Researching Of Safety On Striking And Frictional Sparks Of Material For Coal Mine

During the production in coal mines, the instruments .equipments and apparatus are always gotten shock, friction and press, thus causing high temperature hot mark and spark. Under specific conditions, high marks and sparks could cause gas and dust explosion in coal mines. So friction spark is one of the potential ignition source which causes gas explosions in coal mines.In this paper , tribology , heat transfer , materials and blasting theory are used to study and analysis the causes of friction, friction mechanism and principle of head caused by friction , chemical reaction caused during the metal materials friction ,mathematical model of heat marks caused by friction and spark temperature field heat transfer. the ignition principle of gas and dust in underground coal mines, factors affected by mental material friction spark temperature .meanwhile the these theory are used to study the safety issue of mental material friction spark.When the mental material impact each other , it will cause friction spark to ignite gas, after analysis this process , we learned the essential of this process is the energy transfer process. five stages which are successive are passed during this process. . if any link is broken, it will stop the energy transmission .Through the experiments , it is shown that impact height, impact angle, the weight of impact material and environment condition will affect ignition status caused by friction spark . we also found that the chemical property of mental material itself are one of main ignition factors caused by friction. Especially the alloy material such as Mg,Sr have very higher ignition rate. So mental material with active chemical property used in coal mine should be restricted.Friction surface by the impact attachments will bring friction spark safety big uncertainty. The existence of coal particles play the role of catalyze to oxidation of metallic materials. So when methane and coal dust coexist under the environment, is very important to test friction spark safetyThrough theory analysis and test study , combining former research achievements and production practice . the preventing measure are proposed to friction spark . own ideas and suggestions are put forward in the study of friction spark safety.