Scrap Handling Equipment Focus: Working Gear

T ime and motion studies have long been used tomeasure productivity, with material handling taskswell suited to this yardstick. A scrap handler matched with the ideal attachment or work tool will move material from one place to another more safely and efficiently than any other combination.

Depending on the task, scrap yard managers and operators may choose from magnets, grapples, shears and other crushing attachments to get the job done.

Most observers agree these are the four major categories of attachments designed for scrap handlers, with several variations within each of those categories. And new variations are on the way as manufacturers look to eliminate steps scrap handler operators have to take when moving scrap.

GRAPPLES. In any scrap yard, one is bound to find several grapples dangling from the booms of scrap handlers. That’s because grapples are the most used and versatile of the attachments. The variations of the grapple include:

• Orange-peel - Grapples that have four or more tines. When the tines are open, the grapple resembles an orange being peeled back. These grapples are ideal for picking up a wide range of loose scrap. They can even be used to pick up auto hulks, but only one at a time. Orange-peel grapples are not best suited for small scrap, like turnings. Options include 360-degree rotation.

• Tulip - Grapples that have wide tines that form a seal when the grapple is closed. These types of grapples are also called full-leaf grapples. Because of its sealing capability, tulip grapples are perfect for handling small stuff. In addition, they can handle a wide range of larger scrap. Like orange-peel grapples, they can have the option of 360-degree rotation.

• Narrow-tine - Grapples that have skinny, fork-like tines. The narrow tines are ideal for picking up soft scrap because the tines can dig into the scrap more easily than orange-peel or tulip grapples. Its uses include handling paper, cardboard, plastics and tires.

MAGNETS. Large, circular electromagnet attachments are staples in many ferrous scrap metal operations. That’s because a lifting magnet can be used for several operations that a grapple cannot handle. One is cleaning up areas around the yard, as the magnet can virtually sweep areas. Another is removing ferrous material from railcars, as the magnet can get the scrap left over on the bottom, whereas a grapple cannot.

Lifting magnets come in many sizes, but the most common ones are in the 5- to 8- foot range. Ones that are smaller may not be able to do the job as effectively and have low cycle times, meaning the scrap handler operator has to make more swings of the boom.

Since lifting magnets are electromagnets (they can’t be real earth magnets because the scrap handler operator needs to be able to turn off the field to drop the load at some point in time), a power source is needed to generate the electromagnet field. Therefore, scrap handlers need to be equipped with an onboard generator. Along with the generator is a controller mechanism that allows the operator to manage the current.

Onboard generators are normally powered by the scrap handler’s hydraulic system and most have dedicated pumps. Here’s a quick test to see if a magnet you want to buy can be powered by the generator currently installed in your scrap handler. Use the equation: Power = (Force)(Current). If the force is 230 volts DC (what most magnets operate at), and the magnet’s rated at 80 cold amps (current), then a generator that can produce at least 18.4 kilowatts of power would be needed.

MOBILE SHEARS. Because not every location has a heavy-duty shredder or stationary shear, mobile shears are a popular and important addition to a scrap yard operation.

A powerful mobile shear, some with more than 1,800 tons of cutting force, can easily snap metal pipes in half or cut up large steel wheels from trucks, as well as I-beams.

While manual torch cutting may be needed in some areas, having a mobile shear to do the work of a torch can be far faster and safer. In addition, a mobile shear can be taken to a demolition site to tear apart steel structures or other items.

"If you are a small- to mid-size yard," says one manufacturer, "you need that mobile shear to handle the big stuff, because it’s not feasible to buy a heavy-duty shear or shredder."

Although these attachments work basically in the same fashion with jaw-like movement to crush concrete and rock, variations usually appear only in the shape of the teeth, size and types of steel used in construction of the attachment.

Crushers are used mainly in on-site demolition projects, but can also be used at a yard to free rebar and other metal imbedded in concrete used for construction or roads.