Roller Crusher or Roll Crusher Overview
SBM roller crushers are available with Gundlach's breakthrough 3-D crushing technology that includes intermeshing continuous tooth roll design and positive roll timing that delivers the industry's best dimensional product control, fewer fines and elimination of over-size material. SBM's roll crushers deliver higher quality cubical product, minimal fines and consistently repeatable performance for sizing coal, coke, glass, fertilizer, potash, salts, lime, limestone, soft ores, friable materials and industrial minerals.
Roller Crusher or Roll Crusher Working Principle
Roller Crushers are compression type crushers, and were once widely used in mining. They have, within the last 10 or so years, fallen into dis-favor among mining and processing companies. The probable reason is because the large mines require very large crushed product output with minimal cost, makes the roll crusher uncompetitive. The roll crushers are not nearly as productive as cone crushers, with respect to volume, and they do have a little higher maintenance associated with them. Roll crushers do, however, give a very close product size distribution, and if the ore is not too abrasive, they do not have high maintenance costs.Roll crushers have a theoretical MAXIMUM reduction ratio of 4:1. If a 2 inch particle is fed to the roll crusher the absolute smallest size one could expect from the crusher is 1/2 inch. Roll crushers will only crush material down to a minimum particle size of about 10 Mesh (2 mm). A roll crusher crushes using compression, with two rolls rotating about a shaft, towards the gap between the rolls. The gap between the rolls is set to the size of product desired, with the realization that the largest feed particle can only be 4 times the gap dimension.The particles are drawn into the gap between the rolls by their rotating motion and a friction angle formed between the rolls and the particle, called the nip angle. The two rolls force the particle between their rotating surface into the ever smaller gap area, and it fractures from the compressive forces presented by the rotating rolls.
Some major advantages of roll crushers are they give a very fine product size distribution and they produce very little dust or fines. Rolls crushers are effectively used in minerals crushing where the ores are not too abrasive and they are also used in smaller scale production mining of more abrasive metal ores, such as gold. Coal is probably the largest user of roll crushers, currently, though. Coal plants will use roll crushers, either single roll or double roll, as primary crushers, reducing the ROM coal. Usually, these crushers will have teeth or raised forms on the face of the roll. (Roll crushers used for minerals and metal ores have smooth faced rolls.)
Roller Crusher or Roll Crusher Crushing Material
* Coal: from ROM coal to clean coal, lignite (brown coal), bituminous, sub-bituminous, and Anthracite including frozen agglomerates
* Coke: petroleum coke, metallurgical coke, green or calcined
* Glass: cullet or bottles, plate glass, overrun glass on production line
* Fertilizer and potash: MAP, DAP, potash ore and flake among others
* Salts: rock salt, solar salt, KCl, NaCl
* Lime and limestone: soft to medium limestone and dolomites for sorbent in boiler application, burnt lime, ag lime, hydrated lime
* Soft ores: shales, clays, phosphates, oil shale
* Friable materials: ash, boiler slag, nuts and nut shells, cement clinker, ceramic floor tiles
* Minerals: kernite, borax, caliche, bauxite, phosphate, talc
* Hard to handle materials such as graphite electrodes, hot material, and sticky materials
* Hot iron sinter
Roller Crusher or Roll Crusher Capacities
Feed size: up to 1200 mm in size
Product sized to: typical products are 100 mm, 50 mm, 38 mm, down to 6 mm depending on feed size
Throughput: from as low as 10 TPH up to over 6000 TPH, depending on material, feed size and product size
