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Picking a Perfect Primary


IMPACT CRUSHER AT AN APAC-KANSAS CITY QUARRY HAS THE OPERATION PRIMED FOR SUCCESS.

By Mark S. Kuhar

Impact Crusher at an APAC-Kansas City Quarry has the Operation Primed for Success.Dozens of contractors, businesses, municipalities, and state and federal agencies count on the crushed limestone aggregate produced at APAC-Kansas City quarries. One facility produces more than 400,000 tpy of crushed limestone for concrete and asphalt aggregate used for projects throughout the Kansas City area.

To process that much limestone, APAC Foreman Tommie Faulkenberry said he needs to be able to depend on every piece of equipment on APAC’s 400-acre site. That dependability all starts with the primary crusher. “If I can’t rely on that crusher doing the job without problems, it’s going to slow everything else down. So it’s great we have the MaxCap 600,” said Faulkenberry.

Challenge
In 2005, there was a need for a primary impact crusher at a new quarry being built on a greenfield site next to an existing operation.

The quarry required a primary crusher that could handle large boulders with a rated capacity of 600 tph. The plan was to crush up to 500 tph of quarry shot limestone and reduce it to a nominal 4-in. minus.

APAC also needed to consider how the primary would work together with the secondary crusher, which was to be a cone crusher due to the requirement of a controlled feed.

Solution
After considering a number of different crushers from various manufacturers, the customer began to realize the benefits of the Universal MaxCap 600 Impact Crusher.

“They took a lot of factors into account before purchasing the MaxCap 600,” said Gerry Mangrich, McLanahan regional sales manager. “The feed size, output gradation and adjustment control played a big part in their decision.”

McLanahan’s Universal MaxCap 600 is known for its large-expansion chamber above the rotor. The back wall is lined with massive impact plates that deflect the expanding material in a controlled loop within the crusher, providing maximum reduction by allowing pure impact energy to flourish unimpeded.

The secondary cone crusher’s need for a controlled feed is where the MaxCap 600 really excels, Mangrich noted. Since cone crushers require a controlled feed, the output of the MaxCap can be easily adjusted to provide that control. Likewise, the C-shaped hammers are cast with a protruding leading edge that provides for a more consistent top size through the life of the hammers.

“It’s very easy to adjust the MaxCap because of its hydraulics to account for hammer wear, which is important for working with the secondary cone crusher,” said Faulkenberry.

Perhaps the most important feature of the MaxCap 600 is the hydraulic control that allows for adjust-on-the-fly modifications of both the feed plate and breaker plate. A simple 15-hp electric/hydraulic power pack with analog controls provides a means to eliminate any bridging in the crusher and to manipulate the crusher’s output gradation with fingertip control.

The crusher can accept boulders up to 40 in.
The crusher can accept boulders up to 40 in.

Results
Faulkenberry said he has been pleased with the performance and reliability of the MaxCap 600.

“The primary crusher has been doing a real good job ever since we’ve had it in, with a very limited amount of downtime,” Faulkenberry said. “I haven’t seen any big problems with it in the last eight years, and we’re generally operating at about 400 to 500 tph, though it could handle much more.”

The MaxCap 600 was chosen based on its rated capacity of 600 tph, but field experience has proven it is capable of higher capacities, and it is now rated 600-800 tph. The crusher can accept boulders up to 40 in. (101.6 cm), while other impactors are limited to maximum feed sizes of 30-36 in. (76.2-91.4 cm).
The MaxCap also generates an output gradation where upwards to 75 percent is minus 1.5 in. (3.81 cm). This is nearly 30 percent more product at the primary stage compared to other impact crushers, without creating excessive fines, and often reducing the minus 4 mesh.

Faulkenberry said he appreciates the added capacity. “It will crush all the rock we can put to it. I’d love to be able to get even more through it,” he continued. “There’s no problem at all with handling the input, and there’s a good consistent flow in getting the stone through the system.”

Faulkenberry said he would recommend the MaxCap 600 to others because of its limited maintenance and overall efficiency and that what he likes most about the crusher is its simplicity. “It’s easy to use, easy to operate and easy to maintain. It’s one thing out here on the site that I don’t have to spend time worrying about,” continued Faulkenberry.

In 2012, McLanahan Corp. acquired Universal Engineering Corp., integrating the manufacturing and service for Universal’s equipment as part of its own. McLanahan has worked hard to ensure a streamlined transition in terms of the quality, service and support for the MaxCap 600 and other Universal equipment.

The company’s representatives agree. “The legacy of Universal is now carried on by McLanahan, and it’s been a good thing for the customers,” said John Donohue, territory manager for Continental Equipment Co., which represents the McLanahan line.

Faulkenberry said McLanahan has excelled at meeting the expectations of quality and service that APAC had previously expected from Universal. “The MaxCap has operated very well since it’s been installed. But any time I have issues, one call to McLanahan, and I get them taken care of quickly,” said Faulkenberry. “Like I said, it’s all simplicity – easy to operate, easy to maintain.” E

Information for this story courtesy of McLanahan.


Universal MaxCap Impact Crusher PrimaryMore on the MaxCap

The Universal MaxCap Impact Crusher Primary features the best of both the Andreas- and New Holland-Style Primary Crushers. It offers a large expansion crushing chamber like the New Holland style and has the technology of the Andreas style crusher to break the rock.

The primary stage impact chamber utilizes fixed impact plates promoting vertical expansion upon impact and controlled re-entry into the impact zone for maximum reduction. The secondary stage impact chamber has an “on the fly” adjustable curtain with cast wear plates. This feature controls product top-size as the chamber is adjusted to compensate for changes in product requirements.

The Universal MaxCap provides for maximum capacity as a true primary impact crusher and delivers a high-quality, cubical product at a lower cost-per-ton.

Standard Design Features:

  • Main Housing – heavy-duty fabricated plate steel construction comprised of an upper and lower section with inspection doors and hatches on sides and back.
  • Upper section pivots hydraulically to provide easy access to the interior for general maintenance and periodic hammer changes.
  • On the fly hydraulic adjustment mechanism with hydraulic relief and auto-reset simplifies adjustment settings on the adjustable curtain and eliminates downtime due to uncrushables.
  • Feed plate pivots hydraulically with shim adjustment, during operation, to vary the angle of feed into the impact zone and accommodate changes in material characteristics.
  • The impact chambers and feed plate are comprised of interchangeable cast manganese plates for maximum wear life and impact resistance.
  • Interior walls of the impact chambers are protected with replaceable abrasion resistant steel liners, to provide extended wear life.
  • Rotor Assembly – solid steel rotor of heavy steel plate construction with keyless mounting of the rotor body to the shaft, spherical roller bearings, and quick-change wedge system for retaining the one-piece hammers.
  • Three rows of vertically installed heavy duty curved manganese hammers are reversible with protruding leading edge for optimum capacity and greater utilization.
  • Hydraulic Unit – consisting of a 15-hp electric/hydraulic power unit to control the hydraulic cylinders for the hood, secondary stage curtain wear plate and feed plate.