Gyratory Crusher Design

The gyratory principle was the basis of several rudimentary designs, patented between 1860 and 1878, none of which embodied practical mechanical details-at least, not in the light of our present-day knowledge of the art. The, in 1881, Philetus W. Gates was granted a patent on a machine which include in its design all of the essential features of the modern gyratory crusher. The first sale of record antedates the patent by several months, a N° 2 crusher, sold to the Buffalo Cement Co. in 1880. That was crushers which carried the name of Gates to the far corners of the earth.

An interesting sidelight of these early days occurred in 1883 at Meriden, Conn., where a contest was staged between a Blake jaw crusher and a Gates gyratory crusher. Each machine was required to crush 9 cu. Yd. of stone, the feed-size and discharge settings being similar. The Gates crusher finished crusher finished its quota in 20 ½ minutes, which must have been a sad disappointment to the proponent of the Blake machine, who happened to be the challenger.

For some years after these pioneer machines were developed, requirements, viewed in the light of present practice, were very simple. All mining practice, were simple. All mining and quarrying, whether underground or open-pit, was done by hand; tonnages generally were small, and product specifications simple and liberal.

In the milling of precious metal ores, stamp as the final reduction machine. These were generally fed with an ore size that could be produced handily by one break through the small gyratory and jaw crushers which served as primary breakers. Even in large underground mining operations there was no demand for large crushers; increased tonnage requirements were met by duplicating the small units. For example, at the huge Homestake operation in 1915 there were o less than 22 small Gates gyratory crushers sizes Nos. 5 and 6 to prepare the ore for the batteries of some 2500 stamps.

Most commercial crushed-stone plants were small, and demand for small, and demand for small product sizes practically non existent. Many plants limited output to two or three products. Generally the top size was about 2 1/2- or 3-in. ring-size; an intermediate size of about 1 1/2 in., or thereabouts, might be made, and the dust, or screenings, removed through openings of about ¼ in. In ballast plants the job was even more simple, one split and an oversize recrush being all that was needed.