Abstract: A method of forming a composite nut having a threaded connection in which the axial load between a screw and nut in a tightened condition of the connection is distributed more uniformly between different turns of the engaged threads than in a standard threaded connection by forming the nut to have a pitch which increases progressively as the thread advances helically in a predetermined axial direction, while the other thread desirably has a pitch which is uniform along its length. The pitch of the first thread may increase at a rate predetermined to compensate for differences in the tensile force which is applied to the screw and the compressive force applied to the nut at different points along their length when the screw and nut are tightened together to a prestressed condition.

Abstract: A gauge and gauging method for measuring a thread of varying pitch by screwing a threaded gauge element into engagement with the thread of varying pitch and to a point at which the threads have a light binding relationship resisting further advancement of the threads together. The device is constructed to then indicate the extent to which the gauge element has advanced when the binding condition is attained, and utilize that reading as a measurement of the functional accuracy of the thread of varying pitch. The device preferably includes a second element which, when the threads are in their lightly binding condition, is adjustable axially relative to the threaded gauge element and to a position of contact with the part containing the thread of varying pitch. Markings indicating the relative positioning of the two elements then provide a precise measurement of the functional accuracy of the thread of varying pitch.

Abstract: A threaded connection in which the axial load between a screw and nut in a tightened condition of the connection is distributed more uniformly between different turns of the engaged threads than in a standard threaded connection by forming one of the threaded elements, preferably the nut, to have a pitch which increases progressively as the thread advances helically in a predetermined axial direction, while the other thread desirably has a pitch which is uniform along its length. The pitch of the first thread may increase at a rate predetermined to compensate for differences in the tensile force which is applied to the screw and the compressive force applied to the nut at different points along their length when the screw and nut are tightened together to a prestressed condition.