Extrusion Stem for Aluminum Extrusion Press

The extrusion stem  transfers the power of the main cylinder onto the billet. The stem must operate without bending and cracking. It works under a high pressure determined by the size of the press and the performed application. Therefore, the centering during the operation must be performed properly.

AISI H13(1.2344) is the most frequent used hot tool steel for the stem. This steel is characterized by very good resistance to hot wear and plastic deformation.

It is necessary that the pressing is applied properly since the stem is under high pressures. An unbalanced pressing may result in cracks and bending of the stem. A variation of the centering may result in serious problems. More attention must be paid in order to avoid breakages. Otherwise, this may harm the press, cause bigger losses during the production.

Maintenance suggestions

• Store the stem carefully. Pay attention to small cracks, impact injuries and cuts. Relief the stress after every machine process. Never weld the stem.
• Control the press centering weekly.
• Control the expansion and crack starts at the stem back. In addition, perform a crack control at every dummy block change.
• Always heat up the stem before production.