A PRESSURE VESSEL TEST PROGRAM FOR THE EVALUATION OF ROCKET MOTOR CASE MATERIAL 600424
As part of a continuing program of investigating various materials suitable for solid propellant motor cases, Solar Aircraft Company makes extensive use of small size test vessels. During one phase of the program special consideration was given H-11 type alloy steel and the results of tests on this particular material are presented. The effect of such variables as hardness, test temperature, weld mismatch, improper weld technique, and porosity were examined. For the portion of the program discussed, 78 cylindrical test bottles, 6 inches in diameter, were pressurized to burst. Strain gage, volume yield and other types of instrumentation were employed.
The results are presented in terms of the intentional variables and such possible non-intentional defects as minute cracks. Burst test results are compared with data from tests of flat tensile specimens processed with the pressure vessels. Correlation is obtained up to about 265,000 psi ultimate tensile strength; above this level, scatter in burst strength is apparent.