Analysis on the application of nondestructive testing technology in the maintenance of coal mine machinery and equipment
August 16, 2024 Hawk
Nondestructive testing technology refers to the detection of optical or magnetic changes caused by material structure or defects in equipment without affecting or causing damage to the test object. Since nondestructive testing technology has strong comprehensiveness, it has been widely used in industrial industries in various countries. In coal mining projects, in order to further ensure the normal operation of mechanical equipment, this article will analyze the application of nondestructive testing technology in equipment maintenance.
In the process of coal mining, the operation time of mechanical equipment at the mining site is relatively long. In addition, the operating environment of these mechanical equipment is poor, there is a lot of dust, and some equipment even needs to be overloaded. Therefore, the probability of mechanical equipment failure at the coal mining site is still relatively high. In the maintenance of mechanical equipment, nondestructive testing technology can help staff accurately detect the location and type of defects or problems in mechanical equipment. Compared with the more traditional equipment detection methods in the past, nondestructive testing technology not only requires shorter detection time, but also more accurate detection results. If maintenance personnel can actively use nondestructive testing technology in equipment maintenance work, it can not only improve the maintenance quality of equipment, but also ensure the stable production of coal mines.
1 Problems in the maintenance of coal mine machinery and equipment
1.1 Problems in the maintenance and management of machinery and equipment
Many enterprises do not do a good job in the maintenance and management of equipment during coal mining. Most of these enterprises ignore the management of equipment for economic benefits. The most important thing for the maintenance and management of mechanical equipment is to maintain these mechanical equipment. Under certain requirements, anti-corrosion and lubrication work should also be carried out regularly. In order to save money, many enterprises use lubricants of relatively low quality. Multiple equipment use this lubricant for a long time. Although the machine is maintained to a certain extent, it has great damage to the machine, which may cause the machine to work unstably in the later stage, and directly affect the efficiency and quality of the entire production.
1.2 Lack of advanced mechanical equipment maintenance management model
At present, many enterprises still use the relatively backward maintenance management model in the past, but the current production with relatively large demand has a relatively large loss on the machine. If the past maintenance management model is still used, the maintenance and maintenance of many mechanical equipment will not achieve the best results. While innovating in other aspects, there is no emphasis on the update of equipment. At the same time, the increase in production volume has caused a lot of load on many machines, and the life of the machine is also greatly reduced. Now, in order to improve the mining efficiency of coal mines, although equipment R&D personnel are constantly researching advanced mechanical equipment, many enterprises have not introduced these advanced mechanical equipment, and have not improved the backward maintenance management model used internally. Under this working background, not only the probability of mechanical equipment failure cannot be reduced, but also the effect of equipment maintenance work is difficult to guarantee.
1.3 Lack of a perfect mechanical equipment maintenance management system
Many enterprises only focus on the maintenance of mechanical equipment during the production process, but if enterprises want to obtain more benefits, they must also start from the management system and improve a set of management systems that belong to the enterprise itself. Many enterprises have not established independent equipment maintenance departments during the coal mining process, lack some project system management persons in charge, and the entire coal mining chain has not been properly arranged. A large number of problems that arise during the mining process are not handled by relevant persons in charge, and there is no reasonable division of labor for the subsequent maintenance of mechanical equipment. These may cause some mechanical equipment to not receive regular maintenance and maintenance, causing great damage to the equipment, and subsequent work cannot operate normally, and the mining plan of the entire coal mine and project will also be delayed.
1.4 Problems in the daily maintenance of coal mine machinery and equipment
There are also a lot of problems in the daily maintenance of coal mine machinery and equipment. Although the maintenance and maintenance of equipment is the most important, it is in this process that the most problems exist. When some employees are performing maintenance work, improper operation will not only damage the machine, but also the maintenance staff may be injured. Since many materials are chemical fuels, they are very harmful to the human body. Therefore, maintenance personnel must standardize their operating steps and wear corresponding safety protection equipment.
2 Types of non-destructive testing technology
2.1 Radiation detection technology
The application range of radiation detection technology is very wide, and it is also often used in non-destructive testing of equipment. Radiation detection technology mainly uses x, y and neutron media. Most of the tests use these three mesons. The energy in the transmission process of the three will gradually weaken, so as to judge whether there are defects in the equipment after use. The corresponding technical means can be used to extract the corresponding data from the defective parts. However, this detection method also has serious defects. It may not detect equipment with a large area and complex internal structure. At the same time, radiation also has a certain degree of impact on human health. Therefore, when using radiation detection, it is necessary to take appropriate protective measures.
