Mixed Loads.

TM 38-400/NAVSUP PUB 572/AFMAN 23-210 MCO 4450.14/DLAM 4145.12

and section 2 of "Loading Rules for Open Top Cars.")

(4) Segregation by units. When separating

containers by units lengthwise of the car, the

3-71. Mixed Loads.

recommended loading pattern for the different

a. Nature of problems. The variety of different

containers as covered in the AAR pamphlets for solid

shapes, sizes, and weights of articles and containers, so

loads of the containers should be followed (i.e.,

frequently required to be loaded together in one car,

fiberboard boxes in bonded block patterns, cylindrical-

furnishes a greater problem than solid loads of one type

type containers by nesting or offsetting, and bagged

container or commodity. It is paramount that the

commodities by brick wall or binding methods).

number of mixed cars be held to a minimum. Planning

c. Separation gates. Generally, separation gates

the shipments to obtain the maximum of solid loads will

are required when containers of different type and size

not only result in less damage, but will prove to be more

are loaded side by side. Separation gates may be of the

economical in bracing material and loading time

floating type (not secured to the car sidewalls) when

required. (See AAR pamphlets 4, 13, and 18 for

used between units of containers having practically the

additional information.)

same strength and rigidity. When separation gates are

b. Segregation of load.

used between a unit of heavy strong containers on one

side and a unit of lighter and weaker containers on the

(1) Scheduling for segregation. The same

other side, the separation gate should be fastened in

type containers or articles in a mixed load should be

place to prevent the heavier containers crushing the

loaded together in the car; the loading and bracing

lighter containers when subjected to load pressures.

practices should be followed as for solid loads of these

When the load pressure exerted in either direction may

individual items. More efficient working procedures are

cause damage, the separation gate should be anchored

obtained when it is possible to schedule flow of supplies

in both directions by the reverse steel strap method.

to the loading platform in order to be segregated.

See AAR pamphlet 14 for detailed information

(2) Methods of segregation. The following

concerning the construction of separation gates. In

methods of segregation are suggested by

addition, AAR bulletin 527 of the General Information

(a) Layer.

Series contains information on the construction of a

(b) Units lengthwise of the car.

reusable car brace for securing part car loads. This

brace is adaptable for use when switching cars on the

station during the loading of mixed shipments. Certain

(3) Segregation by layer. When segregating

types of special box cars have built-in fixtures and

or separating articles by layers, the heavy articles

equipment for quick application of multipledeck flooring,

should be in the lower layers; the lighter and fragile

adjustable gates, bulkheads, etc.

These cars are

items in the upper layers. For example, drums, barrels,

particularly adaptable to the securement of delicate or

heavy crates, or boxes in the floor layers; bagged

fragile freight.

commodities, wirebound boxes, and fiberboard boxes

should be loaded on top of the heavy containers. If the

d. Blocking. Machinery and rough items such as

lighter containers or items cannot be loaded directly on

castings, steel frames, pipes, and bars should be

top of heavier containers, separators or fillers will be

blocked lengthwise and crosswise in the car as

placed between the layers. These separators may be of

recommended for these commodities in the applicable

wood or fiberboard, depending on the amount of

AAR pamphlets.

protection or support required.

When loading

e. Separators. Separators will be used when one

commodities in bags or fiberboard containers or lightly

side of the car contains items or containers that may be

constructed wood boxes on top of barrels or drums,

crushed because of lateral pressures caused by side

wood filler boards will be used as separating medium;

shift of heavier articles.

The separators will be

when separating bags loaded on fiberboard containers,

reinforced by blocking to car floors and sidewalls.

heavy paper will suffice. Generally, separators are not

Where the containers loaded adjacent to each other

required between layers of the same type of wood

need protection only from tearing, snagging, or chafing,

boxes, wirebound boxes, and fiberboard containers;

it will be not be necessary to secure the separators in a

however, small dimension containers will not be loaded

fixed position. The separators will be placed lengthwise

directly on or against unsupported panels or cleated

in the car between the two different type containers (i.e.,

panel containers or open crates without adequate

when open crates are loaded adjacent to fiberboard

separating material.

containers). The fillers or separators serve the sin-

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