Хонинговальные головки

Ball mills became the dominant fine-grinding machine in the 20th century. By 1900, the ball mill patent litigation in France had ended, and inventions to improve fine-grinding processes were in full flood. Inventing a machine is one thing, selling it another. One event that went far to establish the credibility of wet ball mills as […]

In those days all paints were ground in very small quantities by hand, and it was not unusual for an apprentice to work on a couple of ounces of paint for many months. In the age when few colours were known it was the colloidal grinding of paints that enabled the great artists of the […]

First Generation Dynamic air separators have several common characteristics: ■ Internal rotors that are also feed distribution plates ■ Airflows generated by internal or external fans ■ Collision blades that interrupt the flow and rejection of coarse particles FIGURE 9.11 Alpine Zig Zag classifier FIGURE 9.12 Askham air separator (Butler showing the passages and collision […]

Aggregates — hard, inert materials used for mixing in various-sized fragments with a cementing material to form concrete or mortar. Air separators — a machine where air is the carrying medium instead of water, and par­ticles are separated by centrifugal force. Static separators are similar in operation to hydrocyclones, but dynamic separators have internal rotating […]

As the world’s population steadily increased (see Table 1.1), so did the demand for con­verting raw materials into valuable commodities such as medicines, minerals, and pig­ments. By the start of the 20th century, these and other commodities were being produced in volumes of tons (see Table 1.2). Along with the spectacular increases in population and […]

His berries, nuts, acorns and corn were pounded into meal; and his invention of the first pounding appliance constituted, without doubt, one of the earliest attempts to devise an instrument useful in the peaceful arts. (Bennett and Elton 1898-1904) In this chapter we discuss how stones driven by muscle power—which were first used for grains […]

In 1895, Thomas Edison was responsible for a remarkable innovation in crushing. Edison believed that high-grade deposits of iron ores in the eastern United States were running out, and he decided to develop a deposit of low-grade ore containing magnetite at a treatment rate of up to 6,000 tpd. Minimizing mining and crushing costs was […]

Many roller mills were sold from 1930 to 1950, but there was little enthusiasm for new designs because of the economic depression and World War II. The revival of industry after the war increased the demand for materials, and new mills were required with grinding chambers that had higher processing capacities. Fixed Rollers and a […]

For most of the 20th century, equipment manufacturers brought the main improvements to the technology of fine grinding. The Allis-Chalmers Company, for example, with its research programs and extensive publications, was a leading manufacturer of crushing and grinding machinery and one of the main contributors to better grinding technology. The Allis-Chalmers Company, then, is a […]

The first mills to produce fine particles at a rate of a few tons per hour were slow-speed ball mills and roller mills that were developed about 1880. By 1920, there was a strong demand for fine grinding as industry revived after World War I. By then the ball mill was so successful that for […]