Shearing is a process of cutting flat product with blades, rotary cutters, or with the aid of a blanking or punching die. This article commences with a description of some wear and material factors for tools used to shear flat product, principally sheet. Methods of wear control are reviewed in terms of tool materials, coatings and surface treatments, and lubrication. The article discusses tool steels that are used for cold and hot shearing, and rotary slitting. It provides information on the materials used for two main categories of machine knives: circular knives and straight knife cutters. The article also discusses the selection of materials for blanking and piercing dies and provides examples that illustrate the various types of tooling changes for blanking high-carbon steel.

Many shearing, blanking, and piercing operations are based on the same underlying principles of shear mechanisms. This article provides information on the various operations associated with die cutting and describes three phases involved in the shear cutting or punching action. These phases include deformation, penetration and fracture. The article also explains the effect of clearance on tool life and force and power requirements. It reviews the forces involved in the punching process and describes the diameter of a hole or blank in relation to material thickness. The limitations of punching are also discussed. The article describes the relationship of the die clearance to stress-strain curves and explains the procedure of interpreting the stress-strain curves. The article concludes with information on the dynamic stripping forces in blanking.

This article discusses the tribology of three main sheet forming processes: deep drawing, bending, and shearing. For each process, the basic principle of the forming process is briefly explained. Tribological phenomena observed in each process, such as wear and galling, are presented. Common methods of using lubricants and coatings in sheet forming processes are also described.

This article discusses the principles of the press-brake forming process and its applicability with an example. It describes the types of press brakes and examines some considerations, which help in the selection of machine. The article provides information on flattening dies, gooseneck punches, wiping dies, channel dies, arbor-type punches, box-forming dies, curling dies, beading dies, and cam-driven dies, with illustrations. It discusses the tool material selection for various operations. The article explains the procedures used for producing different shapes, including simple boxlike parts, panels, flanged parts, architectural columns, fully closed parts, and semicircular parts. It examines the effect of work metal variables on results in press-brake operations. The article also reviews stock tolerances, design, and condition of machines and tools, which help in obtaining good dimensional accuracy.

Powder metallurgy compacting presses usually are mechanically or hydraulically driven, but they can incorporate a combination of mechanically, hydraulically, and pneumatically driven systems. This article provides a comparison of mechanical and hydraulic presses based on the cost, production rate, and machine overload protection. The article lists the classification of powder metallurgy parts based on complexity of shapes as suggested by the Metal Powder Industries Federation, such as Class I parts, Class II parts, Class III parts, and Class IV parts. It describes rigid tooling compaction and details the powder-fill ratio considerations for these classes. The article elaborates on the types of tooling systems and presses used for these classes. Some important factors and components used in designing a tool are also described. Finally, the article considers tool materials, including punches, core rods, and punch clamp rings.

This article illustrates the characteristics of pierced holes and summarizes the hole wall quality. Specific guidance in selecting die clearances is provided by considering the types of edges produced with different clearances. The article discusses the effect of tool dulling and the use of small and large clearance. It informs that the force needed to pierce a given material depends on the shear strength of the work metal, the peripheral size of the hole or holes to be pierced, stock thickness, and depth of shear on the punch. The article discusses the presses and tools used in piercing. It illustrates the use of compound dies, progressive dies, and transfer dies; piercing of thick and thin stock and piercing holes at an angle to the surface; special piercing techniques; and shaving of low-carbon steels.