Matte Tapping Operation 79
The tap holes are sealed with a clay plug which allows the material within the tapping hole to harden. Consequently the hardened material must be burned out to allow molten material inside the furnace to flow out the tapping hole into the launder. The procedure of opening and closing drain holes on the furnace is called "tapping" and is used to maintain proper furnace bath levels. Matte tapping procedures happen, on average, 3 to 4 or more time during a 12 hour shift.