IndexRaw MaterialSheet and Plate DrawingDrawing RatioReductionDrawing ForceSealing ForceSheet Metal IroningCleaning and DecoratingTop Neck FormingThe LidFilling and SeamingRaw MaterialThe drink may be made primarily of aluminum, but also contains small amounts of other metals. These are typically 1% magnesium, 1% manganese, 0.4% iron, 0.2% silicon and 0.15% copper. Before we understand the beverage can manufacturing process, we will need to understand the sheet metal and sheet metal drawing processes. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Sheet and Plate Drawing In the drawing process, a combination of a punch and die is used that draws a circular blank of sheet metal into a 3 :Green cylindrical cup. Basically, the punch drops, pushing the metal through the die, converting the circular blank into a cylindrical cup. The height of the cup walls is determined by the difference between the diameter of the original blank and the diameter of the punch. The drawing operation is performed in multiple steps and is not a one-step process. Wrinkles may appear on the walls of the cup as the circumference is reduced, or the punch may act as a punching tool. If the gap between punch and die is less than the thickness of the incoming material, the cup wall is thinned and elongated. This process is often called ironing or wall ironing. The punch and die must have corner radii, given by Rp and Rd. The sides of the punch and die are separated by a free space c. For drawing, the distance is greater than the thickness of the blank as follows: As the punch begins to push into the workpiece, the metal is subjected to a bending operation. As the punch moves downward, there is a straightening action of the previously bent metal relative to the die radius. Holding force is critical to a successful drawing operation. If too small, wrinkles form, if too large they prevent the metal from flowing correctly towards the mold cavity. This causes stretching and possible tearing of the sheet metal. Draw Ratio For a cylindrical shape, the draw ratio is the ratio of the blank diameter Db to the punch diameter Dp. The higher the ratio, the more serious the operation. An approximate upper limit of the drawing ratio=2.0ReductionFor a given drawing operation, the reduction 'r' is also used as: Thickness/Diameter Ratio A third measurement in deep drawing is the thickness/diameter ratio, which gives the tendency to wrinkling It is desirable that the t/Db ratio >1%. As t/Db decreases, the tendency to wrinkle formation increases. In cases where these draw ratio, reduction, and t/Db ratio limits are exceeded by the design of the drawn part, the blank must be drawn in two or more passes, sometimes with annealing between passes. The Drawing ForceForce equation estimates the maximum force in the operation Where, F=drawing force, N, t=original blank thickness, mm, TS=tensile strength, MPa, and Db and Dp are the initial diameter of the blank and the diameter of the punch, mm. The constant 0.7 is a correction factor to account for friction. Holding force As a rough approximation, the holding pressure can be set to a value = 0.015 of the sheet metal yield strength. This value is then multiplied by that portion of the initial area of ​​the blank that must be retained by the blank holder. In eq. shape The holding force is.