Quality-control, selection and specification of refractories - an Indian overview

Quality control in the refractory manufacturing starts with the raw materials. Generally the materials used in refractory production are naturally available and varying in composition. In practice raw materials are suitably graded, stock pile and blended in order to obtain uniform composition. Thus quality control plays an important role at each and every stage in the refractory production. Selection of refractory for a particular application depends on different physical and chemical parameters which are discussed in this paper but the final selection should be made taking into consideration of the best available refractory with respect to the operating conditions and the cost of such a refractory. Specifications of the refractory are only indicative for selection of a particular refractory. Moreover, the specifications should be periodically revised in view of the experience gained in the refractory manufacturing as well as in the applications. Set of operating conditions should be made for both the manufacturers and users of refractories in order to obtain most optimum advantages by using refractory as a material of construction for any high temperature application