Question

Write the two properties of an open hearth furnace.

Answer 1

Hint: “Open hearth furnaces are one of a number of kinds of furnace where excess amounts of carbon and other impurities are burnt out of pig iron to produce steel”.
Pig iron means it is produced by smelting ilmenite in electric furnaces.
Complete answer:
The open-hearth furnace, also called OHF, uses the heat produced from combustion of gaseous or liquid fuels to transform a charge of scrap and liquid blast-furnace iron into liquid steel.
The high flame temperature in OHF, required for melting is obtained by the combustion air and, at times, the fuel gas.
The composition of steel can be controlled in an open-hearth furnace.
The quality of steel is very high which is produced by an open-hearth furnace.
Additional information:
The open hearth furnace was developed by a German engineer “Carl Wilhelm Siemens” to prepare steel.
Most of the open hearth furnaces were closed by the early 1990s. Because of their slow operation, and are being replaced by the basic oxygen furnace (BOF) or electric arc furnace (EAF).
The open-hearth process is far slower than that of the Bessemer converter. Thus it is easier to control and to take the sample for quality assessment of steel.
Note: Don’t be confused with the words open hearth furnace and Bessemer process.
The Bessemer process is the first low-cost industrial process for the production of huge amounts of steel from molten pig iron before the improvement of the open hearth furnace.