ADHESIVE BONDING OF END CLOSURES FOR HIGH STRENGTH AND RELIABILITY IN ROCKET MOTOR CASES

Seventeen sub-scale bonded joint cases of a 5 in. nominal diameter and 18 in. in length were fabri cated and hydrotested. Fifteen of these units exceeded the target bonded joint strength of 3750 psi by an average of 40. The information gained from the sub-scale cases was applied to the fabrication of eight prototype bonded and closure cases of 16 in. nominal diameter and 41 inch. length. To assure failure of the bonded joint rather than the case wall, desirable for this program to permit direct examination of the bond line, the bonded joint length was decreased from the original 4 in. length used on the first five cases fabricated. Following the design change, prototype case number eight achieved the 3750 psi target joint strength.