A U.S. shipbuilding boom beginning in 1880 encouraged many American shipyards to upgrade their facilities,Heinrich, pp. 81–84. and John Roach & Sons was no exception. In 1880, Roach expanded the facilities of the Chester Rolling Mill by adding a new blast furnace. The new furnace eventually allowed the production of 300 tons of steel weekly, in addition to the 700 tons of pig iron and 300 tons of iron plate the mill was already producing. Roach also added machinery to the mill for the rolling of steel plates.Swann, pp. 151–152.
