Analysis of maintenance methods of coal mine mechanical and electrical equipment

- Nov 29, 2019-

l mine mechanical and electrical equipment

I. Types and consequences of failures in the use of mechanical and electrical equipment

Damage type failure: such as fracture, crack, pitting, ablation, deformation, strain, crack, indentation, etc.

Degraded failure: aging, deterioration, flaking, abnormal wear, etc.

Release-type failure: looseness, shedding, etc.

Offset faults: too high or too low pressure, out of stroke, too large or too small clearance, interference, etc.

Blocking and leakage type faults: blockage, water leakage, air leakage, oil leakage, etc. 1.6 Functional failure or functional failure mode: functional failure, performance degradation, overheating, etc.

Second, failure cause analysis and steps

The purpose of fault analysis is not only to identify the nature of the fault and find the cause of the fault, but also to identify the fault mechanism clearly and propose effective improvement measures to prevent repeated faults. Through failure analysis, find the real cause of the failure, and take measures from design, material selection, manufacturing, assembly adjustment, use and maintenance to improve the reliability of mechanical products.

When analyzing a fault, it usually starts from the fault phenomenon and finds the cause and fault mechanism through the fault phenomenon. Due to the limitations of the site conditions, the observed or measured failure phenomenon may be systematic, such as the centrifugal pump does not absorb water; it may also be a component, such as the centrifugal pump's packing is too hot; or it may be a part, Such as the surface of the shaft or sleeve is damaged. Therefore, for different levels of the product structure, the failure modes have a causal relationship with each other.

Failure cause analysis is a comprehensive subject that involves system analysis, structural analysis, test analysis, and knowledge about various subjects such as fatigue, fracture, wear, and corrosion.

The failure analysis mainly includes the following steps:

(1) On-site investigation mainly includes collecting background data and conditions of use such as the time, environment, and sequence of the fault; video or photography of the fault site; collecting and organizing the main historical data of the faulty parts such as design drawings, operating specifications, acceptance reports, and fault conditions Records and maintenance reports, etc .; carry out preliminary inspection, identification, storage and cleaning of faulty parts.

(2) Analyze and determine the cause and mechanism of the failure. It mainly includes inspection and analysis of nondestructive inspection, performance test, and macro and micro inspection of fractures; necessary theoretical analysis and calculations such as strength, fatigue, fracture mechanics analysis and calculation; etc .; preliminary determination of the cause and mechanism of failure.

(3) Analysis conclusion. When each failure analysis work reaches a certain stage or the end of the test work, all the obtained information, investigation records, testimony and test data must be carried out according to whether there are any problems in design, materials, manufacturing, and use. Focus on induction, comprehensive analysis and judgment processing, and come up with a report with clear conclusions and recommendations. On the one hand, it is to improve work, accumulate information and exchange experiences; on the other hand, it also provides the basis for claims and legal arbitration.

Third, the general maintenance of coal mine mechanical and electrical equipment

Main points of equipment maintenance and repair

Correctly handle the maintenance relationship of prevention-based plan. Prevention is mainly through observing and testing the use of electromechanical equipment, grasping the wear and tear of the equipment, and paying attention to daily maintenance and repair. Eliminate hidden troubles of electromechanical equipment in time. When the wear reaches a certain level, regular or timely maintenance is required, and there can be no delay. Therefore, prevention must be combined with planned maintenance.

Correctly handle the relationship between production and maintenance. Equipment maintenance requires a certain amount of manpower, material resources and time. Some coal mines often neglect the maintenance work when the production tasks are heavy, and the electromechanical equipment becomes ill and causes accidents. Seriously affect production, safety and schedule.

Correctly handle the relationship between daily maintenance and regular professional repairs. The daily maintenance work is generally performed by an employee in the use of electromechanical equipment. It must be implemented to the head through the post responsibility system. Professional maintenance is the responsibility of the professional repair company. Planned inspections and repairs must be effectively combined to avoid one. "Fault 'artifacts occur.

Concerning the specific work of mechanical and electrical equipment maintenance, the daily inspection content, requirements and precautions should be formulated from the structure, performance and characteristics of the equipment. Inspection of electromechanical equipment can be divided into daily inspection and regular inspection. The inspection methods can be divided into sensory, empirical inspections, and scientific methods such as instrumentation. The major repairs, intermediate repairs, and minor repairs of electromechanical equipment must be performed in steps according to the specific conditions of the electromechanical equipment.

Fourth, the improvement of coal mine mechanical and electrical equipment maintenance methods

Intangible wear and tear of mechanical and electrical equipment innovation means that the new mechanical and electrical equipment caused the depreciation of the original mechanical and electrical equipment. First, the price of new electromechanical equipment caused the depreciation of the same and similar electromechanical equipment. Second, the emergence of new, better-performing and more complete equipment reduced the effectiveness and depreciation of the original equipment.

Technical transformation of electromechanical equipment is a partial change to the structure of electromechanical equipment, thereby innovating the performance of equipment and improving production efficiency. Technical transformation is the objective requirement of production development and technological progress. According to the current aging of mechanical and electrical equipment of coal enterprises in China, and the low level of science and technology, technical transformation requires comprehensive and technical, safety, economic, and environmental comparison and demonstration of the project. Conduct a possibility survey to choose the best solution.

Technical update of electromechanical equipment. The technical update of electromechanical equipment is to replace the old electromechanical equipment with new electromechanical equipment. The update of electromechanical equipment does not only refer to the replacement of electromechanical equipment of the same model and type. The main thing is to replace the old equipment with new equipment with higher performance and more advanced, so that the production is based on advanced technology and foundation. Therefore, technological updates do not necessarily wait until the electromechanical equipment wears out until it has completely lost its use value. Instead, it is economically uneconomical to continue using the old electromechanical equipment when new equipment with better performance and higher efficiency appears. As long as the conditions are met, the equipment will be updated in time to achieve complete technological innovation.

In short, with the construction of large-scale coal bases in China and the technological transformation of old mining areas, today's coal mine production is farewell to the extensive and labor-intensive production methods of the past. Large-scale electromechanical-hydraulic integrated equipment is widely used in all aspects of coal mine production. , Change the traditional single simple equipment maintenance management mode, apply advanced maintenance ideas and technology to equipment maintenance, can minimize equipment failure rate and additional depreciation rate and equipment maintenance costs, and the equipment throughout the life cycle Maximum availability and reliability.