For years, it’s been a big question an operation must answer when choosing a purpose-built material handler for its recycling facility, mill yard, port or scrap yard: Do the speed and flexibility of a tire model work best for the company, or should it choose to go with the stability and sure-footed operation of a track machine?
Truth is, operations have room for both styles of machines, and today’s wheeled handlers have advanced to the point where companies don’t sacrifice much when they choose between wheels or tracks.
“Most wheeled material handlers offer four-wheel drive, so they can power through marginal underfoot conditions where track models previously offered a significant advantage,” says Steve Brezinski, Terex Fuchs material handler product manager for Southaven, Mississippi-based Terex Construction Americas.
Still, many operations have had previous experience with track-mounted modified excavators and cable cranes, and their initial consideration is to stick with what’s familiar when it comes to drive systems for purpose-built material handlers.
Chuck Rosenberg, president of Hastings, Nebraska-based City Iron and Metal Co., says, “Initially when considering the Terex Fuchs material handler, I thought the tracks provided stability and the ability to move about the unpaved yard.”
While tracked machines do provide stability and flotation to easily traverse uneven, sloped and unpaved yards, operations shouldn’t automatically rule out tire drive systems as an option.
“We have worked with several companies that have ordered wheel models and previously only had experience with track machines,” explains Dick Mizzell, territory manager for Company Wrench, Carroll, Ohio. “The operators are initially concerned about lift stability, but they soon discover that the tire machines offer just as much, if not more, stability on picks, especially those to the side of the machine,” he continues.
What is best for your operation? Most of the time it boils down to how you will be using the handler and what you are comfortable spending. A site survey is the best place to start to select the right material handler for your operation.
Consider all aspects
When investing in equipment, information reigns supreme in making the best decision for the operation. “There’s no substitute for conducting a comprehensive site survey when making an equipment purchase, especially when it comes to material handlers,” advises Jay Young, scrap and recycling sales manager for Roadbuilders Machinery and Supply Co. Inc., Kansas City, Kansas. “You need to analyze exactly what size of machine, what reach is necessary and what drive system is required to meet production goals,” he adds. “The distributor or equipment manufacturer can help with this.”
Will the handler purchased be required to move about the yard, or will it be more stationary? Historically, tracked material handlers will be found in low-mobility applications, such as feeding a shredder or loading and unloading barges at the port. “One reason for this,” explains Brezinski, “is that crawler track models typically top out at speeds reaching about 3 mph, so selecting a track drive system in a high-mobility application may not be the best choice.”
Conversely, a tire-driven material handler can zip around the site at speeds four times faster than that of a machine with tracks. Therefore, if the handler will be unloading peddler traffic, sorting, moving and stacking recycled material or carrying logs from the stockpile to the feed mill, then the tire handler may be the best fit.
If the available space the handler has to operate is limited, then this can be a toss-up for selecting either tracks or tires. A track machine counter-rotates within its footprint, making it extremely maneuverable for operating in confined spaces. However, most sites are not so congested that the required turning radius of a tired machine will prove to be a hindrance to productivity.
“Most often the turn radius of material handlers will be less than 30 feet, which will provide more than ample mobility for doing the required work,” Brezinski adds.
Purpose built
When considering the productivity levels and the amount of material the handler will move to meet operating requirements, companies must look at the significant design differences with regard to lifting capacities between purpose-built material handlers and modified excavators. Regardless of whether the handler is equipped with tires or tracks, lifting performance will be significantly better than a similar-sized excavator, resulting in much higher productivity levels with the material handler.
“Both excavators and the material handler are purpose built,” says Joe Rich, CEO of Sunshine Recycling, Orangeburg, South Carolina. “Excavators are built to dig, and the [material] handler is built for recycling operations,” he says.
The hydraulics inside an excavator are not designed to handle much weight when the boom is extended, as City Iron experienced with its modified excavators prior to switching to purpose-built material handlers. “You can only reach so far with an excavator,” Rosenberg says, “and there was too much stress and strain put on the fittings when lifting heavy scrap material at the end of their reach.”
