Method and apparatus for hardening mold grids using clamp quenching

A method for treating a workpiece, the method comprising:

• laterally offsetting vertical layers of a plurality of mold grids from one another to form a workpiece;
• moving the workpiece laterally along a conveyor assembly into a furnace for heating in a carbon-rich atmosphere to form a heated workpiece;
• receiving the heated workpiece from the furnace on the conveyor assembly;
• applying clamping pressure to the heated workpiece while the heated workpiece is on the conveyor assembly to form a clamped assembly;
• and
• moving the clamped assembly, including at least a portion of the conveyor assembly, into a quenching bath until the heated workpiece is quenched.

A method for treating a workpiece, the method comprising:

• moving the workpiece laterally along a conveyor assembly into a furnace for heating in a carbon-rich atmosphere to form a heated workpiece, the workpiece of a type comprising a plurality of mold grids arranged in vertical layers;
• interposing permeable grates between each of the mold grids within the workpiece so as to allow quenching fluid to pass through the grates and contact surfaces on adjacent mold grids;
• laterally offsetting the vertical layers from one another so as to enhance the contact of the quenching fluid with top and bottom surfaces of the heated workpiece;
• receiving the heated workpiece from the furnace on the conveyor assembly;
• applying clamping pressure to the heated workpiece while the heated workpiece is on the conveyor assembly to form a clamped assembly;
• and
• moving the clamped assembly, including at least a portion of the conveyor assembly, into a quenching bath until the heated workpiece is quenched.