US Patent 7153071 Device for chip forming machining

A device for chip forming machining including first and second rotatable bodies arranged along a common axis of rotation. The first body forms a male element, and the second body forms a female element into which the male element is threaded for forming a threaded joint. The male element has an outer circumferential area displaced in the axial direction in relation to the thread thereof and which engages a corresponding inner circumferential area of the female element by a press-fit. One or both of those circumferential areas has an out-of-roundness, such that there occurs a press-fit along two or more preselected regions in the circumferential direction.