The form tapping process typically yields unfinished threads known as split crests. Thread quality can be greatly improved by reducing the size and severity of split crest formation. This paper develops a finite element model to simulate form tapping with an eye towards the reduction of split crests. The model is validated against linear scratch experiments, and simulations are compared to actual tapping. The effects of various tap design parameters and tapping process conditions on the formation of split crests are investigated to strive toward an optimal tap design.

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