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Show 4-1-2. Slab insulation performance The new luminous wall burners were installed in the rear insulating cover of the gas cutter and tested on-line for durability and slab insulation performance, among other characteristics(Photo.1,2). The slab surface temperature was measured by a thermocouple or two-color pyrometer in the luminous edge insulators before and after the gas cutter in Fig.9. The heat transfer coefficient of the slab edges was determined from the temperature measurements. The heat transfer coefficient of the luminous edge insulators is about 10 kcal/mzh t ( 12W/mz . 10, about one-sixth to one-eighth of that of conventional insulating covers or cutting zones. The luminous edge insulators are thus very effective in preventing the temperature drop of cu t slabs and eliminating the temperature difference along the length of cut slabs, as shown in Fig.10. 1200 U 1150 t.al .B 1100 III ~ 1050 E : 1000 u ~ :::I 950 (J) ---_ ... ,\ '. /: Side IUlI,ce unler .. (C,lcul.led) \ ,~ ~~----~ \ , I '", , '( " \ I .. ~ , . (Me ..... d) o 6 10 15 20 25 Time elapsed from machine end (min) Fig.! Temperature profile along the Slab Transportation line -.u '-' Q) L.. .:.J. (Q L.. Q) a ~ _ 1100 ... L- a> C (/J ~ ~1000 E ~ CIJ~ ~ '0 900 ·c ... ~~ :.0..2. . 5..;. BOO ~ .c ~ Slab Size ~ 250'xll00·xll000'(nvnl 40mm luminous Edge Insulator 113t ~ 700~~~~~~4~5~~6--7L-~B--9~~~~--~ L.. .c r Slab length [m] Fig. 10 Effect of Luminous Edge Insulator 9 |