Specifies the crotch radius of the formed lip on an extruded welding tee, intersection type 6. This is also the intersection weld crotch radius for WRC329 calculations. Specifying this value can result in a 50% reduction in the stress intensification at the WRC 329 intersection. If you attempt to reduce the stress riser at a fabricated intersection by guaranteeing that there is a smooth transition radius from the header to the branch pipe, then you may reduce the resulting stress intensification by a factor of 2.0.