Design Changes and Verification

Write about wall thickness and fillets. Include pressure calc. An FEA would be neat

With respect to the HEI used in the staging demonstrator, we increased the wall thickness and added a fillet between the base and the wall.

To calculate the MoS we use an ID of 1.375 in, an OD of 1.842 in, and the maximum pressure of the Sustainer with 826 psi.

Mathinline

body	\sigma_H = \frac{Pr}{t} = \frac{(826 psi)\frac{1.375 in}{2}}{\frac{1.842in-1.375in}{2}} = 2432.01 psi

6061-T6 Aluminum has a yield stress of 40000 psi.

Mathinline

body	MoS = \frac{40000 psi}{2432.01 psi} -1 = 15.4

Thus, the margin of safety is much more than the required minimum of one, which makes us confident that the wall will not yield.

Nevertheless, we would not decrease the wall thickness since we want to avoid radial tore of the bolts.

We changed to 230 and 229 O rings. Verify all O rings including 121 and 122

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No Change, show open motor curve and talk about funny canted nozzles

verify bolt calculations

Manufacturing

include drawings of all parts, where we get them from, and how to machine it

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