Practice shows that it is necessary to control threaded joint’s assembly tightness when mounting or due to the exploitation. If this condition is not provided in necessary quality and tightness is insufficient or too big, it may cause threaded joint’s damage. The most popular methods for the threaded joint’s assembly control in machine manufacturing are as following: 1) measurement of the screw’s prolongation; 2) control of the screw-nut’s turning angle; 3) measurement of the screw-nut’s tightness moment. The most exact results provide the measurement of the screw’s prolongation. This method is widely used when controlling threaded joint’s tightness for very responsible assembly units, for example, for pitman screw joints.