bolt that serves as a pivot point. This type of uncoupling lever was used on the USRA forty and fifty ton box cars and was also standard on most Pennsy equipment during the 'teens and 1920's. see photo

Ceiling - The inside of under surface of the roof or covering of a car. (CBC)

Center Anchor (Tank Car) - An arrangement of plates, which are riveted to the tank and to the center sills at the center of a tank car. These plates anchor the tank to the frame and supplant head blocks and double anchors at the ends. (CBC)

Center Bearing - The place in the center of a truck where the weight of the body rests, the truck bolster center plate. A body center plate attched to the acr body here rests on a truck center plate attached to the truck. The general term center bearing is used to designate the whole arrangement and the functions which it performs, in distinction from side bearing. See Center Plate (CBC)

Center Dump Car - A car that will discharge its entire load between the rails. (CBC)

Center Pin or King Bolt (or King Pin) - A large bolt that passes through the center plates on the body bolster and truck bolster. The trucks turns about the bolt, but the stress is taken by the center plates. (CBC)

Center Plate - One of a pair of two plates that fit one into the other and support the car body on the trucks, allowing them to turn freely under the car. The center pin passes through both, but does not really serve as a pivot. The body center plate, or male center plate is attached to the underside of the body bolster or in cast steel bolsters is made an integral part of the casting. The female or truck center plate is attached to the top side of, or cast integral with, the truck bolster. When the car is tilted, as on a curve, part of the weight is carried on the side bearings. (CBC)

Center Sill - The central longitudinal member of the underframe of a car, which forms the backbone of the underframe and transmits most of the buffing shocks, from one end of the car to the other. (CBC)

Center Sill Cover Plate - A flat plate riveted or welded across steel center sills, either above or below, to give additional strength. (CBC)

Centrifugal Dirt Collector - A device connected in the branch pipe between the brake pipe and distributing valve, or triple valve, and so constructed that due to the combined action of centrifugal force and gravity, all dirt and foreign matter is automatically eliminated from the air flowing through the collector chamber and by means of a plug may be removed without breaking any pipe connections whatsoever. When this device is used, the brake pipe air strainer is omitted. (CBC)

Channel - a rolled steel commercial bar shaped like a trough or channel. Used extensively in steel car construction. (CBC)