Mine explosion-proof motor damage cause analysis

Cause analysis of 2019 - mine motor damage 04 - 08 abstract: through the analysis of the coal mine field use moters, in combination with the practical situation of the mine, puts forward several common reason and analysis, in order to prevent mine explosion-proof motor damage, ensure that can be drawn lessons from for the normal operation of the experience. Key words: mine motor; Power off protection; 1, an overview of the motor protection measures in the process of coal mine production occupies an important position, directly affect the coal mine safety production. Look from the scene, motor damage percentage has the following characteristics: less ground and underground; Much less fixed equipment, mining area burn out. The service life of the motor and the motor temperature rise, the use of the environment and has a direct relationship between degree of maintenance conditions. Field experience shows that as long as the motor use reasonably and maintain proper, in the operation of overtemperature, overload, its service life is long; On the other hand, the service life of the motor can be shorten greatly. Common reasons for 2 2, motor damage. 1 motor working voltage instability in accordance with the relevant standards, shall be the rated voltage of the motor working voltage range + 10% ~ - 5%. If the motor running in voltage instability environment for long time, will damage the motor. Example: after underground mining area transformer operation, did not check the secondary voltage into the motor running. 2. 2, motor open phase running if electric machine long time lack of phase operation, such burning motor. The common cause of motor open phase are: 1) Connection when the bolt is not tight, long running cause fever wire, the final point connection burn out; 2) Control switch fuse rated current don't match, the current increases when a phase burn out; 3) Control switch in phase one phase contact contact undesirable, fever burn out. 2. 3, if the electric machine long time overload running motor is overload for a long time running, can also lead to the excessive heat of the motor and burn out. Example: 1) Transportation machinery design is unreasonable, electric captain time overload transportation or overloading starting; 2) Line drop too much, make the motor run under voltage, load start and start time is long, large current; 2. 4, Y/delta motor wiring wrong if wrong, star of the motor, the triangle can cause the motor burn out. This phenomenon is caused by the electrical installation is not carefully check. 2. 5, if motor rotor 'sweep don' motor bearing wear, can make into the motor rotor and stator, namely 'sweep hall, that will also lead to motor damage. Common reasons are: 1) Oil is not up to standard, motor rotates overflow; 2) Failed to timely oil bearing oil shortage, bearing clearance is too large due to wear and tear. 2. 6, motor cooling motor temperature rise in addition to the associated with the current, also had a lot to do with environment temperature, heat loss itself. Mining transportation equipment with motor has often been buried coal or waste rock pressure, cause the clogging in motor blades damage or duct, if not replace or clean up in time, will cause the motor is poor ventilation or heat. Result in motor overheating and damage. 2. 7, single-phase motor winding grounding when any of the motor phase winding insulation damage, will make the rest of the two phase winding of voltage into the line voltage, good winding insulation breakdown due to voltage rise, interphase short circuit caused by burning motor. 2. After 8, motor winding motor be affected with damp be affected with damp be affected with damp be affected with damp, the insulation resistance is reduced greatly. After electrify insulation breakdown caused by short circuit and burning motor. Common causes of be affected with damp be affected with damp, due to relatively humid, if motor in underground store or use for a long time, and no water spray water be affected with damp be affected with damp, moisture-proof measures can make motor. 3, summarize, in short, in order to guarantee the normal operation of the motor, to ensure normal production of coal mine safety, for the cause of damage to the motor, can be targeted measures, including the prevention of motor overheating, overload, single phase to ground, short phase operation, etc; To strengthen the maintenance of the motor; Practice the overhaul package mechanism; Enhance workers sense of responsibility; Strengthening the management of mechanical and electrical equipment quality standardization; Do the safety technical training of drivers and maintenance staff work. Believe that after the above measures, can greatly reduce coal mine motor damage, to ensure the safety of mine production, and improve the economic benefit of coal mine. References [ 1] Tianjin electric drive design research institute of electric drive automation technical manual mechanical industry press, 2009 [ 2] Ma Shenxing electric transmission and application of the aviation industry press, 1993 ( Graphic)