In stamping, we classify every operation by how the material deforms: separation and forming. Separation covers shearing, blanking, and punching, where the sheet is cut along a closed contour. Forming covers bending, drawing, flanging, and coining, where the material is reshaped without fracture. The three core operations—blanking, bending, and drawing—form the backbone of most sheet metal parts. Blanking determines blank quality and burr height; bending controls springback and bend radius; drawing governs wall thickness distribution and wrinkle suppression. In the tool room, these aren't abstract categories. They dictate die clearance, punch and die material selection, and whether we need a single-station or progressive die.

Take blanking: clearance is typically 5–10% of sheet thickness per side, depending on material. Too tight, and you get secondary shear and die wear; too loose, and the edge tears. For bending, springback compensation is built into the die angle—often 1–3 degrees overbend for mild steel, more for high-strength alloys. Drawing is the most demanding. Draw radius, blank holder force, and lubrication all interact. A typical deep-drawn cup might need a draw ratio under 2.0 per pass to avoid tearing. These are the numbers that separate a die that runs 500,000 strokes from one that fails at 50,000.

In practice, we don't treat these operations in isolation. A progressive die might combine blanking, bending, and drawing in one strip, and the sequence affects strip layout, piloting, and scrap removal. Understanding the deformation mechanics behind each station is what lets you troubleshoot wrinkles, cracks, and dimensional drift on the shop floor. For more mold sourcing and technical resources, visit MoldWorld at www.moldw.com.