Detection includes inspection, measurement and fault analysis. The so-called inspection, generally through the visual method of looking, touching, listening and hearing, that is to say, "look at the surface, touch its temperature, listen to its voice and ask its taste", carries on the inspection to the equipment condition, in order to determine whether the equipment works normally; and the measurement refers to the use of various measuring instruments and instruments to test the equipment and parts, in order to determine whether they meet the requirements and meet the work needs; The analysis is aimed at the abnormal phenomena such as sound, temperature and odor found in the inspection, and makes scientific analysis and judgment based on the previous operation and maintenance records, as the basis for making repair plans and repair plans.