Хонинговальные головки

The different types of roll mills that have been used for pastes include three-, and even five-roller mills. During the latter part of the 19th century, double-roll mills were adapted for use in the grain, ink, paint, and rubber industries, and they are still used for these purposes. Each application has specific objectives; for example, […]

Balls used in the first compartment are larger than those in the second because much larger particles must be broken. Sizing distributions vary according to clinker character­istics and whether the mill is in open or closed circuit. Some clinkers contain small, hard nodules about 10-15 mm in size that grind slowly and may enter the […]

The improvement in grinding efficiency in a conventional stirred mill, as the media became smaller, led to sand with a particle size of 0.5-0.9 mm being used as the media and the shaft speed increasing from 1,700 to 2,200 rpm. This highlighted the importance of stir­rer design to ensure that there was a uniform energy […]

Reliable initiation of the explosive decomposition of nitroglycerin was a problem from the start. Black powder safety fuses were tested but gave erratic results, so Nobel returned to a detonator that he had patented in 1867 before dynamite was invented. This was a tin capsule containing mercury fulminate that exploded when struck, and when used […]

Peter Ritter von Rittinger Peter Ritter von Rittinger was an outstanding mineral scientist whose equipment inven­tions and mathematical descriptions of unit operations established mineral processing as a modern technology (Steiner 2000; Vozar and Kunnert 1972). He was the first to pro­vide a sound mathematical basis for the physics of wet classification and gravity separa­tion processes, […]

GRINDING GRAINS INTO FLOUR For thousands of years, grinding grains to make flour was the primary application of grinding technology. Beginning in about 100 bc, the development of mills driven by water and wind revolutionized the practice of agriculture. Although the importance of bread is underrated today, it is still the main food in many […]

In 1830 a patent was issued in United States for a machine …which comprised a wooden box containing a cylindrical drum, apparently made of wood, on which iron knobs or hammers were fastened. The expectation was that this drum, when revolved at 350 rpm, would shatter the rock fed into the box. (McGrew 1950) This […]

By the middle of the 19th century, the need for better fine-grinding mills had become apparent. Stamps driven by steam engines had limitations on how fine they could grind, particularly on the size of the screens used to remove the desired product from the breaking chamber and keep the oversized material in the chamber. Querns […]

Figure 7.18 shows three types of classifying liners. As clinker grinding mills increased in length, it became necessary to devise a system by which the coarse balls were continu­ally thrown back to where the coarsest particles of ore were at the feed end of the com­partment. Hardinge had designed his “tricone” mill for this purpose, […]

Vibrating Mills One method of keeping balls in motion so that they will collide and break particles trapped between them is vibration, and a vibrating ball mill was developed and patented in Germany in the 1930s. Vibrating ball mills are either vertical or horizontal and can be used as continuous flow or batch mills, and […]