The Press Brake Tonnage Chart is a valuable reference chart when air-bending metal on a press brake. When forming metal up to 1/2″ thick, we generally use a 8:1 ratio between the v-die opening and the material thickness. For 1/4″ material, you would use a 2″ v-die. From the chart- when you know the material thickness and type- you are able to determine with some accuracy the tonnage requirements using the different v-die openings. Keep in mind, the chart is calculated on forming mild steel. The chart will also provide the minimum flange length and the inside radius the different v-die openings will produce.
When forming materials 1/2″ and over – the recommended v-die opening ratio is 10:1 to material thickness.
