A solution was developed to mitigate the potential risk of ignition failures and burn-through in aluminum primer chamber assemblies on pyrovalves. This was accomplished by changing the assembly material from aluminum to steel, and reconfiguration of flame channels to provide more direct paths from initiators to boosters. With the geometric configuration of the channels changed, energy is more efficiently transferred from the initiators to the boosters. With the alloy change to steel, the initiator flame channels do not erode upon firing, eliminating the possibility of burn-through. Flight qualification tests have been successfully passed.
This work was done by Carl S. Guernsey and Masashi Mizukami of Caltech, Zac Zenz of Conax Florida Corp., and Adam A. Pender of Lockheed Martin Corp. for NASA’s Jet Propulsion Laboratory. For more information, contact