A professional who tends equipment that crushes and mixes materials, such as brick, clay, and refractory mud, to form refractory mortar, used to line interior of furnaces. Respnsibilities include:

• Starts crushing machine and shovels materials into hopper.
• Shovels crushed materials into wheelbarrow and dumps materials into hopper of mulling (mixing) machine.
• Turns valve to admit water into mulling machine and starts machine.
• Feels consistency of mixture and adds crushed material or water to obtain mixture of specified consistency.
• Shovels mixture into mud box for transportation to work area.