Inside the factory, the equipment department or user department is responsible for the large industrial fans. To ensure the good operation of the industrial fans, it is necessary to arrange for maintenance personnel to carry out regular maintenance, especially when the fan encounters a fault, it is necessary to carry out inspection and troubleshooting. For most large industrial fans on the market, fault detection and troubleshooting mainly include the following contents.
Fault detection and troubleshooting methods
When encountering a fault, first of all, it is necessary to effectively analyze and judge the large industrial fan to find out the fault point. According to industry experience, there are 6 most commonly used judgment methods
Dharma, that is, seeing, hearing, smelling, touching, measuring, and doing. Look: Observe the abnormal shape of the fan components. Such as whether the fasteners are loose, or whether the insulator is carbonized and blackened. Listen: Listen to the change of the sound of the fan when it is running to judge the working condition. For example, the asynchronous motor cannot be started in one item, and at the same time it emits a "metaphor" sound; when the motor bearing is damaged, it emits a "rustling" sound, etc.
Smell: Smell the smell emitted by the equipment when it is running. If the temperature rise exceeds the limit due to short circuits, overload, and other faults, a pungent burnt smell may appear.
Touch: Roughly judge whether the fan is running normally by touching the temperature of the device casing.
General steps for troubleshooting
Usually, when troubleshooting a large industrial fan, the steps adopted can be roughly divided into symptom analysis-equipment inspection-determining the fault point-performance observation after troubleshooting
1) Symptom analysis
Symptom analysis is the process of collecting and judging all possible information about the original state of the fault. All information should be carefully analyzed before malfunction indications are disturbed. This original information can generally be obtained from the following aspects:
1. Access the operator. To obtain information about the use and change process of the fan, before and after damage or failure, you can also learn about similar failure phenomena, causes, and measures that have been taken in the past.
2. Observation and preliminary inspection. A comprehensive look at industrial fans can often yield valuable clues. The content of the preliminary inspection includes the detection device, checking the position of the operation switch, the control mechanism, the adjustment device, etc.
3. Start the device. Under normal circumstances, the operator should be required to start the equipment according to the normal operating procedures. If the failure is not a failure of the complete machine loss control system, the fan can be turned on by trial operation to help the maintenance personnel have a comprehensive impression of the original state of the failure. Analyze the actual situation, and deduce the clues of the most likely fault area from it as a reference for the next equipment inspection. But be careful not to make premature judgments based on inaccurate indications or insufficient information
(2) Equipment inspection
Based on initial conclusions and doubts raised during the large industrial fan symptom analysis, a more detailed examination of the equipment was carried out, especially those areas considered most likely to be faulty. It should be noted that at this stage, unnecessary disassembly of the equipment should be avoided as far as possible to prevent more failures caused by careless operations. Do not adjust the control device easily, because in general, blind adjustment of parameters without troubleshooting will cover up symptoms, and with the development of the fault, the symptoms will reappear and may cause a more serious fault, so it is necessary to avoid blindness, prevent the fault from being complicated due to careless operation, and avoid causing symptom confusion and prolonging the troubleshooting time.
(3) Determining the point of failure
According to the fault phenomenon, analyze and judge according to the principle and control characteristics of the industrial fan, and determine the scope of the fault, is it an electrical fault or a mechanical fault? Is it a DC circuit or an AC circuit? Is it the main circuit or the control circuit or the auxiliary circuit? Is it caused by the power supply part or improper parameter adjustment? Is it caused by man-made or random? According to the previous symptom analysis and equipment inspection, use the "general method of troubleshooting" flexibly to gradually narrow down the scope of the fault until the fault is found. point of failure. If the diagnostic information of the system is lacking, maintenance personnel need to correctly divide the entire equipment or control system into several small parts, and then check whether the input and output of these parts are normal. When determining a certain part, pay attention to the internal problems of this part and find out the fault point.
After determining the point of failure, whether it is repair or replacement, troubleshooting is generally much simpler for maintenance personnel than finding the fault. but in excluding
It is generally impossible to use only a single method in obstacles, and often multiple methods are used comprehensively. 1. In the process of troubleshooting, you should use your brain first and then do it. Correct analysis can achieve twice the result with half the effort. Specifically, it should follow the principles of first external and then internal, first mechanical city and then electrical, first static and then dynamic, first public and then special, first simple and then complex, and first general and then special. It should be noted that as soon as you encounter a fault, you should not pick up the watch to measure it and pick up the tool to dismantle it. To develop a good habit of analysis and judgment, each measurement must have a clear purpose, that is, what can the measurement result show? After finding out the component with the fault point, the root cause of the fault should be further determined.
2. Under normal circumstances, the order of analysis and detection during exclusion is based on the action sequence of the equipment. Based on this premise, first, check the power supply, then check the circuit and load, first, check the public circuit and then check each branch circuit, first check the main circuit and then check the control circuit, first check the easy-to-detect parts, and then check the difficult-to-detect parts
(5) Post-repair performance observation After the fault is eliminated, the maintenance personnel should do a further inspection before power transmission, and the inspection confirms that the fault has been eliminated, and then the operator will perform a trial run to confirm whether the equipment is operating normally. At the same time, the problems that should be paid attention to should be explained to the relevant personnel. Troubleshooting of large industrial fans is the basic task of equipment managers in every workshop. In addition to daily maintenance to avoid failures, they must also be able to quickly find out the cause of the failure and handle the failure point reasonably and correctly when encountering a failure. Improving labor productivity, reducing economic losses, and safe production all play a major role