If the average length of a heat is 40 minutes, and operators check the lining once a day, steelmakers could gain a heat a day, Vehec says. Researchers have been testing the sensor at Bethlehem Steel's Sparrows Point, Md., mill over the past year and a half. The equipment includes an optical unit mounted on a tripod in a fixed position. A computer and hardware are on a rolling cart. When the BOF vessel is turned down, operators use a laser to make the initial measurement, Vehec explains.
Conventional sensors have a rotating scanning head that takes various scans of the vessel.
The APC program wants the sensor to be accurate within 1 inch, which is the capability of current technology. There's a lot of radiant thermal heat from the BOF vessel. When you put sophisticated lasers and computers in that type of environment, they need to be mill worthy. Bethlehem Sparrows Point also is the site for the testing of a sensor to measure the temperature and composition of BOF off-gases. Sandia National Lab is working with AISI on this project.