Grasan’s Crushing, Screening System Sets Up Easily

Wed April 18, 2007 - National Edition
CEG



Grasan road-portable system for crushing aggregates and concrete/asphalt rubble — primary impact crusher plant, side discharge conveyor, screening plant and closed-circuit return conveyor — can be set up quickly without a crane or special tools other than a front-end loader and block-and-tackle. Setup time will vary according to terrain, weather and ground conditions.

Normally the entire system can be set up or torn down in one day or less by an experienced crew.

The key to Grasan’s quick setup is its skid-on, skid-off hopper that can be transferred from its flatbed trailer to the crusher chassis in approximately 30 minutes, bolted down and ready for operation. A block-and-tackle and front-end loader pull the hopper onto the crusher chassis, where self-centering guides ensure proper alignment with the impact crusher.

With the hopper in place, the crushing plant is quickly raised and leveled on six independent hydraulic legs — two front, two middle, two rear — which provide total operational support without any braces, blocks or other support devices.

Each leg has its own raise/lower control with infinite, precise height adjustment and 324-sq.-in. (2,090 sq m) base pad for stable footing. The base pads raise to 12 in. (30 cm) above road level for travel.

The portable side discharge conveyor is backed into place under the crusher discharge feeder and raised to operating height. Crushed material is discharged directly out the side discharge conveyor in a short, straight line for a smooth flow to maximize production and minimize clogging.

The portable horizontal screening plant is then driven into place under the side discharge conveyor and its legs are blocked. Lastly, the portable return conveyor is positioned between the screen discharge and crusher feed hopper for materials that may need to be run through the system again for multi-step reduction to desired size.

In addition, portable radial stacking conveyors are usually added to the system to deposit crushed materials in piles according to product size and type of material.

Grasan impact crusher systems typically handle concrete and asphalt rubble, C&D debris, bricks, concrete blocks, stones and rocks. The impactor plant also is used to crush limestone and usually is designed with an end-discharge conveyor (instead of side discharge) when used primarily for that purpose.

The Grasan plant utilizes a Hazemag APPH hydraulically controlled primary impact crusher. This impactor normally requires no secondary crusher and is faster, more efficient and more versatile than jaw and cone crushers for recycling applications. Further, an impact crusher shatters concrete and normally leaves any embedded metals essentially concrete-free and ready for sale to metals recyclers.

A vibrating feeder under the crusher helps protect the discharge conveyor. A powerful, self-cleaning magnetic separator located near the top of the side discharge conveyor picks out ferrous materials such as rebar, dowel pins and wire mesh and deposits them into a truck or dumpster. The separator design utilizes a dings electromagnetic separator and Grasan electric-motor-driven belt with stainless steel cleats to protect it from damage. The head pulley and splitter chute also are stainless steel, which cannot be magnetized.

For more information, call 419/526-4440 or visit www.grasan.com.