Crushers gyratory

The work index may be round experimentally from laboratoiy crushing and grinding tests or from commercial miU operations. Some rules of thumb for extrapolating the work index to conditions different from those measured are that for dry grinding the index must be increased by a factor of 1.34 over that measured in wet grinding for open-circuit operations another factor of 1.34 is required over that measured in closed circuit if the product size Xp is extrapolated below 70 [Lm, an additional correction factor is (10.3 + Xp)/l.l45X . Also for a jaw or gyratory crusher the work index may be estimated from... 

The development of improved supports and drive mechanisms has allowed gyratory crushers to take over most large hard-ore and mineral-crushing applications. The largest expense of these units is in relining them. Operation is intermittent so power demand is high, but the total power cost is not great. 

TABLE 20-11 Performance Data for Primary Gyratory Crushers ... 

Jaw crushers take lumps of several feet in diameter down to 4 in. Stroke rates are 100-300/min. The average feed is subjected to 8-10 strokes before it becomes small enough to escape. Gyratory crushers are suited to slabby feeds and make a more rounded product. 

Gyratory crushers 2. Rolling-compression mills with internal cutters ... 

Hard and tough Mica Scrap and powdered metals Jaw crushers Gyratory crushers Cone crushers Autogeneous mills Ball, pebble, rod and cone mills Tube mills Vibration mills Ball, pebble and cone mills Tube mills Vibration and vibro-energy mills Fluid-energy mills Moh s hardness 5-10, but includes other tough materials of lower hardness... 

Gyratory crusher Edge runner mill NEI pendulum mill... 

The gyratory crusher shown in Figure 2.6 employs a crushing head, in the form of a truncated cone, mounted on a shaft, the upper end of which is held in a flexible bearing, whilst the lower end is driven eccentrically so as to describe a circle. The crushing action takes place round the whole of the cone and, since the maximum movement is at the... 

The jaw crushers and the gyratory crusher all employ a predominantly compressive force. 

Crushers and grinders Cone crusher Gyratory crusher Jaw crusher Hammer mill... 

Beneficiation. Iron ore coming from the mine must be properly sized. A gyratory crusher is normally used for primary crushing down to approximately 300 mm (see Size reduction). Secondary crushing down to 25 mm can be done in a cone crusher. Fine grinding can be done by rod mills followed by either ball or pebble mills. In some cases, autogenous grinding can be used to replace the cone cmsher and rod mills. 

FIGURE 4J2 Crushing and grinding equipment, (a) Jaw crusher, (b) gyratory crusher, (c) vibratory mill, (d) fluid shear mill, (e) pin mill, (f) fluid jet mill, (g) hammer mill, and (h) ball mill. Redrawn from various figures in Perry and Chilton [1], Lowrison [2], and VanCleef[3]. 

The coals used in this work were first crushed to -1/4 inch using a gyratory crusher. They were then pulverized and sieved. All coals were dried under N2 at 80 C for 24 hours prior to pulverizing. The pulverizer produced fractions of -7+20 and -60+115 mesh. Most samples employed in this work were of -7+20 mesh. Only a few tests were made with coal of finer grind. 

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