2.2 Ultrasonic detection technology
The main working principle of ultrasonic detection is to use the function of ultrasound to detect equipment and check whether there are some defects inside the equipment during the production process. Ultrasonic waves have a certain directionality during the detection process, so ultrasound can provide feedback to the staff through the reflected wave pattern. When the fluctuation of the wave pattern has a large gap or a large fluctuation and is discontinuous, it means that there is some damage inside the equipment. Compared with radiation detection, this method will not cause harm to the human body, and this method is more sensitive to defects, very sensitive to defects, and relatively convenient to operate, but for some complex structures, there will be detection errors.
2.3 Magnetic particle detection technology
Magnetic particle detection technology uses micro particles, that is, magnetic powder, to detect equipment. Because the manufacturing materials of most equipment are different from the magnetic resistance of magnetic powder, these magnetic powders will cause bending when detecting the inside. This type of detection is mainly used for welding joints and surface quality detection, because welding joints are relatively weak and more susceptible to corrosion. The huge workload will cause some cracks in the equipment. Since other technologies cannot better present the problems when detecting these places, magnetic particle detection technology can be used to supplement. Magnetic particle detection technology can intuitively show the position of the detection object, and the sensitivity of this technology is relatively high. It can also detect the welding edge. The detection function is relatively complete and the operation is simple. However, this detection method is only applicable to magnetic parts. For non-magnetic materials, it is impossible to perform a full range of detection in some places.
2.4 Penetration detection technology
Penetrating detection technology is a relatively simple detection method compared to other methods. It uses penetration to detect the equipment and applies the penetrant liquid to the surface of the part to be detected. If the part is damaged or cracked, the penetrant liquid will flow into it, and it can be intuitively observed whether the parts in the equipment are damaged. This method is the simplest operation of these detection methods, and it also saves a lot of money. The detection of uneven parts can best reflect the advantages of this detection method, but this method can only detect the surface and cannot detect internal damage.
2.5 TOFD detection technology
The Chinese name of TOFD detection technology is time-of-flight diffraction ultrasonic detection. It is a new detection technology in recent years and is currently being developed in various industries. During TOFD detection, discontinuous defects produce wave-like conversions and convert them into diffraction waves. This detection technology covers a large range during the detection process. It mainly determines whether the components under detection are damaged by the time difference of the diffraction signal’s flight, which has nothing to do with the floating of the wave graph. Compared with other technologies, the measurement data of this test technology is more accurate, and the defects are displayed through images. The amount of information is large but it is easier to save, and the ability to detect defects is also relatively strong. It is mainly used for workpiece detection greater than 12mm. It has the function of ray detection technology, but it is not radioactive, and will gradually replace ray detection technology.
3 Ways to efficiently apply nondestructive testing technology in coal mine equipment maintenance
3.1 Comprehensive application of multiple testing technologies
In the inspection of coal mine machinery and equipment, maintenance personnel need to fully understand the application advantages and application defects of various testing technologies when using nondestructive testing technology. If there are multiple technical application conditions in the inspection work, then maintenance personnel can also choose to use multiple testing technologies in combination to achieve the effect of combining the application advantages of multiple technologies. In this way, not only can the inspection speed be improved, but the inspection information obtained will also be more comprehensive, and finally more accurate inspection results will be obtained.
3.2 Seize the good opportunity for inspection
Before using nondestructive testing technology, maintenance personnel need to have a clear understanding of the inspection target, and then choose the appropriate inspection technology based on this. For example, if maintenance personnel need to use ultrasonic flaw detection technology, then if the forgings are not processed in advance, the technical application conditions will not have strong coupling, and the surface of the mechanical equipment will be relatively rough, and the application effect of the technology will not be ideal in the end. However, if the maintenance personnel use ultrasonic flaw detection technology after drilling and fine grinding the mechanical equipment, they can not only clearly understand the actual damage inside the mechanical equipment, but also avoid secondary damage to the mechanical equipment during the maintenance process. Therefore, it can be seen that when using non-destructive testing technology, maintenance personnel need to accurately grasp the timing of using maintenance technology, and try to carry out equipment inspection work between rough processing and fine processing. In addition, when the maintenance personnel are testing the types of steel, they also need to weld the test objects, and the inspection can only be carried out after the welding is completed and completely cooled.
3.3 Scientific selection of non-destructive testing technology
Although non-destructive testing technology has more application advantages than traditional testing technology, this type of technology is not all-purpose. If maintenance personnel want to make full use of the application value of non-destructive testing technology, they need to conduct a comprehensive analysis of the material, structure and size of the mechanical equipment before using it, and then select the appropriate non-destructive testing technology based on this. When the scientific application of nondestructive testing technology is guaranteed, not only can maintenance and testing work be carried out in an orderly manner, but also the mechanical equipment will not be damaged again during the testing process.
