The

IPM

GROUP

Farmington Hills, Michigan

Contact usBeni Dror

27003 Hills Tech Drive

Farmington Hills, MI 48331

Tel: 248 489 9490,

Fax: 248 479 0771

e-mail: bdror@ipmworld.com

Web:www.ipmworld.com

Mail Address: P.O.Box 252223

West Bloofield, MI 48325

Tactical Wheeled Vehicle Weight Reduction Initiative

May, 2004By

International Projects Management (I.P.M) LLC

Phone: 248 489 94 90

Preamble

The attached are Examples of an on going weight reduction initiative

for the HUMVEE.

PROGRAM

Selected Components were analyzed to re-engineered to reduction weight by 15%-20%

Brackets, Brackets Supports & Transmission Supports.

Potential

Additional Components Under consideration: Alternator support bracket Chassis beams Engine components

Material and Manufacturing Method Selection

Selecting the most appropriate material and manufacturing methods according to the part loading and stiffness. Special welding processes of high

strength steel sheet More Accurate Casting process to

reduce tolerances

Using FEA methods

Using Finite Element Analysis enables us to refine the stress distribution under more realistic load application and attachment conditions, eliminating the inherent conservatism present in the original calculations. Material lightly loaded can then be safely trimmed from the original part.

Examples of FEA used for weight reduction.

Part No. 12338191- Spring Seat:from 10.9 lbs to 9.4 lbs

Part No. 12469497- Alternator Support:

from 25.3 lbs to 21 lbs Part No. 12469498- Compressor Bracket:

from 9.8 lbs to 8.1 lbs

Stress Report AbstractPart No. 12338191

Compiled

Name: J. HornsteinTitle: Stress Engineer

Checked

Name: J. HornsteinTitle: Stress Engineer

Approved

Name: Dr Fredy H. OrnathTitle: CEO Materials

Systems

1 Subject: Spring Seat, Front, Stress Analysis

2 Scope

The scope of this report is to compare the strength of the proposed-design to the current design of the subject part under the same stipulated set of external loads. Currently the part is a low alloy, steel sheet (Ftu = 60 ksi) welding assembly while the new design is a casting made of ductile iron of higher strength (Ftu = 100 ksi).

3 Abstract

A coarse FEM of the current (welded) part was created and subjected to the stipulated set of applied loads.The internal loads, (reactions at the rail attachment and the part displacements and stresses) were calculated.The geometry of this model was then modified to represent the proposed design, retaining the loading and

reaction system and the internal loads were calculated again.A strength comparison was then performed considering both internal loads and material properties and a safety

factor for the proposed part was calculated when applicable.

4 Conclusions and Recommendations

The maximum calculated stresses in the current part are exceeding the UTS of the material in the attachment flanges, which is attributable to the inherent conservatism of the analysis. On the assumption that the part had passed the certification tests this should not be a matter of concern.

While the strength of the proposed part is exceeding the strength of the current part, because of the material’s low elongation (3% vs. 22% for the current design) it is recommended to eliminate hot spots of tensile stresses above 100000 psi by extending the lower bosses all the way to the horizontal flanges (see Figure 2.1.1 on the next page)

5 References

The contents list of the full stress report, available at materials systems ltd, is given on page 2.1.4.

Current 12338191 – image

Current 12338191 - welding

New 12338191 - casting

12338191 – Welding – FE Model plot

12338191 – Casting – FE Model plot

12338191 – Welding – FE Results plot

12338191 – Casting – FE Stress plot

Part No. 12338191

Stress Report:

Open 12338191_Stress_Report_Abstract.doc

12469497(R) and 12469498(L)

Stress Report AbstractPart No. 12469498

Compiled

Name: J. HornsteinTitle: Stress Engineer

Checked

Name: J. HornsteinTitle: Stress Engineer

Approved

Name: Dr Fredy H. OrnathTitle: CEO Materials

Systems

12469498 – Original part

New Part: Weight reduction accomplished by opening cutouts in original part

12469498 – Original - FEM

12469498 – Redesigned - FEM

Part No. 12469498

Stress ReportOpen

12469498_Stress_Report_Abstract.doc

Note:Aluminium Cast Alloy (e.g. 300 Series Aluminium Cast Alloy, MIL-HDBK-5G chapter 3.9) could offer acceptable strength, while reducing the part weight to a third of the current 9.8 lbs

Stress Report AbstractPart No. 12469497

Compiled

Name: J. HornsteinTitle: Stress Engineer

Checked

Name: J. HornsteinTitle: Stress Engineer

Approved

Name: Dr Fredy H. OrnathTitle: CEO Materials

Systems

12469497 – Redesigned part

Weight reduction accomplished by opening cutouts in original

part

12469497 – Redesigned - FEM

Part No. 12469497

Stress ReportOpen

12469497_Stress_Report_Abstract.doc

Note:Aluminium Cast Alloy (e.g. 300 Series Aluminium Cast Alloy, MIL-HDBK-5G chapter 3.9) could offer acceptable strength, while reducing the part weight to a third of the current 25.3 lbs