Advanced Materials Research Vol. 619

Abstract: The influence factors of rock blasting fragmentation distribution are analyzed, 10 main influence factors are selected from these. Using the MATLAB BP neural network model system to analyze blasting fragmentation distribution of +860 level face at Yi Chun tantalum-niobium mine, successfully predicted the blasting fragmentation distribution, it is favorable to design the blasting parameters and industrial production.

Abstract: For the research on dynamical behaviors of mine hoist transmission system under strong nonlinear condition, the dynamic equation with nonlinear stiffness, nonlinear damping and external excitation is established. With the method of modified Lindstedt-Poincare, the influence of system parameters on amplitude-frequency characteristic is analyzed. Last, the complex dynamical behaviors caused by the change of excitation amplitude is studied through numerical simulation, and the evolution process from stability to chaos is described by the use of bifurcation diagram, maximum Lyapunov index figure and Poincare section graph. This provides a theoretical basis for further research of mine hoist transmission system.

Abstract: As material transmission equipment, belt conveyor is widely used in coal, electricity, machinery and other industries. This paper proposes a belt conveyor that directly driven by external-rotor PMSM, the drive-roller is the external-rotor, remove coupling, reducer and hydraulic coupling. The new drive system features low power consumption, high efficiency, minimum in size and weight, stable and noiseless action. Ensure the same transportation capacity, taking the SSJ1000/2×75 belt conveyors as object design a 100kW external-rotor PMSM direct drive belt conveyor. The analysis result shows the new PMSM direct drive belt conveyor is feasible; at last, design a water cooling system for the fever problem of the new belt conveyor.

Abstract: Parametric modeling of transition tubes were implemented based on constant cross section area assumption along the main central routes on CATIA software. The key objective of modeling these similar structures is to provide more geometric configuration options and modifications of micro channels for multi phase flow systems. The modeling processes were parameterized and analyzed by CATIA “Generative Shape Design” module with the help of “Parameters” and “Relations” functions. The surface models are all designed in circular cross sections that are constrained in two ways: one is perpendicular to the main central routes of the tube for planar transitional junction, and another is, perpendicular to the sub-branch central routes for oblique transitional junction three dimensionally. Next work is emphasized on numerical simulation and experimental investigation with these geometric structures in a multi phase flow system.

Abstract: As a set of typical mechanical and electrical integration equipment, mine hoist plays an important part in mineral mining industry known as the "mine throat". Traditional mine hoist mainly has the winding induction motor drive system, generator-dc machines and dc motor powered by the thyristor rectifier system. However, with the growing requirements of modern large mine hoist on hoisting tonnage, control performance, safety, reliability and the ratio of performance to price, the limitation of the traditional drive system emerges. If the permanent magnet synchronous motor(PMSM) is used to driven the heavy load, the speed reducer can be canceled. Thus, the performance of the system and control characteristic can be improved greatly. According to the status in this field above, this article brought forward a type of mine hoist with multi-rope friction driven by PMSM. A kind of multi branch control mode is adopted. Out of the actual needs of the project, a rated power 1300 kW of multi-rope friction mine hoist is designed and manufactured. Loss and heating of high power PMSM is studied. A kind of inner circulation air-cooled system is worked out. And good cooling effect is achieved.

Abstract: This paper introduces dynamic impact analysis as an effective technique for studying the response of horizontal vibrated conveyor with time-varying impact excitation by the falling of the scrap. A two degree-of-freedoms impact dynamic model is formulated considering the static and dynamic coulomb friction between the scrap and chute. Then the time integration algorithm was applied in the program to solve the dynamic equations. Using the proposed method, the impact effects of ideal single scrap and multiple scraps on the dynamic response of the conveyor were analyzed. Computational results reveal numerous interesting dynamic characteristics which can be used to forecast and control the vibration of the scrap and conveyor system.

Abstract: In this paper, the actual working conditions in the excavator bucket load in the mining process and foreign load has random features of Pro/E and finite element analysis software ANSYS to establish the bucket entity model, based on rock mechanics, material nonlinear analysis theoretical Construction of the soil constitutive model simulation, and the bucket of the different movement of the force, respectively bucket two main conditions the stress and displacement contours and analysis of the ultimate stress values and bucket stress characteristics is to improve the bucket force and work performance, improve safety and efficiency of the bucket work to provide a basis.

Abstract: On the basis of two pilots operating the split truck in the roadway, study control strategy of the single-pilot operating powering vehicle and flatbed walking and following straight; establish the kinematic model of the control method and field test verification; detect angles of the rod and powering vehicle、flatbed vehicle; improve the control performance of the truck, supply the theoretical and practical basis for similar products, and further corner’s following.

Abstract: To analysis the fracture mechanism and breaking location of the stick. By using ANSYS software to establish the model of excavator stick, and focus on analyzing the force changes of excavator stick in largest excavating force. By the modal analysis and transient dynamic analysis, stick stress and deformation distribution are obtained, further poses that reasonable to add the ribs, appropriate to strengthen cover thickness and the welding process of the stick will help prevent cracks. The results provide a reliable theoretical basis to improve the life of stick.