4 Support measures for the application of nondestructive testing technology in the maintenance of coal mine mechanical equipment
4.1 Improve the professional quality of testing personnel
If the mechanical equipment is not tested after use, the defects of the mechanical equipment will inevitably bring huge losses when used again. Therefore, the relevant testing personnel must improve their professional quality. It is necessary to conduct corresponding quality inspections on the mechanical equipment after use in a timely manner, and at the same time strengthen their own testing capabilities. Enterprises have higher requirements for relevant technical personnel. The state should introduce some relevant measures to provide advanced technology and rewards, and strengthen the safety awareness and sense of responsibility of technical personnel. Relevant departments should hire relevant professionals to provide technical training and lectures for the staff of the testing department, conduct technical inspections on the testing personnel of the department, provide free learning and training opportunities for the staff, and introduce some reward and punishment measures to strengthen the management of the testing personnel, and at the same time provide security facilities for the safety of the testing personnel. Finally, enterprises can regularly organize training for testing personnel, and the training content includes not only the learning of non-destructive testing technology application methods, but also the mastery of professional knowledge involved in non-destructive testing technology. With the development of training activities, enterprises can also regularly assess testing personnel in combination with training content. Through assessment, we can not only see the improvement of testing personnel’s ability more intuitively, but also constantly stimulate the enthusiasm of testing personnel to participate in training activities.
4.2 Improve the monitoring work management system
There have been corresponding improvements in testing technology and related personnel. Therefore, more attention should be paid to the work management system of mechanical equipment. Establish a good management system, increase the management and requirements of relevant technical personnel, formulate different management for people in different positions, and publicize the importance of mechanical equipment testing to workers and the harm caused by not conducting testing in time. Because there will be many accidents during the testing process, it is necessary to formulate corresponding treatment plans and formulate corresponding protection measures for the staff. Each different mechanical equipment has different production standards. Therefore, it is necessary to clarify the production process and improve the skills of the staff. At the same time, it is also necessary to survey different environments and select testing plans according to the materials of the mechanical equipment.
4.3 Create and improve the diagnostic indicators of coal mine machinery and equipment
In the process of non-destructive testing of mechanical equipment, maintenance personnel need to test relatively more parts. If the enterprise does not formulate a complete diagnostic indicator for coal mine machinery and equipment in advance, it will not only make the diagnosis more difficult, but also the diagnostic efficiency will be difficult to guarantee. Based on this, what the enterprise needs to do is to fully implement the principle of focusing on commonality and supplemented by differences, and establish a complete diagnostic indicator for mechanical equipment. Since in the process of coal mining, workers need to use a variety of mechanical equipment, and the functions of different mechanical equipment themselves are quite different. Only after the enterprise clarifies the differences between various types of equipment can maintenance personnel establish and implement accurate equipment diagnosis plans. For example, for the conveying equipment and screening equipment at the coal mining site, the difference between the two is quite obvious. And maintenance personnel need to clearly distinguish the diagnostic indicators of the two equipment to ensure the accuracy of the diagnostic indicators. Finally, when formulating equipment diagnostic indicators, enterprises also need to start from the strength of the enterprise itself and the overall situation of the current coal mine to ensure that the final diagnostic indicators can better serve the maintenance work of the enterprise’s coal mine machinery and equipment.
4.4 Commonly used and efficient coal mine machinery maintenance technology
For coal mine machinery, the hydraulic columns and picks used for excavation are prone to damage during long-term work. Long-term wear of these parts leads to metal fatigue and failure. Therefore, we usually use laser cladding technology to remanufacture these parts. Laser cladding allows metal powder to form a metallurgical bonding layer on the surface of the substrate, increasing the strength to 5-10 times that of the original. Repairing parts with laser cladding technology not only greatly improves their service life, but also saves huge costs for enterprises. It is a near-perfect metal remanufacturing and repair technology.
5 Conclusion
In short, maintenance personnel need to strengthen the application of non-destructive testing technology in the process of carrying out maintenance and inspection work on coal mine machinery and equipment, and at the same time select appropriate non-destructive testing technology for use in combination with actual conditions. In addition, maintenance personnel must also find the actual inspection to ensure the scientific and comprehensive application of non-destructive testing technology. In this way, not only can the application value of non-destructive testing technology be maximized, but also a relatively ideal maintenance and inspection effect can be achieved.