Frequently Asked Questions

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What factors are considered in the selection of steel grades for pharmaceutical tooling?

TOOL STEEL SELECTION AND APPLICATION:
Among the many factors that go into steel selection for the manufacture of punches and dies for the tableting press are tonnage required, chemical atmosphere, abrasive nature of the product, turntable speed, cup depth, amount and location of embossing, bisect, land and physical condition of the press.

For general punch applications shock-resisting steels, S grades, are chosen because they combines high strength, high toughness and low to medium wear resistance. The principal alloying elements in these shock resistant grades, S-1, S-5, and S-7, are manganese, silicon, chromium, tungsten, and molybdenum in various combinations. These grades are commonly referred to as Standard Steels. The Elizabeth Standard is a proprietary formulated special melt S-7.

For high wear applications D-2, D-3, and A-1 high-carbon, high-chrome grades of steel are recommended. These steels are abrasive resistant but do not have the ductility or toughness of the S grades of steel. D-2 punches therefore are susceptible to cracking and caution must be exercised in applications with embossed punches, deep bisects, and/or deep cups. D-3 because of it high wear resistance is used primarily for dies. These grades are referred to as Premium Steels for compacting tooling.

For corrosive products 440C Stainless is used for the punches. This grade has a low toughness rating and the wear resistance falls between the S and D series of steels. Although there are other 400 grades of stainless steel that can be hardened, the 440C grade is the one best suited to meet the requirements for tablet tooling.

No single tool steel material combines maximum wear resistance, toughness, and resistance to corrosion. Consequently, the selection of the proper tool material for punches and dies for application may require a trade-off to achieve the optimal combination of properties.

EFFECTS OF THE ALLOY ELEMENTS IN TOOL STEEL:

CARBON (C)