Definition of open-hearth in US English:



  • Denoting a steelmaking process in which the charge is laid on a hearth in a shallow furnace and heated by burning gas.

    • ‘After that would come the open-hearth furnaces, but they'd require a better supply of pig iron and a new building in which to build them.’
    • ‘In the following years he reinvested profits to renovate the plants, raised additional money through bond issues, and replaced outdated open-hearth furnaces with modern production technologies.’
    • ‘The manufacture of steel was made possible by two new inventions, the Bessemer converter of 1856 and the Siemens-Martin open-hearth furnace of 1864.’
    • ‘The 138-acre site housed a recycle mill with open-hearth furnaces from the early days of the 20th Century.’
    • ‘A plaque placed beside the mural, Spirit of Steel, notes that the scene depicts the entire steel manufacturing process, from the mining of coal and ore to the making of steel in open-hearth furnaces, to the finished steel shaft.’
    • ‘He also contributed to metallurgy, working with Sir William Siemens on the development of the open-hearth steel furnace, and with Henri Sainte-Claire Deville on the extraction of aluminium.’
    • ‘Less trouble is experienced with acid open-hearth steel (usually containing 4 cc per 100 gm) than with basic electric steel containing about 6-8 cc per 100 gm of hydrogen in the ladle.’
    • ‘Misa's account of the skyscraper is a bit more complex and provides crucial details of how designers and builders came to favor open-hearth steel over steel produced by Bessemer rail shops.’
    • ‘Ispat Karmet produces 5.2 million tonnes, a little less than the Soviet peak because the open-hearth plant was shut down for environmental reasons, say company officials.’
    • ‘The minimum overheating temperature depends on the ‘purity’ of the steel and is substantially lower in general for electric steel than for open-hearth steel.’
    • ‘The Bessemer process and its successor, the open-hearth method, underlay a second industrial revolution that transformed the United States into the world's premier industrial and military power.’
    • ‘Coreless and channel induction furnaces, crucible and open-hearth reverberatory furnaces fired by natural gas or fuel oil, and electric resistance and electric radiation furnaces are all in routine use.’