TRANSFER OF SILICO MANGANESE LIQUID METAL FROM TAPPING BAY TO PIG CASTING MACHINE GIVES POOR YIELD AND HIGH GENERATION OF REMELTS
ONLY 70% METAL CASTED IN PCM AND REST REMAINING IN THE LADLE AND SOME LOSSES THROUGH SKIMMING
STUDY & ANALYSIS
THE REASONS WERE STUDIED THOROULY FOR POOR METAL YIELD AND HIGH SPECIFIC POWERS AND EXCESS QUANTITIES OF REMELTS GENERATION AS;
NEARLY 40 MINUTES TIME TAKING AFTER TAPPING TILL CASTING
SOON AFTER TAPPED LIQUIED METAL AND SLAG COLLECTED IN TO LADLE SHIFTED BY EOT CRANE TO STATION-1 WHERE SLAG DECANTATION IS DONE MANUALLY THEN SHIFTED TO STATION-2 WHERE MANUAL SKIMMING OF SLAG LYING ON THE SURFACE OF LADLE AND THEN TRANSFERED TO PCM FOR CASTING. THIS ENTIRE PROCESS IN 3 STAGES TAKING MORE TIME OF 40 MINUTES AND LIQUIDUS METAL TEMPERATURE DROPPED BEYOND REQUIRED WHICH CAUSED METAL STARTED SOLIDIGYING AND INTERRUPTING FREE FLUIDITY OF METAL WHICH INTURN LEAD TO METAL DEPOSITING IN THE WALLS OF BOTTOM OF LADLE.
PROPOSED SUGGESTION AND ACTION TAKEN:
TO AVOID THE ABOVE PROBLEM, IT WAS SUGGESTED TO REMOVE LIQUID SLAG AT THE TIME OF TAPPING PROCESS BY IMPLEMENTING SEPERATION SYSTEM .TAP OUT SLAG DIVERTED THROUGH LAUNDER TO GRANULATION PIT AND COLLECT PURE METAL ONLY IN TO LADLE.
THIS PURE METAL IN LADLE CAN BE DIRECTELY SHIFTED TO PCM AND THIS PROCESS TAKES ONLY 10 MINUTES BY WHICH METAL TEMPERATURES FOUND RETAINED IN THE LADLE AND 95% OF METAL CASTED IN THE PCM WITHOUT ANY INTERRUPTION.
YIELD IMPROVED AUTOMATICALLY AND REDUCED REMELTS GENERATION AND SPECIFIC ENERGY CONSUMPTION SIGNIFICANTLY.
THE ABOVE WAS ACHIEVED BY CLOSE MONITORING OF TIME VS TEMPERATURE STUDY.
By MVB Rao Ferro Alloys expert