The year 1947 marked the peak production at the Navy Yard Annex. With the close of World War II, the Navy Yard activities had shifted from ship building to the manufacture of explosives, ammunition, and small arms. The Annex was the nerve center for Navy Yard ordnance production, creating standardized plans for private industries, repairing damaged equipment, and producing specialized prototypes not only for the Bureau of Ordnance but also for almost every other government agency and many private companies as well.
In this photo, a foundryman pours molten for conversion to steel at the Steel Foundry, Building 137 (no longer extant). The Steel Foundry was located just west of the Boiler House and Power Plant.