In our Executive Throwbaback, we take a look at Fred C. Bond. Born on June 10, 1899, Bond who died on January 23, 1977 was an American Mining Engineer, a Graduate and former Professor of the Colorado School of Mines. He worked in the mining equipment and ore milling equipment business of Allis-Chalmers from 1930 to 1964 and made an enormous impact on the science of ore crushing and grinding with his development of the Bond Theory of Comminution and Work Index. For many years, it has been and is still being used standard method for calculating the energy input necessary for crushing rock in blasting and mineral processing.
During his distinguished career, Bond published over 100 technical papers on crushing and other mining metallurgical subjects. His reputation as an expert in metallurgy is known throughout the world of mineral processing and his services were in great demand. He worked for mining companies in Honduras, Bolivia, Australia, Mexico, and in the U.S : in Arizona, Colorado, Montana, Tennessee and Wisconsin. He was employed for 45 years by Allis-Chalmers where he served in various positions including Manager of the Ore Dressing Department.
Bond Work Index
In the 1930’s through early 1950’s, Bond developed a new theory of comminution that introduced an index, called the ‘Bond Work Index’, which relates power consumption in crushing and grinding to the feed and product size distribution. His theory and index were introduced in a widely cited 1952 journal article Bond called his theory the “third theory of comminution”, counting those of Peter von Rittinger and Friedrich Kick as the first and second.
This term and the terminology of “laws of comminution”, as in “Rittinger’s law”, “Kick’s law”, and “Bond’s law”, are sometimes used in the field, along with those of subsequent researchers including Walker and Hukki. Whereas Rittinger’s theory held that the work done in breaking rock is proportional to the new surface area produced (that is, inversely proportional to the diameter of the product particles), and Kick’s theory held that the work done is directly proportional to the reduction ratio (ratio of feed particle diameter to product particle diameter), Bond’s theory held that the work varies inversely as the square root of the product particle diameters. Bond’s theory and index brought a greater measure of openness to the calculations for selecting the type, size, and power ratings for ore milling equipment.
Bond was inducted with its first class into the National Mining Hall of Fame posthumously in 1988, and received a Distinguished Achievement Medal by his Alma Mater, the Colorado School of Mines, in 1952. He received the 1965 AIME Robert H. Richards Award ” for major contributions to increased knowledge of crushing and grinding processes and for achievement in industrial application of this knowledge to advancement of the milling industry.”