Sampling Sizers/Roll Crushers

Sampling Sizers/Roll Crushers retain the key features and benefits of the larger machine designs but are packaged into compact, cost-effective solutions specifically tailored to reliably and efficiently handle lower capacity applications.

Double Roll Crushers are a widely used crusher type and offer advantages in relatively high capacity for a given machine size, low overhead requirements, relatively low power requirements, integral tramp relief, the ability to handle sticky materials and the ability to produce a cubical product with minimal fines generation.

Sizers offer many of the same performance features as Double Roll Crushers, with the added features of directly driven rolls, very low overhead requirements and a relatively small footprint for the machine size.

Sample Double Roll Crushers and Mini-Sizers can be used in a wide variety of applications and industries. These machines are widely incorporated into mining and power generation applications that handle soft to moderately hard, friable materials such as coal, coke, limestone, salt, potash, clay, oil sands, trona, shale, bauxite, and other materials with similar characteristics.

How Sampling Sizers/Roll Crushers Work

Sample Double Roll Crushers and Fine Grinding Sizers operate in a similar, simple fashion. Material to be crushed is fed into the top of the machine, where it is crushed through two rotating roll assemblies and passed out through the bottom of the crusher. The crushed product size and gradation is based on the distance between the rolls and the tooth profile on the crusher rolls. Fewer, larger teeth and wider roll settings result in a coarser crushed product, whereas more, smaller teeth (or simple beaded rolls) and smaller roll settings result in a finer crushed product. Regardless of the tooth configuration or roll setting, the crushing principles are the same. Material is crushed as a result of the combination of impact, shear and compression. Despite the fact the rolls are rotating at a relatively slow speed, some material breakage occurs when feed material enters the crusher and is impacted by the crusher roll teeth. Shearing occurs when feed material is captured between the roll teeth and/or between the roll teeth and sizing combs. Compression occurs when material is forced between the rolls or between the rolls and sizing combs.

Sizer rolls are directly driven by right-angle gearmotor units. This arrangement allows for differential rolls speeds that aid in processing wet and sticky material, but it also simplifies the design of the machine and allows for the minimal footprint associated with sizers.

Sample Double Roll Crusher rolls are driven in one of two ways. The first is a dual drive arrangement where each crusher roll is driven by its own V-belt drive and motor. This permits differential rolls speeds that aid in processing wet and sticky material. The second arrangement is a single drive in which the first crusher roll is driven directly from a V-belt drive and motor arrangement, but the second roll is driven by an inter-roll V-belt and tensioner arrangement.

Sample Double Roll Crushers also offer a spring-loaded toggle arrangement for tramp relief. In this arrangement, the on-crusher roll is movable. When uncrushable objects enter the crusher and are drawn down in between the rolls, the movable roll rebounds away from the stationary roll engaging the toggle. When uncrushable material clears the crusher, the roll springs back into its original position without interruption to the crushing operation.

Regardless of which type of machine is used, feed material is fractured along naturally occurring fault lines in the material particles, reducing the feed material to the desired crushed output size while minimizing fines generation.

Why McLanahan Sampling Sizers/Roll Crushers

McLanahan has extensive experience in crushing applications, particularly crushing applications involving Roll Crushers and Sizers. In addition to being backed by this experience, Sample Double Roll Crushers and Sizers offer a simplified design and long-term, reliable operation with minimal maintenance requirements. Low profile designs (and minimal footprint in the case of sizers) make for easy implementation into plant layouts. Rugged construction, oversized roll shafts, replaceable liners and hard-wearing rolls ensure that these machines will handle difficult applications while continuing to reliably produce crushed material. Adjustable roll settings, along with a number of other design options, help tailor crushed product size and deal with difficult-to-handle, wet and sticky materials. On-site testing is also available to ensure that the crusher configuration selected is the best option for your application.