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Tolerance design has become a very sensitive and important issue in product and process development because of increasing demand for quality products and the growing requirements for automation in manufacturing. It is an interactive process between design and manufacturing decision making. A systematic approach to tolerance design involves repeated computation following two alternate steps: (a) tolerance analysis and (b) tolerance synthesis. The focus of this part of the paper is on tolerance analysis. A brief discussion on the relevant background terminology has been presented. Details of research carried out and theories developed over the decades on different aspects of tolerance analysis have been discussed.

Tolerance design has become a very sensitive and important issue in product and process development because of increasing demand for quality products and the growing requirements for automation in manufacturing. It is an interactive process between design and manufacturing decision making. A systematic approach to tolerance design involves repeated computation following two alternate approaches, tolerance analysis and tolerance synthesis. A detailed discussion on tolerance analysis has been presented in Part 1 of this paper. The focus of this part of the paper is on tolerance synthesis, i.e. the allocation of assembly tolerance among the individual dimensions. A brief discussion on the relevant background terminology has been presented. Details of research carried out and theories developed over the decades on different aspects of tolerance synthesis have been discussed.

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The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel-dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A highspeed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.