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					                         PACKING AND CONTAINERS

A. STEPS IN THE MILITARY PRESERVATION, PACKAGING & PACKING CYCLE
    Preservation and unit protection consists of cleaning, drying, preservative application,
     wrap, cushioning, unit packing and identification
    Packing includes consolidation of unit packs or placement of a single item into an
     exterior shipping container with cushioning, blocking and bracing as needed, and
     weatherproofing, strapping and exterior container identification

B. PACKING LEVELS
    Level A—Protection required to meet the most severe conditions known or anticipated
     during shipment, handling, and storage. Used for worldwide shipment and long-term
     storage under possible adverse conditions. A wood box, crate or plastic reusable
     shipping container is generally required as the shipping container for Level A packing.
    Level B—Protection required to meet moderate shipping, handling, and storage
     conditions. Used for worldwide shipments of material not directly exposed to extremes
     of climate and for anticipated storage in favorable warehouse conditions. Weather-
     resistant fiberboard boxes or domestic wood boxes are the minimum required shipping
     containers for Level B packing.
    Minimum protection—Non-military packing level describing protection required for
     known favorable shipping conditions, with limited handling and short-term storage.
     Sufficient protection is required to insure material arrives safely at destination and can be
     stored in favorable warehouse conditions.

C. FIBERBOARD CONTAINERS
   1. Specifications
       ASTM D 4727—Corrugated and Solid Fiberboard Sheet Stock (Container Grade) and
         Cut Shapes is the current specification for the fiberboard material used to make boxes
       ASTM D 5118—Fabrication of Fiberboard Shipping Boxes, replaces PPP-B-636
       ASTM D 1974—Methods of Closing, Sealing, and Reinforcing Fiberboard Shipping
         Containers
       ASTM D 5168—Fabrication and Closure of Triple Wall Corrugated Fiberboard
         Containers, replaces PPP-B-640
       ASTM D 5486—Pressure-Sensitive Tape for Packaging, Box Closure, and Sealing,
         replaces PPP-T-60 and PPP-T-76

   2. Fiberboard Box Classification
       Available in two types—(CF) corrugated fiberboard and (SF) solid fiberboard
       Corrugated boxes are available in three varieties—single-wall (SW), double-wall
          (DW), and triple-wall (TW)
       Boxes come in three classes which describe the ability to withstand moisture:
                    a. Class 1, domestic, with standard moisture resistance
                    b. Class 2, weather-resistant
                    c. Class 3, water and water-vapor resistant (only class 1 and class 2 are
                        used for military applications)
3. Fiberboard Box Styles
    Box style describes how the body, flaps or cover are constructed and joined
    The most common style is the regular slotted carton (RSC) where the top and bottom
       flaps meet in the center when closed
    The full telescoping box (FTC) consists of a body and a snug-fitting cover which
       slides down completely over all sides (similar to a shirt box)
    The one piece folder (OPF) is constructed so that all outer flaps fold around to
       completely enclose the item and is also known as a book wrapper
    Twelve additional styles are described in ASTM D 5118, with drawings of each

4. Grade Designations
    Fiberboard box strength is defined by the grade designation
    The grade describes the bursting strength, or the pounds per square inch required to
      punch a hole in a sheet of the fiberboard (e.g. grade 200, 275, or 350)
    Grade does NOT describe how much weight a box made of the fiberboard will hold
    Examples of weather-resistant grades are V3c, W5c, or V11c
    The table below indicates weight and size limitations of various grades of fiberboard
      boxes. It shows some of the more commonly used grades of boxes. See ASTM D
      5118 for additional grades.


      Gross Weight and Size Limits of Domestic and Weather-Resistant Boxes

                      GROSS WEIGHT OF BOX                     MAXIMUM LENGTH +
    GRADE               AND CONTENTS                           WIDTH + DEPTH

    125                            20 lb.                             40 in.
    200, W5s, W5c                  65 lb.                             75 in.
    275, V3c, V3s                  90 lb.                             90 in.
    350, V13c                     120 lb.                            100 in.

5. Boxmaker’s Certificate
    Generally a circular marking which signifies compliance with the transportation
      freight classification rules of box construction
    Newer specifications permit a rectangular marking indicating compliance with an
      edge crush test
    The certificate indicates the box manufacturer, the strength test met (grade), maximum
      box size, and gross weight limitations
    Domestic class boxes are not required to be marked with an ASTM designation
    Weather-resistant boxes must additionally be marked with the weather-resistant grade,
      date of manufacture (month/year), and “Complies with ASTM D 5118”
D. WOOD BOXES AND CRATES
   1. General Information
     Wood is valuable as a container material because of its strength and availability
     Softwoods come from coniferous trees such as pine or fir
     Hardwoods come from broadleaf trees such as elm, cherry, or oak
     MIL-HDBK-7, Lumber & Allied Products (292 pages) is a good source of information on
      wood, but may not be cited in contracts

