Note on the use of profile features of Swapozhnikov's plastometric curves for assessment and blending of coking coals

In an effort to utilize the Sapozhnikov's plastometric test to evaluate Indian Coking coals, the authors have brought out, in two earlier publications, the significance of the profile features of the expansion pressure curves in supplementing the indices X and Y. A third parameter called profile length (L) has been found to be successful in the grading of Indian coking coals. In this Paper results are presented of studies made on a wide cross-section of Western and Australian coals. In view of the close interplay of dilatation, shrinkage and agglutination characteristics of coal on the quantity of coke the authors propose a unitary parameter called coking quotient involving the three indices in a rational manner. The coking quotient generally agrees with the other standard tests. A novel feature of this Paper is the development of a CQ-rank relationship by which blending of several coking coals can be optimized.