Mill Liner Handler
Rod Mill Grinding
A detailed experimental study of breakage kinetics in a batch rod mill indicates that while the system is inherently nonlinear, the feed disappearance kinetics for the finer sizes and the coarser sizes at high holdups is well represented by first-order behavior. The set of breakage distribution functions was found to be normalizable and independent of […]
Ni-Hard Grinding Balls
Through a cooperative agreement, the Carondolet Foundry Co. of St. Louis, Mo., supplied 1,000 pounds of 2-inch Ni-hard balls for comparison with balls of other composition. Ni-hard balls are said to contain 2.5 to 6 percent nickel and 0.5 to 1.5 percent chromium. They have a Brinell hardness of 548. The company also furnished a […]
Grinding with Pebbles VS Steel Balls
Operators in the metallics industry, sometimes forget that pebble mills are an important factor in fine grinding. However, pebble mills are not extinct, as is shown by reference to a recent paper on ore milling, wherein it was shown that five of the 44 so-called “ball” mills mentioned actually were pebble mills. If the nonmetallics […]
Why use Different Size Balls in a Mill
Several years ago, Davis assumed that the rate of wear of the different sizes of balls in a ball mill was directly proportional to the weight of each ball, and he evolved a formula for calculating a balanced charge. Operators have used this formula when purchasing balls for a new mill or when reloading an […]
Ball Mill Diameter vs Length Compared Efficiency
Operators may rightly ask how much reliance should be placed on laboratory ball milling when they are using mills so much larger. This question was foremost in the earliest work at Rolla; in fact, in the beginning more attention was given to plant tests than to laboratory tests. The operators had calculated their results in […]
Grinding Efficiency of Ball Chips VS new Balls Compared
Battered Reject Balls and New Spherical Balls Compared: Operators are sometimes at a loss to know when a mill should be dumped to discard the worn and battered balls. Similarly, the present authors found an unknown variable when they compared the laboratory work of a new grinding medium with the plant performance of media, some […]
Grinding SLUGS vs Grinding Balls
Tetrahedrons and Spherical Balls Compared: An interested operator furnished 1,000 pounds of tetrahedrons for comparison with spherical balls. The tetrahedrons were all about the same size and the average weight of each was the same as for a 1 3/8- inch spherical ball. Four pairs of tests with tetrahedrons and round balls, respectively, are shown in […]
Sillimanite Balls
A stock of 300 pounds of 1 5/8-inch sillimanite balls was donated by the Champion Spark Plug Co. for grinding tests. They were true spheres, white, and all about the same size. Although native sillimanite has a density of 3.2, the artificial product had a density of only 2.56, this being the lowest density included […]
Dry Grinding Ball Load Calculation
Selection of Volume of Ball Loads in Continuous Dry Open Circuit Grinding: The tests reported in tables 19 and 20 were made in cooperation with a large cement-manufacturing company that wished to obtain more grinding for the power expended. The ball load in its clinker- grinding mills was 18 percent of the mill volume and the […]