Have you ever heard of punching machines? A punching machine is used to drill and shape sheets of different materials through a punch and a die. The punching machines can be simple, formed by a single set of tools, or more complex, automatic with multiple tools. The punching system is an automated mechanical operation. Through special tools called punches, making holes in sheets and separating a metal part from another, obtaining a certain figure is possible.
- Thanks to the punching machine, pieces of material are removed from a sheet using punches activated by a press.
- What is needed to make a hole in a sheet is: punch, hold or separator, and matrix. To make the hole in a certain shape and dimensions, these elements must have the same shape.
We can differentiate several types of punching machines:
Turret punching machines: this type of machine has a double drum where the punching tools are housed. This tooling consists of a punch holder that is mounted on the top turret of the drum. The rotating matrix is mounted according to the program in the lower turret to select the necessary tools to make the piece.
Punching machines: this type has a tooling store. The machine will pick up and leave the tools of that store. Each warehouse position has a cassette where the punch, the separator, the matrix, and an orientation ring are mounted.
- There are two processes, cutting and punching. The cutting process consists of separating a portion of material along a line defined by one or several elements. The punching consists of the complete cutting of a closed perimeter figure made on a sheet’s surface.
The two models of punching machines described above have a very similar punching cycle:
Turret punching machine: the punching machine will rotate the turret and place the tooling just below the Servo Electric Punching Machines’ hammer. From that moment, the hammer will descend, pushing the punch holder. The presser will contact the sheet, pressing and holding the sheet keeping it flat against the matrix. The hammer will continue to lower, compressing the springs of the punch holder and lowering the punch. The punch will initiate the sheet’s penetration producing a small curvature around the cutting edge of the punch and the matrix.
Next, a cutting phase will begin, later becoming a fracture in the sheet, both in the upper and lower part due to the material’s start. When the previous fractures coincide, the retail corresponding to the hole will be loose from the sheet. The hammer will continue down to its lower limit to facilitate the fall of the scrap. Then the hammer will go up, and the springs of the container will extract the punch from the sheet while the presser keeps the plate completely flat.