Therefore, a purpose-built handler will be able to pull material from a wider radius and may not need to move as far compared with an excavator. This makes site analysis important in determining how mobile the material handler will need to be, which is a determining factor in selecting a track or wheel drive system.
“Material handlers come in a number of sizes, offering varied reach capabilities,” Brezinski says. “For instance, Terex Fuchs boom/stick configurations offer a 31-foot reach at the low end with the MHL320 material handler to a 75-foot reach with the MHL385 model.”
And these purpose-built machines are powerful, he describes. “Our most popular size model, the MHL 350 tire machine (or RHL 350 track model), offers lift capacities in excess of 10,000 pounds at a 40-foot reach,” Brezinski adds.
Whether the undercarriages are track or tire, purpose-built material handlers of similar design offer nearly identical lift charts, providing no significant advantage of one design over the other in this respect.
What's underneath
A key factor in determining whether to choose track or tire drive is the terrain where the handler is operating. Historically, track drive systems have excelled in soft, uneven, sloped and marginal ground conditions. Track handlers spread their weight over a wider area than tire machines and, therefore, offer superior flotation in muddy conditions.
“Operations with unpaved facilities located in regions where sandy soils are prevalent will typically select track machines,” Brezinski says.
Additionally, if the machines will operate on or maneuver over steep grades, the advantage goes to track drive systems. More track area in contact with the ground it moves on offers better machine weight distribution, which helps with tractive effort and gradeability.
However, Roadbuilders’ Young argues not to entirely rule out tire machines for unpaved yards. “Even if the yard is unpaved, my recommendation is often to consider a tire drive system, if the machine is specifically designed for material handling,” says Young. “Tire machines can get around the yard faster, and the outriggers are quickly deployed to offer lifting stability, even with marginal ground conditions.”
With a paved facility or one that may be paved in the near future, the appropriate choice is automatic. Tire machines are the best fit. The steel tracks will damage paved yards, and, conversely, the pavement will increase the wear on tracks, reducing track life and elevating operating costs.
In addition, be prepared to pay a premium for tracked material handlers. A track drive system is more complex and includes additional components, therefore the initial purchase price will be approximately 10 percent higher on average than that of a comparable tire machine.
Maintenance considerations
Ongoing operating and ownership costs also will be higher with a track machine; consideration to the cost difference must be given and compared with the advantages offered by a track machine, sources say.
“It is more expensive to maintain a track machine and replace rollers, bearings and final drives,” Rosenberg points out. “Plus the tracks can get packed with mud, which is abrasive and causes wear.” This also can reduce the service life of a track drive system.
In general, daily drive system maintenance routines are more critical with tracks, especially when working in wet or muddy conditions. “Mud can push small rocks into the track components, and these need to be removed by power washing and/or [with] a shovel,” Brezinski says. Otherwise, mud and rocks can increase wear on track components.
The dual solid rubber drive tires on purpose-built handlers are designed for the extreme demands encountered at the port, scrap yard, mill yard and recycling facility.
“The solid rubber tires hold up well, and the dividers keep mud and debris from getting in between the wheels,” City Iron and Metal’s Rosenberg says.
He continues, “It’s all about speed in our business, and the Terex Fuchs handlers help us to do our jobs better, make us more competitive and allow us to keep up with the volume.”
Some factors to consider when choosing the proper drive system include whether the yard is paved or unpaved, whether the unit will be highly mobile or stationary and the size of the operating area. When in doubt, the equipment manufacturer or local distributor can help you wade through the process to ensure you select the right machine for your operation.
This feature was submitted on behalf of Terex Construction Americas, Southaven, Mississippi.
Explore the June 2015 Issue
Check out more from this issue and find your next story to read.
Latest from Recycling Today
- ReElement, Posco partner to develop rare earth, magnet supply chain
- Comau to take part in EU’s Reinforce project
- Sustainable packaging: How do we get there?
- ReMA accepts Lifetime Achievement nominations
- ExxonMobil will add to chemical recycling capacity
- ESAB unveils new cutting torch models
- Celsa UK assets sold to Czech investment fund
- EPA releases ‘National Strategy to Prevent Plastic Pollution’