Paper number 187

COST COMPARISONS OF WET FILAMENT WINDING VERSUS PREPREG FILAMENT WINDING FOR TYPE II AND TYPE IV CNG CYLINDERS

Frederick W. DuVall

Thiokol Propulsion from Cordant Technologies, P.O. Box 707, M/S 230
Brigham City, Utah 84302-0707, U.S.A.

Summary

This paper quantifies the significant cost elements for filament winding with wet resins and with pre-impregnated tow fibers. A detailed cost model is presented that calculates the total cost contribution for each winding approach. Two types of over-wrapped cylinders will be studied. Both Type II and Type IV CNG cylinders will be studied to select the most cost-effective approach of either wet winding or prepreg winding. A Type II CNG cylinder is a metal cylinder that is circumferentially wrapped with fiber tow over the straight cylindrical section. A Type IV CNG cylinder is a plastic cylinder that is fully over-wrapped with both circumferential and helical fiber tows. A cost model with the detailed assumptions and data required for making valid cost comparisons between wet and prepreg filament winding will be presented. This model will be useful for making cost comparison for alternate materials and designs and will allow the user to make informed selections that will yield the most cost-effective approaches for typical CNG cylinders.

Keywords

filament winding, compressed natural gas cylinders, wet filament winding, prepreg filament winding, cost comparisons.