MIL-HDBK-304C Package Cushioning Design Handbook PDF Download (EN)

Inch-Pound MIL-HDBK-304C 1 June 1997 SUPERSEDING MIL-HDBK-304B 31 October 1978 DEPARTMENT OF DEFENSE HANDBOOK PACKAGE CUSHIONING DESIGN This handbook is for guidance only. Do not cite this document as a requirement. AMSC N/A AREA PACK DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Downloaded from https://www.everyspec.com

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MIL-HDBK-304C FOREWORD 1. This handbook is approved for use by all Departments and Agencies of the Department of Defense (DOD). 2. This handbook is for guidance only. This handbook cannot be cited as a requirement. If it is, the contractor does not have to comply. 3. This document provides basic and fundamental information on cushioning materials and their uses. It will provide valuable information and guidance to engineering and technical personnel concerned with designing cushioning systems and specifying required cushioning for protecting fragile equipment. 4. Military Handbook 304C contains many changes from the last revision. -- This version contains both English and metric units.

-- The sections have been arranged according to a six-step design approach shown in Table III. -- The previous version's Section 5 has been deleted (MIL-C-26861- Ramifications in Cushioning Design). -- Graphical data is now available in electronic format. -- Figures have been moved into the text. -- Equipment photographs have been added. -- This revision reflects the changes to the Cushion Design Computer Program now called "Package Designer". -- This document complies with the DOD Acquisition Reform Initiatives. 5. General requirements, theories, illustrations, example problems, cushioning techniques and testing procedures are presented in Sections 4-10. 6.

The graphical data is available in electronic format from the Air Force Packaging Technology and Engineering Facility for Appendix A (Stress-Strain Curves), Appendix B (Peak Acceleration-Static Stress Curves) and Appendix C (Transmissibility-Frequency Curves). See the appendices for further information. 7. Appendix D contains a bibliography of other documents which are referenced in this handbook. These documents provide an in-depth background to the topics listed in this handbook. Parenthetical numbering, such as (3), (12), etc., placed throughout the text will be used to reference literature in Appendix D. Appendix E contains an index based on key words throughout the document. 8.

Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to Air Force Packaging Technology and Engineering Facility, AFMC LSO/LOP, 5215 Thurlow Street, Wright-Patterson Air Force Base OH 45433-5540 or by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. ii Downloaded from https://www.everyspec.com

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MIL-HDBK-304C CONTENTS PARAGRAPH PAGE Foreword ................................ ii Table of Contents ................................ iii List of Appendices ................................ vi List of Tables ................................ vi List of Figures ................................ vii Unit Abbreviations and Metric Equivalents ................................ ix 1.0 Introduction ................................ 1 1.1 Purpose ................................ 1 1.2 Scope ................................ 1 1.3 Objective ................................ 1 2.0 Applicable Documents ................................ 3 2.1 General ................................

3 2.2 Government documents ................................ 3 2.2.1 Specifications, standards, and handbooks ................................ 3 2.3 Non-Government standards and other publications ................................ 4 2.3.1 Other Publications ................................ 4 2.4 Order of Precedence ................................ 5 3.0 Definitions ................................ 6 3.1 through 3.72 -- Definitions ................................ 6 4.0 Define Environments ................................ 10 4.1 Introduction ................................ 10 4.2 Rough Handling Considerations ................................

10 4.3 Levels of Protection ................................ 10 4.3.1 Level A ................................ 10 4.3.2 Level B ................................ 10 4.4 Shock ................................ 10 4.4.1 Shock Spectrum ................................ 12 4.4.2 Intensity of Shocks ................................ 12 4.4.3 Drop Heights and Handling Effects ................................ 13 4.5 Vibration Caused by Shipment ................................ 14 4.5.1 Railway ................................ 14 4.5.2 Truck ................................ 14 4.5.3 Aircraft ................................ 16 4.5.4 Ship ................................

17 5.0 Determine Item Characteristics ................................ 18 5.1 Cushioning Characteristics ................................ 18 5.2 Item Fragility ................................ 18 5.2.1 Fragility Assessment ................................ 19 5.2.2 Product Improvement Feedback ................................ 21 5.3 Shock Isolation Cush. System ................................ 22 5.3.1 Shock Isolation ................................ 22 5.3.2 Shock Isolation Considerations ................................ 22 iii Downloaded from https://www.everyspec.com

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MIL-HDBK-304C 5.3.3 Shock Background ................................ 22 5.4 Shock Absorption Capability ................................ 24 5.4.1 Peak Accel.-Static Stress Curves ................................ 24 5.4.2 Environmental Effects on Static Stress Curves ................................ 25 5.5 Vibration Isolation Cush. System ................................ 26 5.5.1 Vibration Isolation Considerations ................................ 26 5.5.2 Vibration Background ................................ 26 5.5.3 Vibration Transmissibility ................................ 28 5.5.4 Natural Frequency Calculations ................................ 28 5.5.5 Transmissibility Curve Dev.

................................ 30 5.6 Density ................................ 32 5.7 Cost ................................ 32 5.8 Recoverability (Compression Set) ................................ 34 5.8.1 Static Comp. Force-Displacement ................................ 35 5.8.2 Creep ................................ 36 5.9 Tensile Strength and Flexibility ................................ 37 5.10 Dusting and Fragmentation ................................ 37 5.11 Corrosion Prevention ................................ 37 5.12 Hydrolytic Stability ................................ 38 5.13 Abrasive Qualities ................................

38 5.14 Fungus Resistance ................................ 38 6.0 Application Techniques ................................ 39 6.1 Shock Design Procedure ................................ 39 6.1.1 Make Initial Estimate ................................ 39 6.1.2 Material Identification ................................ 41 6.1.3 Select Cush. Application Method ................................ 41 6.1.4 Check for Buckling ................................ 41 6.2 Vibration Design Procedure ................................ 42 6.2.1 Example ................................ 42 6.3 Cushioning Applic. Techniques ................................ 43 6.3.1 Common Applic.

Techniques ................................ 43 6.3.2 Area Adjustment Techniques ................................ 44 6.4 Application of Dunnage ................................ 49 6.4.1 Filling Voids ................................ 49 6.4.2 Padding Projections ................................ 49 6.5 Misc. Application Techniques ................................ 49 6.5.1 Nesting Items ................................ 49 6.5.2 Disassembly of Lrg, Fragile Items ................................ 49 6.5.3 Abrasion Prevention ................................ 50 6.5.4 Cushioned Bases or Pallets ................................ 50 6.5.5 Foam-in-Place ................................

50 7.0 Cushioning Design Procedures ................................ 52 7.1 Summary ................................ 52 7.2 Comprehensive Sample Problem ................................ 52 7.3 Cushion Design by Computer ................................ 53 7.3.1 Reason for Program ................................ 54 7.3.2 “Package Designer” Ordering Data ................................ 54 7.3.3 Cushion Design Program ................................ 54 iv Downloaded from https://www.everyspec.com

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