1、英文原文 Research of Fire Hazard Critical Guidelines of Mine Use Belt Conveyor and Automatic Fighting Fire System Congli Zhang, QichangDuan， Jinling Pan and Li Xin Rockwell Automation Lab, College of Automation ChongqingUniversity Chongqing, China Xin Li The Key Lab of High Voltage Engineering and Elect
2、rical New Technology ChongqingUniversityChongqing. Abstract:The fire hazard critical guidelines of coalmine use belt conveyor were researched, and the early parameters of fire hazard were tested. Based on experiments, relative sensors and a fire detecting system were developed, which made up of sens
3、ors and accessories. Again water spray fighting fire technology was researched, and effects of fighting fire were tested and inspected by simulation in experimental roadway. keywords:Belt conveyor, Fire hazard, Sensor . INTRODUCTION At present, mine use belt in China is more than 4,000 km, and 300km
4、 more belt is added in coalmine every year. Once these belt conveyors get fire, the influence and destroy are far worse than coal seam fires and mined-empty places fires. So, the former Coal Ministry prescribe that, All the belt conveyor must furnish detective devices preventing get fire under frict
5、ion. The device should include temperature sensor, smog sensor, work state sensor etc. When the belt conveyor gets fire, the device can stop the machine and alarm, at the same time, the device should start automatic fighting devices. To adapt the request, we researched the fire critical guidelines o
6、f belt conveyor used in coalmine underground. We analyzed critical guidelines of fire hazard, and confirmed main parameters of fire detection. Then we developed differential-speed sensor and temperature sensor for coalmine. Using these sensors as basic unit, with some other corollary equipments, we
7、worked out mine belt conveyor fire hazard automatic detecting system (System for short below). This System can detect belt conveyor, alarm when dangerous, stop machines when power-off, and it has automatic water spray fighting fire function etc. The system can form water curtain belt to isolate fire
8、 in roadway. Simulating in test roadway show that the System has excellent effect, and it had been popularized in China Coal Industry. . THE RESEARCH OF CRITICAL GUIDELINES OF BELT CONVEYOR FIRE HAZARD Research indicated out that the majority belt conveyor fires are caused by belt skid, friction cau
9、sing temperature raise. So we made simulating experiment of belt skid and friction. The conveyor in this experiment is special belt conveyor for underground coalmine. Electric mutor rated output is 22kW, rotate speed is 46.2r/min, and driving roller diameter is 400mm. The belt used in this experimen
10、t is normal mine use belt, belt width is 0.8m and thickness is 0.01m. When test, one end of the belt is fixed. After wrapped the roller, force meter pulls the other end of the belt tightly. The angle of surround of belt on rollers above and below is 210Fig. 1 is the experiment device. When test, det
11、ecting temperature of neighborhood (7mm-10mm to roller surface) of navel of surround angle of belt driving rollers. Fig. 2 is temperature curve, at the same time, detecting CO, CO2, CH4, (Table l), and observe smog release and smog sensor work states. 471652 3 Fig.1 Belt skid friction test device sc
12、hematic diagram 1 denotes 1# testing temperamre point； 2,3,4 denote 2#, 3#， 4# testing tempemme point respectively； 5-belt； 6-driving roller； 7- force meter The experiment processed in condition that air speed is 1.6m/s and quantity of airflow is 970m3/min. In belt full skid condition, test lasts un
13、til fluxing. Again, we inspected 4# detecting point temperature raise in different condition, forward and backward for air, under air speed 3.5m/s condition, 4# point temperature curve shown in Fig. 3. Test results: 1) In full skid condition, the highest temperature area is at the center of unwrappe
14、d zone of the roller. The nearer to the surface of the roller, the higher the temperature is. Difference in temperature is 5 in field 7mm-l0mm to the surface of the roller. The temperature sensor can be located in the navel of unwrapped zone, it is 10mm to the surface of the roller； 2) When belt ful
15、l skid keeping for 2 min, smog can be observed, and empyreuma can be smelled. Up to 23min, smog sensor begins to alarm. So it is necessary to take smog concentration as critical guidelines of fighting fires. Smog Sensors can be installed the place, which is 3m-5m to the driving roller forward air, 2.0m above the
