Sheet Metal Blanking Process:
The sheet metal blanking process is a one of the shearing operation. Blanking process is cutting process obtain in sheet metal in which sheet metal piece is removed from the large piece of stock by shearing force applied in the sheet metal. When the blanking of sheet metal process the removal of piece is called as “blank”. It is not scrap also, but rather than desired part shape. The metal left is considered in the die called as die waste. which blanking operation can be used to cutout of sheet metal in such as a almost any 2D shape, but it is most commonly used in cut of work piece With simple of geometric. It will be shaped in subsequent process. Sometime multiple sheet metal are blanked with in an single operation final products by using that blanking operation such as jewelry, gears and clock or watch components. After blanking operation, the parts will be require secondary finish to smooth out burrs with bottom edge.The fine blanking process is most method of blanking.
The sheet metal blanking process is require such as blanking punch, blanking die, blanking press and sheet metal stock. The sheet metal is placed on the blanking press of die. The die cavity instead of have a cutout shape of desired shape and made of standard shape is formed together. The blanking punch act as tool in the desired shape above the sheet metal. Either both punch and die are made with carbide or tool steel. When the blanking process, the punch downward with high speed into sheet metal by using hydraulic press drive. The small of clearance provided in between punch and die. The clearance range is 10- 20% of metal thickness. Now the punch is impact into the sheet metal, and quickly bends and then fractures together. The blank is sheared the stock fall into gap in the die. This process typically fast, and require some blanking presses to perform over 1000 stroke/ minute.
Fine blanking process:
Fine blanking process is one the specialize type of process. Which blanking process sheared the sheet metal in three type of force separately applied. The fine blanking provides parts having smooth edge better flatness and high tolerance. It ranges from ± 0.0003. It can be make high quality parts without any secondary operation require. But that require tools and additional equipment for making high volume production with better suited.
It tools and equipment very similar to conventional blanking operation. The sheet stock is placed on the blanking die with hydraulic press and then the punch impact the sheet metal to remove blank parts. During the process the part done by 3 type of force applied.
First force is downward force apply to top of sheet metal. That is act as holding force during the process. The clamping force holds a guide plate with tightly then again the sheet metal holds in placed an impingement ring. It is called stinger.
It is forced applied on under heath of sheet metal and it acts as directly opposite to the punch, it called as Cashion. That provides counting force during the blank operation and eject from blank. That two type of force help to sheet metal bending reduced and improving flatness of blank.
It force applied by the blanking punch impact the sheet metal and sheared the blank into die opening. The clearance provided in between punch and die the range of 0.001 inches. The blanking operation perform at slowly. The metal fracturing into free the blank then blank flow is extruded to provide a smooth edge of blank.
The fine blanking parts can be making as follow:
By using the fine blanking process to made following products