Evaluating the Power Consumption in Carbonate Rock Sawing Process by Using FDAHP and TOPSIS Techniques

Abstract

The prediction of rock sawability is important in the cost estimation and the planning of the stone plants. An accurate estimation of rock sawability helps to make the planning of the rock sawing projects more efficient. Rock sawability depends on non-controlled parameters related to rock characteristics and controlled parameters related to properties of cutting tools and equipment. In the same working conditions, the sawing process and its results are strongly affected by mineralogical and mechanical properties of rock. Up to now, many studies have been done on the relations between sawability and rock characteristics in stone processing. Norling (1971) correlated sawability with petrographic properties and concluded that grain size was more relevant to sawability than the quartz content. Burgess (1978) proposed a regression model for sawability, which was based on mineralogical composition, hardness, grain size and abrasion resistance. Vaya and Vikram (1983) found a fairly good correlation between the Brinell hardness test and diamond sawing rates. However, the variables involved were so many that they believed no mathematical solution would be possible. They also considered the Specific Energy (SE) concept, in conjunction with mineralogy, to give a better understanding of the sawing responses of various rock types. Ertingshausen (1985) investigated the power requirements during cutting of Colombo Red granite in up-cutting and down-cutting modes. He found out that the required power was less for the upcutting mode when the cutting depth was below 20–25 mm. For deeper cuts, however, the power consumption was less for the downcutting mode. Wright and Cassapi (1985) tried to correlate the petrographic analysis and physical properties with sawing results. The research indicated cutting forces to have the closest correlation. Birle et al. (1986) presented similar work in 1986, but again considered only blade life as the criterion on which a ranking system should be based. Hausberger (1989) concluded that an actual sawing test was the most reliable method for determining the machinability of a rock type. He observed that the higher proportion of minerals with well defined cleavage planes helps the cutting to be easier. Jennings and Wright (1989) gave an overall assessment of the major factors which affect saw blade performance. They found out that hard materials usually require a smaller size diamond than do softer stones because the load per particle is not sufficiently high and greater clearance is required for swarf.