REXALLOY®™ die inserts are usually furnished ground on O.D. and two faces. The die holder can be made from Halcomb 118 bar stock or forgings, and should be about 50% thicker than the insert. The holder should be drilled with the hole slightly larger than the extruded bar size, and then counterbored to a depth slightly greater than the thickness of the insert, and to a diameter .008”/.010” less than the diameter of the insert. Larger inserts, greater than 2.000″ O.D. I, may require .010″/.015″ shrinkage. The die holder should be hardened to about 40 -HRC.

REXALLOY®™ is a proprietary trademark of Alloy Cast Products, Inc. (73779483) U.S.A

After the insert is finished and polished the I.D., shrinking into the holder is then accomplished by heating the holder to about 400/500 degrees Fahrenheit, and then preferably cooling the insert in dry ice. A pin gauge a few thousandths longer than the diameter of the insert, when cold, can be used to check the counterbore of the heated die for size before dropping the insert into the die holder. It is important that the REXALLOY®™ insert be under compression so that there will be a tendency to close up any heat checks which usually form on the inside surfaces in the first or second extrusion pass.

REXALLOY®™ is a proprietary trademark of Alloy Cast Products, Inc. (73779483) U.S.A

The dies should be preheated slowly to a temperature of at least 700-800 degrees Fahrenheit before the first extrusion. It is important that wide temperature fluctuations be avoided, otherwise heat checking will be extensive, and flake-out may occur. Thus cooling between pushes is unnecessary, and after the last push, the dies should be slowly cooled in air to room temperature. DO NOT WATER JACKET COOL.

REXALLOY®™ dies should be swabbed with a graphite-base lubricant before each extrusion.

REXALLOY®™ is a proprietary trademark of Alloy Cast Products, Inc. (73779483) U.S.A

REXALLOY®™ dies are overhauled when necessary by belt-polishing with a fine grit abrasive belt, or die grinder with a fine stone. REXALLOY®™ dies hold their size exceptionally well because of their high hardness at elevated temperatures, (see details on DATA SHEET), and the fact that REXALLOY®™ is unaffected by any heat treatment, and cannot be tempered or annealed.

REXALLOY®™ is a proprietary trademark of Alloy Cast Products, Inc. (73779483) U.S.A

We recommend the following abrasive wheels for grinding REXALLOY®™

• For Cylindrical Grinding – W-46-JB
• For Surface Grinding – W-46-HB1

REXALLOY®™ is a proprietary trademark of Alloy Cast Products, Inc. (73779483) U.S.A