   2.   PPP-B-601, Cleated Plywood Box
       Superceded by ASTM D 6251 in February 2001
       Maximum gross weight is 1000 pounds
       Can be constructed for both domestic and overseas classes
       Construction requirements are determined by the specification and are dependent on the
        weight and dimensions of item(s) being packed
       The following minimum requirements are provided as inspection tips
       The plywood construction grade must be C-D or better
       Minimum plywood thickness is 5/16” for the lightest items
       Cleats should not be less than 3/4'” by 1 ¾”
       Intermediate cleats should be perpendicular and not more than 24” apart
       Maximum spacing of nails should not exceed 5 inches
       All boxes with a gross weight over 200 pounds must have at least two skids
       Overseas boxes require thicker cleats, larger nails, drainage apertures, and the use of CD-
        X plywood (plywood made with exterior glue)

  3.    PPP-B-621, Nailed Wood Box
       Specification is inactive for new design
       Can be constructed for both domestic and overseas classes
       Maximum domestic gross weight is 600 pounds
       Maximum overseas gross weight is 1000 pounds
       Construction requirements are determined by the specification and are dependent on the
        weight and dimensions of item(s) being packed
       The following minimum requirements are provided as inspection tips
       No knots in boards are permitted greater than 1/3 the board width or 4”, whichever is less
       Minimum board thickness is ¼” for hardwood and 3/8” for softwood
       Regular spacing of nails should not generally exceed three inches
       Skids are required for boxes over 200 pounds gross weight

  4. MIL-B-26195, Wood Cleated, Skidded, Load Bearing Base Box
     Superceded by ASTM D 6256
     Maximum load weight not to exceed 2500 pounds or 16 feet in length
     Intended that the entire load be carried on the base of the container
     The superstructure, fabricated according to PPP-B-601 or PPP-B-621, is designed as
      protection from the elements and for stacking purposes
    The thickness and number of load bearing floorboards are determined by the item weight
      and specified by the load chart in the specification
        Load bearing members over two inches thick must be fastened to the base with 3/8”
         carriage bolts
        The superstructure is fastened to the base with lag bolts for ease in disassembly

   5.   MIL-C-104, Sheathed Wood Crate
        The specification is inactive for new design
        Intended for loads up to 30,000 pounds
        Constructed in two types—nailed or bolted
        May be class 1, lumber sheathed, or class 2, plywood sheathed
        May be fabricated with a skid base or a sill base (like a reinforced framework)
        Bases should have half-inch drainage holes drilled into plywood flooring
        Include ventilating holes or slots drilled at a 45 degree angle to drain outward

E. REUSABLE CUSHIONED CONTAINERS
   1. Short-life containers designed by the Air Force (fast packs), which are weather-resistant
   boxes made with polyurethane foam bonded to the inside of the container
       Type I (MIL-STD-2073 container code NR) Vertical Star Pack, along with Type III
          and IV, used for electronic equipments such as power supplies, receiver-transmitter
          units, and other repairable equipment
       Type II (code NS) folding convoluted foam container used mostly for circuit cards
       Type III (code NV) telescoping box
       Type IV (code NW) Horizontal Star Pack

   2. Long-life containers designed by the Navy and Air Force are made of plastic with
    various cushioning, shock mounts or suspension systems
         Type VI (code NY) plastic, molded clamshell container with convoluted foam
           cushioning used for circuit cards and other flat items
         Type VII (code NZ) large plastic containers with polyurethane cushioning which
           forms a cavity, used to ship medium and large repairable items
         Type VIII (code MY) plastic container with a coiled steel cable shock mounted
           platform, used to ship very fragile components such as altimeters, inertial navigation
           units and gyroscopes
         Type IX (code WY) similar to Type VIII with elastomeric shock mounts
         Type X (code RC) similar to Type IX

F. PACKING REQUIREMENTS OF MIL-STD-2073-1D, APPENDIX C
    SCOPE: Appendix C provides general requirements for containers
    The document section provides a list of all military, federal and commercial container
     specifications cited in MIL-STD-2073-1D. Addresses are included to obtain copies
    General requirements
        o The size of the container selected should not be too large for the item being
             packaged. The item and necessary cushioning should fill at least 80% of the
             container volume. Dunnage may be used to fill the remaining volume
        o Unit containers may serve as shipping containers if they meet the packing level
             specified in the contract
   Table C.I. lists specifications for various interior containers (bags, boxes, sacks, etc.)
   Table C.II lists exterior shipping containers which can be selected by the weight of the
    contents and the Packing Level specified. Note the ASTM containers are shown at the
    end of the table.
   Table C.III lists standard sizes and National Stock Numbers of class weather-resistant
    fiberboard boxes which are stocked by GSA
   Table C.IV lists all the military reusable containers by NSN, contents weight and
    dimensions, and outside container dimensions

				
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