The acquisition of fault information is the first step in the fault diagnosis and removal of the excavator. It is a process for people to find out the problems according to intuition, knowledge and experience. It is usually summed up in two methods: visual inspection and precision diagnosis.
1. intuitionistic examination
This method refers to the initial qualitative classification of the fault by means of personal feeling and experience or using simple instruments, through the intuitionistic methods of watching, listening, touching, smelling, reading and asking, such as obtaining valuable information from appearance, vibration, abnormal sound, Wen Sheng, smell, wear and so on. It is a preliminary judgment of the cause or location of the failure. The simplest method is the most commonly used traditional diagnostic method.
2. precision diagnosis
On the basis of the visual inspection method, this method uses the precise measuring instruments to take a scientific method to carry out static and dynamic test and quantitative analysis of the key parts or projects, and find some difficult and difficult hidden fault information to determine the fault location and degree accurately. For example, the vibration signal analysis method, the oil spectrum spectrum. And ferrography, etc. when necessary, special simulation tests or practical tests can be carried out for a specific system or component.
The instrument used in this method is more precise and cost high. It needs higher theoretical level and technical accomplishment when analyzing the acquired signal. At the same time, it is still inseparable from the guidance of practical experience. At present, it is still in the perfection of research and improvement.
3. epistemological problems of the two methods
Both the visual inspection and the precision diagnosis are the effective methods to obtain the fault information, but they are different at the level of the cognitive problem, and the theoretical thinking degree of the main and objective conditions is far apart.
1) from the objective point of view, there are various types of excavators, different structures and different technical complexity; the degree of failure (incubation period, development period, damage period) and troubleshooting are different, and the instruments, tools and maintenance conditions are different. The above factors must be fully considered in the process of diagnosis and maintenance.
2) from the subjective point of view, the technical quality of the maintenance personnel is high and low, the practical experience is strong and weak. The sensitivity is different to the fault of different institutions or to the same machine, and the information needed in the diagnosis and elimination is different.
Because the main and objective factors directly affect the reliability, sufficiency and clarity of the acquired fault information, the correct diagnostic conclusions need to be obtained through different theoretical modes of thinking.
The above two methods are interrelated and complementary, and are consistent with the overall goal of identifying the nature, location and cause of the fault.
