"Shearing" by itself refers to a specific cutting process that produces straight line cuts to separate a piece of sheet metal. Most commonly, shearing is used to cut a sheet parallel to an existing edge which is held square, but angled cuts can be made as well. For this reason, shearing is primarily used to cut sheet stock into smaller sizes in preparation for other processes. Shearing has the following capabilities:
Sheet thickness: 0.005-0.25 inches
Tolerance: ±0.1 inches (±0.005 inches feasible) Surface finish: 250-1000 μin (125-2000 μin feasible)
The shearing process is performed on a shear machine, often called a squaring shear or power shear, that can be operated manually (by hand or foot) or by hydraulic, pneumatic, or electric power. A typical shear machine includes a table with support arms to hold the sheet, stops or guides to secure the sheet, upper and lower straight-edge blades, and a gauging device to precisely position the sheet. The sheet is placed between the upper and lower blade, which are then forced together against the sheet, cutting the material. In most devices, the lower blade remains stationary while the upper blade is forced downward. The upper blade is slightly offset from the lower blade, approximately 5-10% of the sheet thickness. Also, the upper blade is usually angled so that the cut progresses from one end to the other, thus reducing the required force. The blades used in these machines typically have a square edge rather than a knife-edge and are available in different materials, such as low alloy steel and high-carbon steel.
Metal Cutting Skills
- Acuracy 98%
- Precision 95%
- Tolerance 90%
- Finishing 98%
- Wastage 10%
Sheet Coil/Plate Shearing
Shearing, also known as die cutting,is a process which cuts metals without the formation of chips or the use of burning or melting.
A punch (or moving blade) is used to push the workpiece against the die (or fixed blade), which is fixed. Usually the clearance between the two is 5 to 40% of the thickness of the material, but dependent on the material.
The processes of straight shearing is done on sheet metal, coils, and plates. It uses a guillotine shear.