Design And Application Of Belt Conveyor In Large Capacity And Complex Working Condition Of AnTaiBao Open Pit Mine

Belt conveyor is the main equipment for bulk material transportation at present,which has the advantages of continuous transportation,high degree of automation,low operating cost and environmental protection,etc.With the development of technology,it is more and more widely used,long distance and large transportation volume are its important development direction.Antaibao opencut coal mine is one of the five open pit mines in China,in its raw coal transportation system,the length of 903 belt conveyor is2556 m,the height difference between head and tail is about-114.5 m,and the transportation capacity is 4500 t/h,such a large transportation volume and height is the first in China.There are many operating conditions such as motor drive,power generation braking and so on,and the inertia of material and conveyor belt is very large,how to realize its safe and stable operation is a challenging research direction.This paper starts with the calculation of belt conveyor under large traffic volume and complex working conditions,the iterative calculation method is used to calculate the conveyor belt tension under full operating conditions and full friction resistance(0.012 ? 0.03),according to the calculation results,the equipment selection and three-dimensional modeling are carried out;the braking,multi motor power balance and start stop under heavy load conditions are analyzed,and combined with the actual operation of the project,the factors affecting the simulated friction coefficient are analyzed,the actual effect of multi motor power balance strategy is evaluated,puts forward the safe starting strategy of belt conveyor under heavy load and the measures to prevent braking from slipping.The main conclusions of this paper are as follows:(1)The simulated friction coefficient of belt conveyor under large volume and complex working conditions is 0.016 ? 0.027.(2)The "holding brake start" mode is adopted,so that before the brake is fully released,the frequency converter can enter the stable and controllable frequency section,which effectively prevents the heavy load start-up and car sliding accident.(3)Based on the traditional hydraulic brake,the real-time comparison between the output speed detection at the driving end and the belt surface speed detection at the running end can effectively prevent the braking slip and greatly improve the safety and reliability of the braking link.The relevant theories of this paper have been verified by practical engineering for more than two years,and successfully solved the problem that the belt conveyor with large traffic volume and complex working conditions,especially with downward working conditions,is easy to slip and slip in the starting and braking links.Compared with similar projects in China,it has been improved in the safe operation of the system,which provides a reliable reference for subsequent similar projects.