Several aspects of stepped environmental loads application in evaluation and improvement of the quality of equipment

摘要

The supplier of a system was interested in comparing the capability of one of the system's main components,supplied by three different suppliers,to withstand the loads of a 10 year life-cycle.One of the three models of the test component is currently in use,with a proven high capability.Two alternative models were proposed by new suppliers,and their quality had to be tested.The system's life cycle is characterized by thermal and dynamic loads that affect its performance. In order to compare the quality of the test component from the three suppliers, a testing program was planned,in which the test component was exposed to a sequence of accelerated dynamic and climatic loads.The dynamic conditions were derived through measurements,and consist of a sequence of mechanical shocks.The climatic conditions were derived from analysis of the thermal and humidity loads of the life-cycle.Not all the tested components withstood the accelerated loads.By applying the stepped-load sequence the weaknesses were revealed,corrected for,and the components retested. The paper presents the problem,continues by analyzing the life-cycle's loads (dynamic and climatic),followed by presentation of the possible failures,description of the test results for the test components,the surfaced weaknesses,the corrective actions,and the repeated testing.Several summarizing remarks related to the use of stepped loads conclude the paper.