Machine Parts

The punch contacts the work piece material supported by the die & a pressure buildup occurs. When the elastic limit of the work material is exceeding, the material begins to flow plastically. The punch penetrates the work material & the blank is displaced into the die opening a corresponding amount. A radius is formed on the top edge of the hole & the bottom edge of the blank according to figure  Compression of the slug material against the walls of the die opening burnishes a portion of the edge of the blank according to figure  At the same time the plastic flow pulls the material around the punch, causing a corresponding burnished area in the work material. Further continuation of the punching pressure then starts fractures at the cutting edge of the punch & die. Under ideal cutting conditions, the fractures will meet & the remaining portion of the slug edge will be broken away. A slight tensile bar will be formed along the top edge o

Plain Blanking: The plain blanking operation consists of a punch going through the material during the working stroke & on the return stroke the material is lifted with the punch & is removed by stripped plate. Piercing: The operation consists of simple hole punching. Punching is the scrap & the strip is the work piece.    Cutting off: A cut off operation separates the work material along straight line in a single line cut. Shaving: Shaving is a secondary operation, usually following punching, in which the surface of the previously cut edge is finished smoothly to accurate dimensions.

Progression ratio: The ratio of maximum speed to the minimum speed is called progression ratio. It is represented by Φ. Machine Tool drive: The tools whice are driven by the power known as machine tools. working principle of hydraulic drive:   hydraulic drive is machine tools use the pressurized oil to transmit energy. The high viscous oil is used for this purpose. The pressurized oil from the pump is transmitted through the pipe to a hydraulic motor where the motor is set to motion. These are positive dispalcement pumps because the energy conversion takes place during the process of oil in the working chamber. Advantages of hydraulic drive:   1.       Realtively small dimension and weight 2.       Quiet running and self lubricating 3.       possiblity of high cutting and clamping force 4.       The possiblity of simple and smooth speed reversion Disadvantages of hydraulic drive:                                 1.The high accuracy o

PIV Drive: A stepless drive where the transmission of torque takes place infinitly variable without   slip is called PIV drive. There are some advantages of PIV drive: there is no slip in the transmission of power. Maximum transmission of power. Speed can be changed at running condition Any range of slip can be obtain It give constant cutting speed for the above reason PIV drive is more effective than any other system   of drive