Lid deflection

Maintaining compression on a PIP seal between bolts, against a 0.12 mm maximum allowable deflection at seal and enclosure LMC. ANSYS static structural, 1.6 mm aluminium, 3.5 N/mm along the seal track, fixed supports under a 9 mm bolt head.

Eight bolts, not five

Going to eight bolts per side brings deflection between bolts to 0.06 mm, comfortably inside the 0.12 mm limit, with peak stress of 120 MPa under the bolt heads against a 275 MPa yield. A near order-of-magnitude change from three extra fasteners a side.

Lift ear safety factor

Two lift ears in AL 6061 for hoisting the DC-DC assembly during manufacturing install, loaded with a 35 kg distributed mass under gravity. Peak stress 92.5 MPa — a factor of safety of 3.