This series of articles investigates the many causes of premature punch breakage in stamping operations.

The stainless steel stampings Viking Range produces often require complex draws and piercing, as well as sharp corners and creases—with flawless exterior finishes. Viking has moved from outsourcing its stampings to using press brakes to investing in hydraulic presses of increasing capacity and sophistication—all in an effort to gain greater control over the design, quality, and availability of stamped parts.

Draw forming is one of the net shape processes, and, as a result, many of the technology advances in the general field of manufacturing have not been as beneficial to draw forming as one would expect. All too often, such advancements as lean manufacturing, statistical process control, just-in-time, and six sigma, have not resulted in benefits for draw forming.

Forming lubricants always have been a critical component in the metal forming process, but the performance characteristics of these products are even more essential when working with HSS.

Numerous factors contribute to the premature failure or breakage of piercing and cutting punches. Two common factors are operator error and incorrect die cutting clearance.

Hot-stamped parts are being used increasingly in cars in Europe and North America. Ultrahigh-strength steels, like boron alloys, which meet automotive safety and crash requirements, are difficut to form with cold stamping, so hot stamping with die quenching has been applied.