February 2021 Volume 3

EQUIPMENT & TECHNOLOGY

Reducing the Cost of Your Forging Process By Terry McInerney

Every day you face the challenge of improving your forging business to remain competitive. You are consistently making decisions that will affect your revenue and profitability. This article is intended to offer specific guidelines to forgers who want to continuously improve. It is intended to spur conversations around tool and die design, and how choices of material, heat treatment, and many other factors will alter the overall cost and efficiency of your operation. Will your choice of punch tooling material and coating impact your output between tool changes? Absolutely. Could a modification to the die design and how it attaches to the bolster drastically affect downtime for changeover? Definitely. Our hope is that you will use this article as a thought starter, an idea generator, a valuable tool to help your company eliminate wasted time, money and other precious resources on your journey to be the best forging company on the planet. Tooling Design Though difficult to define, most people know good designwhen they see it. Good design means things work like they are supposed to, can offer benefits you didn’t even know you desired. In a forging plant, design choices can mean the difference between running profitably and being constantly in the red. Like it or not, design choices relative to tooling and press setup will affect the level of success as a forger.

Material Selection Choosing the right forge tooling material is critical. Over decades of forging, the industry has identified and developed many grades of tool steels, each suited to specific tooling types and processes. Tool steels in general are classified into several broad groups, and some are subdivided further according to alloy composition, hardenability, or similarities in properties. Most forging companies use two basic die steels for forge dies: Pre-hardened FX material (or equivalent), or annealed H13. Cost and availability are the main driving factors for selection of these materials. Forgers deviate from this pattern when premature failures start to appear. Often, a desired production rate is not being achieved, or a forge run is interrupted because one or more areas of the die impression begins to produce an unacceptable part dimension. The hunt then begins for a die material that will support the run free from dimensional defects. Forge shops address the issue in a variety of ways. H13 tool steel, a chromium-molybdenum hot work steel, is chosen due to its hot hardness that is resistant to thermal fatigue cracking associated with cyclic heating and cooling cycles. With its combination of toughness and crack resistance, it is the most used steel for hot working applications.

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FIA MAGAZINE | FEBRUARY 2021