The PWH single rotor hammer type breaker of the company also is used in stave as softly as the hard material, and has the very high reduction ratio, and may cause the stave product the granularity to be smaller than 3 millimeters.

Australian Voest-Alpine Corporation makes two patterns the double rolls breaker. One kind is loaded with the adjustment crushing roller gap mechanism and the elastic unloading roller. Two pattern breakers both may accord the different need, installing the first tone roller, the ripple roller and the serrated roller separately. The first type is used in stave materials and so on limestone, gypsum, pearlier; The second type is used in stave hard materials and so on iron ore, fever stone, slag and coke.

This company making the Sand breaker is suitable for the reduction ratio big situation. This company has also made the heavy intermediate crusher, using in the stave pebbles or the difficult garrulous rock.

Voest-Alpine Corporation has also made one kind of Centro breaker, and this machine is loaded with the high speed turbine type rotor, which is used in the grit gravel stave, and the product granularity is 50 . This machine concentrates by upside giving the material, and the material to the rigid stave cavity wall direction movement. The rotor has the wearing capacity smallest structure and the best stave effect. Productivity is about 50 tons/hour, this kind of breaker, is suitable in the stave 0～5  grade occupies 80% sand and crushed stone. This machine has two kinds of specifications: 1250  1250  and 1600  1600 , the actuation power is 5575 .

Stave and stave machinery

This article mainly elaborated the stave basic concept, introduced the commonly used stave machinery principle and technical, the stave machinery use scope and the choice, has made the detailed narration to the double roll type breaker, and introduced the breaker use.

1 Stave, the reduction ratio and the crushing circuit

1) Break 

Under the exogamic process, causes the material pellet to split the finely ground particles process, is called stave or the smashing. 

2) Reduction ratio 

Weighs the breaker the stave effect,commonly used reduction ratio this concept. After the breaker reduction ratio is raw material granularity and the stave product precision ratio of. It after expressed the stave raw material reduces degree.

The reduction ratio has the following several computational method.

① Of the material ratio of greatest granularity and the stave product greatest granularity calculates after stave in front of

In this in the formula  

 ——Stave front material greatest granularity;

 ——After stave material greatest granularity.

Because the various countries' custom is different, the greatest granularity value method is different. Britain and America take the material 80% can through the mesh width as the greatest granularity diameter, the former U.S.S.R 95% be able to pass the mesh take the material the mesh width as the greatest granularity diameter.

② Uses the breaker to the material mouth effective width and ratio of the dump mouth width

In this in the formula  

 ——The breaker gives the material mouth width;

 ——Breaker dumps mouth width;

0.8——Guaranteed the breaker bites the material the effective width is a material.

The dump mouth width value, the thick breaker takes the maximum dump mouth width; The breaker takes the minimum dump mouth width.

It is very convenient with this type computation reduction ratio, because is impossible in the production frequently to make the screening analysis to large quantities of materials, but uses this type, so long as knew the breaker to the material mouth and the dump mouth width, may calculate the reduction ratio. Is worth pointing out that,certain breakers, its dump granularity are not decided by the dump mouth size.