Black stripe on cleaned and annealed cold rolled coils
October 6, 2021
Q. GETTING BLACK SURFACE IN COLD ROLLED STRIPS / PROCESS ELECTROLYTIC CLEANING THEN ANNEALING
JAGDISH MISHRA - SAMBALPUR ORISSA INDIA ^
A. Hi Jagdish. We don't have much info upon which to hazard a guess yet, but it looks to me like oil/grease was getting onto that one particular area on the strip, and burning on and blackening up during annealing.
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