On occasion,the die design may create a situation in which the path of least resistance is the one that results in a defect during drop forging. It is imperative that the die and preform design creat this least resistant path so that the final result is a sound drop forging. When the pressor hammer dies close, the workpiece will move in a path of least resistance. By understanding the process issues, the drop forging is better able to design its processes to minumize the occurrence of such defects. Less than optimum process and preform design is the principal cause of most geometrical defects. This is caused mainly by the improper design of dies.Where in the corner and the fillet radii are small as a result of which metal does not flow properly into the corner and rhe ends up as a cold shut. *Cold shut: This defect appears as a small cracks at the corner of drop forging. This defects happen due to the improper design of drop forging dies or not using the right forging process. *Unfilled defects: There may exsit some sections of die cavity not completely filled by the flowing steel. *Laps and folds: Laps and folds are produced due to improper design of drop forging dies, making the laps created onto the final component which is rather undesirable as make irregular surface finish and also may weaken the product for internal or external cracks. Such drop forging defects can be split into two broad types: geometrical defects and non geometrical defects. Although there are a variety of advantages of drop forging technology compared to other metal forming processes,there may still exsit some defects in hot forging process.
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