2 BOARD - 2 WAY
Top platform consisting of (2) longitudinally oriented grating sections (each normally 10" wide) with (2) opposite side access openings in the platform hand railing.

2 BOARD - 4 WAY
Same as 2 board-2 way except with (2) additional opposite end access openings in the platform handrailing.

2236
Refers to the most common metal composition of ball valves, (22) for carbon steel body, (36) for 316 stainless steel ball. Within Union Tank Car a valve built to this combination is also referred to as a "carbon steel" valve, even though the ball is stainless steel.

304, 304L
See 316, 316L for definition.

316, 316L
Common grades of stainless steel. The L suffix denotes a low carbon grade suitable for welding. 316 and 316L are more corrosion resistant than 304 and 304L.

3636
Refers to the all S.S. ball valve construction; Both body and ball being 316 stainless steel

"A" END OF CAR
A term used to identify locations on a car, being the end opposite the "B" end. The term is commonly seen with "L" or "R" to designate either left or right side, i.e. "AL" or "AR." See "B" End of Car.

"A" LEVEL PROTECTION
Refers to tank bottom discontinuity (e.g., bottom valves, sumps, washouts, etc.) shear off protection for any discontinuity extending more than 1" below the tank shell. All new cars are built to "A" level requirements.

AAR
Association of American Railroads, whose freight car responsibilities include safety standards (including design related), maintenance, operations, various forms of compensation for use, servicing and repair, car hire and mileage rates, and car service rules.

AAR 206W
AAR tank car class equivalent to DOT 115A (sandwich car) except radio-scopic examination of inner tank welds is not required, and thus, this car class is not used to transport regulated commodities.

AAR 207A
AAR class for transporting granular commodities that are unloaded using air pressure. Ref., Pressure Flow Car.

AAR 211A
AAR tank car class equivalent to DOT 111A except radioscopic examination of tank welds is not required, and thus, this car class is not used to transport regulated commodities.

AAR FIELD MANUAL
See "Field Manual."

AAR OFFICE MANUAL
See "Office Manual."

AAR TANK CARS
Refers to tanks built to AAR requirements which are not as stringent as DOT requirements.

AAR TANK CAR MANUAL
The AAR's Specification for Tank Cars, Specification M-1002. It is the manual for tank car design, construction, repair, documentation, testing and certifications. Officially called Manual of Standards and Recommended Practices; Section C-Part III, it is an important supplement to the Department of Transportation (DOT) Hazardous Materials Regulations, Title 49 CFR, Parts 170-179. These are included in the AAR Bureau of Explosives Tariff No. BOE-6000-U.

ABD
"See Air Brake Control Valve."

ABDW BRAKE VALVE
"See Air Brake Control Valve."

ABDX
"See Air Brake Control Valve."

ACOUSTIC EMISSION INSPECTION/TEST
A non-destructive test conducted on completed tanks, mainly to detect material and structural defects.

ADAPTER, ROLLER BEARING
A casting that fits between a freight car roller bearing and the truck side frame to transfer the load from the side frame to the bearing. See Roller Bearing Adapter.

AEI (AUTOMATIC EQUIPMENT IDENTIF.)
An automatic car scanning system used to assist railroads in tracing and tracking individual railcars. The system requires a transponder be mounted on diagonally opposite corners of each railcar.

AIR ARC
A metal cutting (or removal) process.

AIR BRAKE
Refers to the automatic air brake system used on freight cars.

AIR BRAKE CONTROL VALVE
A complex, pressure-regulating valve installed on each car that applies and releases the brakes and controls charging of the car reservoir. ABD type was required for new cars until 1976, now only allowed as replacement in kind. ABDW was required for new cars from 1977-1992, now only allowed as replacement in kind. Now all new and rebuilt cars must be equipped with stabilized valves such as ABDX; DB-60.

AIR BRAKE HOSE
The flexible hose at each end of a car which is fastened to the brake pipe angle cock on one end, and has a fitting on the other end which engages with a similar coupling on an adjoining car. Sometimes known simply as "the air hose," or the "brake hose." See Trainline.

AIR PIPE (AIR BRAKE)
More properly known as the brake pipe, and often called the "train line."

AIR VALVE
A valve mounted on top of a tank car through which air pressure (or other gas pressure) is introduced to facilitate unloading.

ALKYD
Refers to a paint whose major component is alkyd resin.

ALLOY STEEL
A steel with differing amounts of various elements added to enhance corrosion resistance, or strength, or low temperature resistance, or any combination of properties. Stainless steel falls under this classification.

ALTERATION
A change in tank or fittings that does not change the specification or class, but which does change the certificate of construction.

ALUMINUM
An approved (but seldom used) metal for constructing tank car tanks. Aluminum tanks are built at our Oakville Plant.

AMERICAN RAILWAY CAR INSTITUTE
See "ARCI."

ANGLE COCK
The train air line shutoff valve mounted at each end of a freight car.

ANGLE VALVE
A shutoff valve whose flow path direction generally changes 90 degrees between its inlet and its outlet.

APPLICATION FOR APPROVAL
The upper portion of form AAR 4-2. This required form is submitted to the AAR (normally by the car builder) for all new tank cars and for conversions. Relevant drawings accompany the submission. Once the car design is approved, the application is signed and returned to the car builder. See "Certificate of Construction."

APPROPRIATION NUMBER
A unique Union Tank Car assigned number with a dual purpose: granting authority to spend monies, and a means for tracking that spending.

ARBITRATION COMMITTEE
A standing committee of the AAR Mechanical Division whose duty it is to settle disputes arising between the members under the Rules of Interchange and to recommend changes, amendments or additions to the Rules of Interchange as may be thought advisable from the experiences of the preceding years.

ARC WELD
Any one of a group of welding processes that utilizes the heat produced by an arc or arcs with or without the use of a filler metal.

ARCI
"American Railway Car Institute" an organization that collects and supplies information of value and promotes the common interests of it members who are engaged in the manufacture, design, and/or marketing of rail cars.

ASSOCIATION OF AMERICAN RAILROADS
See "AAR."

ARTICULATED CAR
A car created by joining two or more units to form a single unit with semi-permanent connecting joint(s).

AS CAST
Refers to a metal casting or cast surface that has not received any finishing or treatment after casting.

ASSEMBLE
Means to construct a tank car without welding on the tank car tank. The tank would, in this situation, have been fabricated by another shop authorized to construct tanks.

AUTO RACK CAR
A flatcar with fixed steel racks, for transporting set-up automobiles. Racks have either two or three levels, and are equipped with tie-down devices. Auto rack cars carry an AAR mechanical designation of "FA."

AUTOMATIC EQUIPMENT IDENTIFICATION (AEI)
An automatic car scanning system used to assist railroads in tracing and tracking individual railcars. The system requires transponders mounted on diagonally opposite corners of each railcar.

AUXILIARY RESERVOIR
A part of the air brake equipment on each railway car. Compressed air is stored in the auxiliary reservoir and is admitted to the brake cylinder to apply train brakes when brake pipe pressure is reduced. The auxiliary reservoir is isolated from the emergency reservoir by a separator plate bolted between the halves of the large reservoir tank on each car.

AXLE
The steel shaft on which the car wheels are mounted. The axle holds the wheels to gage and transmits the load from the journal bearings to the wheels. See Black Collar Axle and Raised Wheel Seat Axle.