By KEVIN NEVERS

Seven employees at the Burns Harbor facility of Mittal Steel USA were injured this morning, at least two of them seriously, after being burned by molten steel “squished” from the No. 1 vessel at the basic oxygen furnace.

Paul Gipson, president of United Steelworkers Local 6787, identified the two most seriously injured as salaried workers with more than 30 years of service. Both were airlifted to hospitals in Chicago.

All seven employees were wearing required safety gear, including flame retardant clothing, Gipson said, and most of the injuries were to the hands, neck, and face.

The Chesterton Tribune is withholding the names of the injured until assured that their families have been notified.

The incident occurred around mid-morning, as the No.1 vessel was being tapped, and appears to have been caused not by an explosion but by a chemical or metallurgical reaction yet to be identified which “squished” or forced a quantity of the molten steel from the vessel.

That steel hit a protective barrier wall and then back-splashed onto the seven men as they were standing near the No. 1 vessel.

The squishing was preceded by what is called a “foaming action” inside the vessel, caused when the molten steel exceeds the ideal temperature of 3,010 degrees Fahrenheit.

Shortly before the incident, Gipson said, the temperature of the steel had reached 3,200 degrees, causing the foaming action and creating an “unstable” condition.

The foaming action is not in itself unusual, Gipson noted, and is rectified by reducing the temperature to 3,010 degrees by the addition of a standard recipe of 5,000 pounds of burnt lime and 3,500 pounds of “fines,” a powdery substance whose precise composition Gipson was unable to explain.

The vessel operator did in fact add that standard recipe to the No. 1 vessel, Gipson said, and the vessel was being tipped to tap, or empty, when the squishing occurred.

To his knowledge only three things would cause the squishing, Gipson said: an unknown foreign object might have fallen into the vessel; a piece of refractory might have come loose inside the vessel; or the “fines”–which he said were new and being “experimented” with–might have been contaminated or simply unsuitable for the procedure.

Gipson did say the first suspicion–that water might somehow have mixed with the molten steel–was quickly allayed, as no leaks were found in the vessel.

An investigation into the incident has already begun, Gipson said, and the No. 1 vessel will have to be emptied for whatever evidence of the squishing remains.

Gipson did say that new, “much better,” flame retardant clothing called “silvers” are in the process of being issued to employees.

Posted 8/28/2007