IMPROVEMENTS IN HIGH STRENGTH FASTENER ASSEMBLY

摘要

A fastening system including a two piece swage type fastener including a pin and a collar in which the pin has shallow lock grooves having a ratio of (h/Du)x10<2> of four (4) or less and in which the lock grooves have a simulated streamlined root contour generally defined by a portion of an ellipse, with the collar having a wall thickness defining a volume of material sufficient to provide overpacking of the shallow grooves of around 16% and to provide a clamp load of between around 85% to around 95% of the yield point of the pin, and with the pin and collar materials having ultimate shear strengths in a ratio of around 1.8:1 to 2.4:1 and with the width of the shallow pin grooves and intervening shoulders being generally in accordance with the shear strength ratio between the pin and collar.