Near-net shape manufacturing of tank bosses for type IV hydrogen storage tanks

A pressure vessel boss is a metallic component that provides a structurally reinforced connection point for the attachment of valves, fittings, or instrumentation to a pressure vessel. This study investigates alternative manufacturing routes for producing such bosses from the aluminum alloy 6061. The proposed approaches include closed-die forging in the solution heat-treated condition immediately after quenching (W temper), followed by backward can extrusion either in the artificially aged condition (T6) or in the W temper condition with subsequent age hardening. To assess the influence of the age hardening conditions of 6061 on the inner surface, scaled-down backward can extrusion experiments are performed. The near-net-shape forming process offers the advantage of reduced manufacturing time while simultaneously ensuring a defined grain flow direction.

Rakshit, T., Weber, F., Burger, S., Poincelet, D., Korkolis, Y.P., 2025

Comparison of Alternative Manufacturing Routes of Aluminium Bosses Used in Pressure Vessels. 58 Plenary meeting, International Cold Forging Group.