Patent ID: 8206526

Claim:
A process for controlling the formation of wrinkles in a closed cross-sectional, composite laminated structure during manufacturing that cures by heat and compaction, comprising the following steps: a. selecting a closed cross-sectional, composite laminated structure to be made by curing using heat and compaction b. selecting a male tool configured for manufacturing said composite laminated structure; c. selecting a plurality of depression forming elements each used to form a depression in a ply layer of said composite laminated structure; d. laying up a stack of plies made of composite material around said male tool to form said cross-sectional composite laminated structure selected in step a; e. selecting a segment of an outside ply layer to create a depression in said ply layer of said composite laminated structure; f. determining the theoretical length (Lj) of a segment on said outside ply layer and determining the linear length of said segment when a depression is formed by said depression forming element (Li); g. determining the perimeter length of the lay-up composite laminated structure prior to curing (OPL); h. determining the perimeter length of the lay-up composite laminated structure after curing (OPC); i. determining the total number of depression (N) forming elements to be used on the said outside ply using the following equation N=(OPL−OPC)÷(Li−Lj); j. positioning said (N) number of depression forming elements on said outside ply and around said composite laminated structure prior to cure; k. laying up a stack of plies made of composite material around said male tool and around said depression forming elements to form a desired closed cross-sectional composite laminated structure; and, l. curing said lay-up composite-laminated structure using heat and compaction.