Author

Brijes Mishra

Date of Graduation

2007

Document Type

Dissertation/Thesis

Abstract

Analysis of the cutting process of a continuous miner in a coal mine requires a tedious experimental set up. But with the advance of modern computers, such complex system can be simulated using numerical modeling. It is the goal of this dissertation to use finite element analysis to investigate the effect of bit design and drum design on cutting. The study involved the use of a miniature cutting drum and three dimensional finite element models to achieve the goal. The miniature cutting drum named as Automated Rotary Coal Cutting Simulator (ARCCS) was developed to analyze the cutting process. The cutting drum has undergone four different versions. In this study drum version-three and drum version-four were analyzed. Numerical model was developed incorporating the geometry of drum version-four. Yu (2005) analyzed the performance of drum version-three. For analyzing the effect of bit design three different bits were used, (1) Khair bit; (2) Kennametal bit-A; and (3) Kennametal bit-B. Numerical model of drum version four was used to analyze the effect of bit design. These three different bits were compared based on the forces developed on the bit and specific energy consumed in a multiple bit cutting analysis. Single bit model was used to investigate the development of heat on the bit. For analyzing the drum geometry the results obtained from the numerical modeling analysis of the drum version-four was compared with the results obtained by drum version-three analysis by Yu (2005). The parameters used for comparison were forces developed on the bits and specific energy. In order to make the modeling results more practical and meaningful the results obtained from the ARCCS was used to carry experimental analysis of the cutting process. The comparison parameters were forces developed while cutting, specific energy and respirable dust generation. The drum version four analyses was compared with the results obtained from the drum version-three analysis carried out by Rizwan (2002). Finally the bits were tested in a coal mine on a continuous miner for different cut of coal. The bit performance was compared on the basis of (1) wear of bit; (2) dust produced; and (3) power consumption. In conclusion the modeling and experimental results indicated that the change in the size and shape of the bit tip increased the performance of the cutting system. Heat influenced zone on the bits were identified and were compared with the worn bits. The cutting performance of the Khair bit was better than bits used for comparison. The new drum version-four showed better cutting performance than its earlier version.

Share

COinS