Abstract: The concept of disposable mechanical elements is proposed. Disposable mechanical elements with extremely short lives are widely used in the aerospace and some other special fields. Disposable mechanical elements have smaller volume and lighter weight than general mechanical elements. During the running process of disposable mechanical elements, high cycle fatigue failure will not occur. Until now, there is no systematically design theory used in the disposable mechanical elements design. Therefore, the static strength design criteria is proposed which could take place of high cycle fatigue failure checking in the disposable mechanical elements design, which could decrease the volume and weight of mechanical elements. The design theory is used in the design of bevel and fleshliness of certain type rocket steering reducer. Under the same load level, the gear modulus reduces by 40% by using the disposable mechanical elements. An experiment is conducted to test the performance of the reducer. The experiment result shows that the reducer could meet the requirement of the initial design targets. It is proved that the disposable mechanical elements design theory is fairly effective.

Key words: disposable mechanical elements;mechanical design;electric steering engine reducer