Models of Primary Impact Crushers
One of the first Andreas Impact Crushers manufactured in the USA, the McLanahan line was originally designed by Universal Engineering Corp and were introduced as primary impactors to provide easier maintenance. Andreas Impact Crushers are capable of withstanding the rigors of accepting boulder-sized feed material.
A heavy-duty rotor generates a high-intertia impact forces capable of a 12:1 average reduction ratio and provides recesses between the extra-thick rotor discs for tramp iron production. C-shaped hammers provide a more consistent gradation throughout the life of the hammer and can be vertically lifted from the rotor for reversing or replacement, resulting in more product with less downtime. Reinforced steel curtains provide the controlled material flow through the crusher and allow for quick, simple adjustments to maintain product quality.
However, these low profile impactors, while easier to make portable, do not have the expansion chamber above the rotor. Boulders enter the chamber, and the rotor is forced to shear at the bottom of the boulder until it’s small enough to shatter. Most manufacturers recommend a top size feed to their Andreas-style impactors.
The New Holland-style crushers are also known as Primary Impact Breakers. These crushers are known to take huge feed sizes and generate cubical products at better than 20:1 reduction. Its free-flow design combines a large expansion crushing chamber; a large, solid, fabricated rotor; upper deflector screen gate with vertical opening; and lower adjustable screen gate for precise product control with maximum output.
In many cases, the primary breaker is able to produce 75% minus 1-1/2”. This means 75% of the feed is already product for most base plants, leaving only 25% for further reduction at the secondary crushing stage.
As with all primary impactors, a heavy chain and rubber curtain in the feed chute reduces material from rebounding out of the crushing chamber, while also keeping dust to a minimum. McLanahan incorporates another common feature of drilled and tapped wear liners for the interior to the crusher wherever possible. This secures the liner while providing maximum utilization of the wear metal.
The MaxCap Primary Impact Crusher was introduced as a hybrid impactor combining the large expansion chamber of the New Holland with the ease of maintenance common to the Andreas Impactors. Maximum capacity of a high-quality, cubical product at a lower cost per ton can be achieved with the MaxCap.
The MaxCap Impactor accepts boulders larger than any comparable Andreas-style crusher. The feed chute in the MaxCap provides optimum feed angle and hydraulically adjusts under load to ensure continuous flow into the rotor assembly. The manganese hammers work-harden and feature a protruding leading edge to provide for optimum impact force throughout the life of the hammers. The breaker plate is hydraulically adjusted for product control, and may be used under full load, providing adjust-on-the-fly capability.
The MaxCap Impactor is available in model sizes that range from 600 tph to 1800 tph. At these tonnage rates, the MaxCap is excellent for stationary installations. The smaller models may be pit-portable, but they require more preparation for the highway.
The VersaCap P-Series and R-Series Primary Impactors are low-profile and very well adapted to portable plants. These primary impactors feature interchangeable components that can be fit to each customer's specific application. Standard two-curtain designs can be field modified to a three-curtain design, and rotor assemblies are available in three- or four-bar designs. Each VersaCap housing and rotor assembly has a heavy-duty construction and provides unmatched durability while minimizing downtime and increasing profitability.
VersaCap Impactors are engineered wih a simple hydraulic-assisted shim adjustment to minimize downtime while keeping the crusher operating at optimum performance. They are also designed with more curtain retraction than competitive designs, allowing additional tramp iron protection. In addition to the shim adjustment for the curtains, an optional semi-automatic adjust system provides adjust-on-the-fly capability with fingertip control under load. If you prefer a programmable logic controller with touchscreen, our full automation package also includes hands-free calibration.
The VersaCap R-Series Impactor is designed for highly friable material like concrete rubble, and performs well in a single-crusher closed circuit. The material passing through the VersaCap Impactor is conveyed to a screen, where the oversized material is then directed back to the VersaCap. The R-Series VersaCap may also be used in aggregate and mineral operations as a secondary crusher. The optional third curtain may also be field installed when desired.