TM 55-203
Section III. REFRIGERATOR CARS
9-17. Insulation
9-15. General
The framework of a refrigerator car is similar to that of a
Insulation is provided by materials of required thermal
boxcar, with special facilities to provide and maintain
conductivity. It should be in blanket form, with a
temperatures at a desired level. Refrigerator cars are
suitable backing and should be applied to car sides and
used to transport perishable commodities or other items
ends in continuous blankets extending from the doorpost
dependent upon refrigeration or heat to prevent their
around the end of the car to the opposite doorpost. An
deterioration. These cars employ insulated structures to
insulation blanket will extend the length of the floor and
retain heat or cold as desired. They have thick floors,
another the length of the roof. Insulation should be 3
sides, and roofs, are equipped with ice bunkers or some
inches thick on sides and ends and 3 1/2 inches thick on
form of mechanical heating or refrigeration. A number
floors and roofs. If temperatures in refrigerator cars are
of US Army standard gage, domestic-type, 50-ton
unstable or it becomes difficult to maintain adequately
boxcars have been converted for use as foreign service
low temperatures, an inspection must be made to
ice refrigerator cars.
These cars have welded
determine whether any of the structure has been
underframes, all welded steel sheathed superstructure,
damaged. If the inner and outer walls, roof, doors,
steel ends, rigid galvanized steel roof, sliding doors and
floors, and ends are in good condition, the insulation
ice ,compartments, stationary type, at each end,
must be examined for condition and positioning.
arranged for full or half stage icing These cars have a
Dislocation or disability of the insulating material
capacity of approximately 2,000 cubic feet available for
generally can be detected by differences in temperature
loading. Exterior and interior views of these cars are
of the outer shell of the refrigerator car. At such points,
shown in figures 2-1, 2-2, and 2-3. Discussion herein is
sections of the structure (lining, etc.) will have to be
confined to those features peculiar to any type of
removed to gain access to the insulation in the affected
refrigerator cars which presents the major maintenance
area. If the insulation has only shifted, it will merely
problems. Recently built 40-ton mechanically activated
require relocation and reaffixing. If it has become water
US Army-owned refrigerator cars are operated on
soaked or matted, it must be replaced. This same
certain foreign narrow-gage lines for US forces. These
procedure is followed in repairing the doors and padding
cars are maintained by the 'host national railroads under
around the doors. If the canvas covering the padding
supervision of US Army personnel as discussed in TM
becomes wrinkled or torn through 'use, it should be
55-205. These cars are mounted on conventional type
smoothed or reattached.
trucks, equipped with coil springs and roller bearing
journals. This car is illustrated in figure 2-2.
9-18. Doors
9-16. Flooring
a. General. Doors of refrigerator cars generally
are provided in pairs and located centrally in the side of
Refrigerator car floors usually are constructed of two
the car. They are thick and adequately insulated. The
layers of wood with some type of insulating material
edges of the doors are beveled, matching the bevel of
applied between them and covered with a waterproofing
the door frame. This permits free-swing clearances and
material. The principal problem In the maintenance of
tightness of fit when the door is closed. Some of the
refrigerator car flooring is to keep the structure
difficulties that are encountered in maintaining
waterproof and free from abrasions caused by impacts
refrigerator ,car doors include lack of airtightness and
sustained in loading. If water is permitted to seep
disability of the locking devices.
through the floor, it will adversely affect the insulating
materials, nullifying their efficiency. It also causes the
b. Airtightness. The airtightness of car doors is
insulation to become soggy and matty, promoting
dependent upon the closeness of fit, and the manner in
displacement by sagging. Water seepage can be
which the padding around the door )has been applied. If
arrested only by constant inspection and maintenance.
the padding was loosely applied, permitting it to become
When abraded conditions of the floor covering are found
folded or wrinkled, leaks will develop. Padding can
it must be promptly repaired or replaced. Renewals
become hardened and lumpy, thus contributing to air
must be treated with waterproofing compounds to
leakage. When such conditions are found, defective
prevent leakage.
padding will be replaced. Sprung doors or door
9-8
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