Study On The Delay Precision Of The Short Interval Coal Mine Delay Electric Detonator

With the continues innovations of blasting technology,the quality of the blasting equipment requirements are also getting higher and higher. Coal mine millisecond delay electric detonator is an important part of blasting equipment,its delay precision will directly affect the safety of the coal mine blasting.This topic mainly study the delay precision of the short interval coal mine millisecond delay electric detonator.According to oxygen balance and combustion theory of delay composition for study on the formulation and mixed-way design of Si/PbsO4delay composition,components of delay composition will be to grinder the smaller particle size by SC-H vertical high-speed grinder, seconds test of the lead delay element of nonel detonators haven’t explosive based on photoelectric measurement system for testing its delay time and delay precision.Testing the delay time of delay element stored before and after for testing storage stability of delay time and delay precision.By mie scattering theory, have done the particle size analysis test for Si/Pb3O4delay composition stored before and after.Through the experimental study,draws the following conclusions:First,finer granularity can be achieved in a relatively short period of time by SC-H vertical high-speed grinder,for example,after grinding three hours,the particle size D50of the second delay composition is0.859micron;Second,the photoelectric testing system can be accurately measured the delay time of delay element,reduced material loss from delay elements were assembled electric detonator;Third,through the experimental test results,I have got the corresponding delay time by designing the formula of delay composition and changing the cutting length of delay body;Fourth,the delay compositions which have been milled by SC-H vertical high-speed grinder have stable combustion rate and higher delay precision;Fifth,from grain size analsis report can be concluded that particles of delay composition which have been stored are larger than before,and its specific surface area has reduced,and the different agents have changed differently.Sixth,the delay elements have been stored after six months,both of the delay time and the delay precision have changed,the delay precision is poor,but its ignition is still reliable.Through the above conclusion, it is concluded that SC-H vertical high-speed nanometer lapping machine is beneficial to improve the delay precision of delay medicine, so, nanometer grinding can improve the accuracy of delay medicine which is a development direction in the future.