Hewitt's Furnace — The Steel Bessemer Could Not Make

In the summer of 1867, while the world marveled at the Bessemer converter, American industrialist Abram Stevens Hewitt stood before a different furnace entirely — and recognized the machine that would eventually replace it. The open-hearth furnace, developed by Charles William Siemens and Pierre-Emile Martin, had just won the Grand Prize at the Paris Exposition Universelle, and Hewitt, serving as official American Commissioner for iron and steel, understood exactly what he was seeing.

This episode traces why the open-hearth process ultimately overtook the Bessemer converter as the dominant method of American steelmaking. You will learn how the eight-to-ten-hour heat gave metallurgists something the violent twenty-minute Bessemer blow never could: the ability to sample, adjust, and confirm chemistry before committing a heat. You will learn why nitrogen contamination from the Bessemer air blast was a structural liability, not a theoretical concern, and how it quietly disqualified Bessemer steel from the most demanding applications of the industrial age. And you will learn why the open hearth's ability to charge cold scrap made it not just a better furnace, but a smarter one — positioned to feed on the wreckage of the very infrastructure that the Bessemer process helped build.

Hewitt licensed the Siemens-Martin process and brought metallurgist Frederick J. Slade into the technical work. What followed shaped the steel behind twentieth-century America.

Iron & Engine covers the machines that built America — the engineering behind them, the men who ran them, and what was lost when the knowledge left with the men.

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Attributions:

“Práce na martinské peci.jpg” by Viktor Mácha, licensed under Creative Commons Attribution-Share Alike 4.0 (CC BY-SA 4.0).
https://commons.wikimedia.org/wiki/File:Pr%C3%A1ce_na_martinsk%C3%A9_peci.jpg

“Oxygen injection in open hearth furnace Manual oxygen lance.png” by European Commission and European Coal and Steel Community, licensed under Creative Commons Attribution-Share Alike 4.0 (CC BY-SA 4.0).
https://commons.wikimedia.org/wiki/File:Oxygen_injection_in_open_hearth_furnace_Manual_oxygen_lance.png

Видео Hewitt's Furnace — The Steel Bessemer Could Not Make канала Iron & Engine