Crushing & Screening

Roller Mills

In the Griffin Mill, there is a single roller suspended in a similar way to the rollers in a Huntington mill. The roller is about 18 inches in diameter, and rolls on the inside of a die ring 30 inches in diameter. It takes material up to 1½ inches in diameter, and crushes either wet … Read more

Using Mercury in Gold Ore Crushing

The earliest machines used for the purpose seem to have been stone mortars, in which the gold quartz was crushed by stone-hammers, or by large rocks raised by levers and let fall, whilst the fine material was subsequently washed out with water. The heavy particles of gold then settled to the bottom of the mortar, … Read more

Stamp Milling

The stamp mill‘s battery evolved, no doubt, from the pestle and mortar was not introduced until a comparatively recent date. Beckmann states that mortars, mills, and sieves were used exclusively in Germany throughout the whole of the 15th century, and in France stamps were unknown as late as the year 1579. Brough has suggested that … Read more

Rock Breakers

There are two classes of rock breakers machines in general use: Jaw crushers with reciprocating motion, and gyratory crushers The Blake and the Dodge crushers are representative of the former class, and the Gates and Comet crushers of the latter. The Blake Crusher is shown in section in Fig. 22. The rock is crushed between the stationary jaw, … Read more

Crushers

It is difficult to define exactly the meaning of the terms crushing and grinding, or crushing and pulverization; the finer crushing stages may embody a certain amount of pulverizing or grinding, but in the main, crushing may be said to cover the reduction of stones or ores to a size of ½ inch, and in some … Read more

Rock Abrasion & Crushers

This section of the Paper deals with the abrasive character of rocks affecting crushing machinery. The investigation has followed two courses, firstly, an analysis of the existing data relating to the testing of road-making stones from its bearing on the abrasive wear of crusher-parts, and secondly, an experimental investigation into the correlation of abrasive wear … Read more

Jaw Crusher

This crusher is the finest of our lines of jaw crushers which we offer. Others include: Superior, Type “B” Blake, Fine-Reduction and Dodge — sizes, 4 by 6 to 84 by 66 inches. A reciprocating machine, the crushes material in a straight line between jaws — without grinding or rubbing surfaces. LOWER JAW CRUSHING COSTS As … Read more

French Crushability & French Abrasion Index

The french crushability and french abrasion test gives an abrasivity index and a crushability index that will rate the material in comparison with other materials. The french abrasion test is mainly used to estimate hammer wear life in impactor applications. The crushability index is a measure of how easily the material breaks down. The test … Read more

How to Size of Crushing Plant

When calculating the size of a crushing plant, it is not advisable to design a crushing plant to run for 24 hours per day. The machines are subjected to greater shocks and rougher wear than grinding and concentrating machinery and need more frequent attention in consequence. It is an almost universal custom to crush the … Read more

Small Screw Conveyor

Small Screw conveyors are used principally for bulk conveying of light and fluffy dry material, materials which dust badly when conveyed, hot materials which cannot be handled on rubber belts, and for conveying of liquid pulps. They may be installed on an angle for lowering or elevating materials. With the bottom or end of trough … Read more