Shumar - Coal Crushers

All Shumar Crushers have two machined rolls to which the crusher segments are bolted. Each Roll is generally fitted with six crusher segments; some large roll diameter primary crushers do have more segments per roll. Manganese Steel segments are used in all Primary and most secondary crushing applications. All segments are hand ground to master a drum for proper seating. One roll is fixed while the loose roll is spring loaded to minimize shock loads and damage to the crusher during a stall, resulting from non-crushable material, mostly tramp steel, being fed to the crusher. 

The loose roll position can be adjusted using the adjusting spindles when product size needs to be altered or fine-tuned or when adjustment is required to compensate for wear. The loose roll bearings slide on the crusher main frame and are guided at the bottom by a wearing strip fixed to the main frame and at the top by a separate top guide arm. Phosphor bronze and steel wearing strips are provided for all sliding surfaces. The bearings are spherical roller bearings and are sealed by a taconite type labyrinth seal. 

To protect the seals, the loose bearing housings are designed to pivot in the event of the roll kicking out. The lower hood is a permanent part of the frame. The outlet chute is fitted to this section of the hood. The crusher has hood seals on the hood sides, which makes the crushing chamber sealed to prevent dust escaping. The crusher is supplied with a V-belt drive, a guard and a drive stand. A pair of geared motors drives each roll independently. Both drives are situated on the same side to make the crusher more compact. 

An optional extended frame can be supplied so that the crusher can be removed with its complete drive. Usually purchased with the extended frame option, is a set of rollout wheels used to roll the crusher out to a maintenance area. The rollout wheels are hydraulically extended to lift the crusher off the rails. The segments fitted to each crusher are carefully chosen to suit the customer’s needs. 

However, should the need arise; special segments can be designed to suit that particular application. Whilst Shumar has a reference list of over 400 units worldwide, every crusher is custom designed to the customer requirements, thereby not restricting the design stage of any installation to existing equipment dimensions. Primary Crushers Input Sizes range from 300mm to 3000mm, with Secondary and/or Intermediate Crushers having input sizes ranging from 3mm to 300mm. Primary Crushers Capacity range from 180tph to 11000tph, with the Secondary and/or Intermediate Crushers having capacities from 1tph to 4000tph, all very dependent on the duty and reduction ratio.

Reduced Fines Production

As sized products generally attract a higher sales price than fines, reduced fines production means additional higher profitability or makes the product more competitive in the market. This is a major factor in Australia as most product sizes are sold as -50mm. Less wind loss and environmental dust problems.
Large savings in washings costs as larger size coal is cheaper to wash then fines. Saving in capital cost of washing plant as fines plants are generally more expensive to build. Less water is used in coarse plants and therefore less water pollution problems will occur. Less fines means lower external moisture content in the product. In many existing plants, capacity of the plant has been throttled back by the fines treatment, washing plants having reached saturation while the rest of the plant is underutilized.

Reduction in Power Consumption

Regardless of the product sizes produced, power is required to break coal. Unnecessary fines production causes excessive power consumption. Direct cost saving of motor installations, switch gear, cable and power consumption.

Reduction of Crusher Segment Wear

Crusher segments last longer when the crushing is done efficiently, i.e. with the correct crushing ratio, roll speed and roll diameters are used.
Direct saving in less frequent replacement costs and down time saving.

Maximising Desirable Product Size Distribution

This means producing the maximum quantity of the desired product that the market requires, i.e. getting the maximum useful tonnage of all coal mined at an optimal price.

Tramp Protection & Segment Wear

The crusher has one fixed roll and a spring loaded loose roll. The spring tension is variable to satisfy the requirements of the customer as far as the desired amount of kickback required. One of the main functions of the spring loaded loose roll is to use the springs to absorb the initial shock loads when non-crushable material is fed into the crusher. This together with a V-belt drive system, helps protect the geared motors, bearings and shafts from shock load damage. The position of the loose roll can be adjusted for various product requirements and segment wear, the movement of the roll is spring assisted.