Horizontal Axis Crushers Manage Tough Chips
There are a few shop processes that are necessary evils: One of them is chip management and removal. To make this process less daunting and as efficient as possible, it pays to explore options and find what type of chip removal is best for an application.
In the case of Ingersoll Tillage Group (Hamilton, Ontario, Canada), an abundance of alloy chips was the problem it faced on an hourly basis. The goal was to come up with a way to deal with 100 to 150 pounds of chips produced from three machining stations per hour.
“Our material has a tendency to create hairballs of turnings, which are air-quenched,” says Tom Dyment, project manager. “Because of the system configuration, it’s extremely tough to remove and handle the turnings at the cell.” The facility, whose Boulder, Colo., parent company was founded in 1979, uses automated processes including robotics and heat treatment to produce 1.5 million agriculture and landscaping disc blades annually for the OEM agricultural manufacturing industry. The facility also manufactures coulters, openers, sweeps and other opener assemblies. Ingersoll Tillage markets its products through distributors in ten U.S. states and in Japan.
Many of the discs the company produces are used by farmers to cut through last season’s crop residue, which requires them to be tremendously strong and sharp. “We use a patented boron alloy steel composition that is
extremely tough and resistant to fatigue or fracture failure,” Mr. Dyment says. “Our discs are known for maintaining their strength and sharpness because of their metal composition and how we manufacture them.”
New Machine, New Problem
In 2009, the company commissioned a new, custom-built, three-station, PLC-controlled lathe cell with integrated, visually guided robotics. The lathe profiles cutting edges on one or both sides of a flat disc blank ranging between 2 and 10 mm in thickness. Because of guarding requirements for the cell, direct access to the machining area to remove turnings became a problem.
When Mr. Dyment knew he had to find a way to handle the 100 to 150 pounds of chips coming from each of the three stations per hour, he looked no further than PRAB Inc. “The PRAB name is well known and respected by our tradesmen,” he says. “We often rely on the opinion of the people who have to maintain and repair equipment as a resource to measure product performance.”
Turning to a Solution
PRAB’s solution consisted of three horizontal axis crushers to reduce the particularly tough boron steel alloy chips into flowable, shovel-grade chips that are conveyed out of the safety-gated machine zones using magnetic conveyors. From there, they are binned and removed to a central storage, about once per shift.
The crusher’s single horizontal rotor sweeps chips from a stationary screen in the bottom of the housing, up and across stationary cutting tools. After passing the tools, smaller chips tumble over the rotor, through the screen and out of the crusher. Chips too large to pass are combined with new material entering the crusher and are swept back across the tooling for further size reduction.
“Applying the chip reduction solution allowed us to directly reduce the turnings at the source,” Mr. Dyment says. “In addition, we saw an immediate increase in uptime of between 10 and 15 percent. We also eliminated a safety hazard, were able to secure a better price for recycled metal due to a higher density, and reduced bin changes by 60 percent per shift. This new process has helped us get more money for our waste metal and improve our efficiency and safety.”
Cutting More than Earth
Although the horizontal axis crushers have been successful at reducing the unique turnings to shovel-grade chips, it hasn’t come without a few lessons learned.
Mike Dayton, PRAB product engineer, says, “We’ve cut our teeth on a new metal composite and have had to make some modifications to the horizontal axis crusher to withstand the enormous fight the metal puts forth. In the end, the knowledge we’ve gained results in a better product for future customers.”
Mr. Dyment agrees. “We knew the boron steel alloy was going to be particularly abusive to any reducing equipment. PRAB has really worked hard to understand the issues and collaborate on modifications that would reinforce the efficiency and reliability of the process.”
Ingersoll Tillage’s new horizontal axis crushers have reduced the size of the company’s difficult alloy turnings for disposal or further processing, such as wringing, to reclaim valuable cutting fluids and coolants. The size reduction alone has enhanced worker safety, increased productivity and enhanced efficiency of storage and transportation.