Scrap Handler Supplement -- Handling the Tough Assignments

As a visitor approaches a modern scrap processing facility, among the first things visible on the horizon will almost certainly be one or more cranes busy at the task of moving scrap material.

Standing tall enough to feed scrap into a super-sized shredder or into a waiting rail car, the scrap-handling crane at work makes for an impressive site. Whether moving scrap via a grapple or magnet, or reducing scrap items with a giant shear, a scrap handler in action creates a mixture of noise, motion and activity.

While the work performed by scrap handlers is impressive, scrap processors are aware that so, too, are the costs and responsibilities. When researching or shopping for scrap handlers, almost inevitably the first decision to be made is whether to go with a purpose-built machine or a converted excavator model.

BUILT WITH SCRAP IN MIND

While some might contend that the lines are beginning to blur, scrap handlers are usually placed into one of two categories: purpose-built or converted.

Converted models are usually modified excavators with the same boom and stick cylinder configuration that would be found on an excavating machine. Purpose-built scrap handlers are designed from an earlier stage specifically for the task of lifting and moving scrap metal.

LIFTING IN THE HEAVYWEIGHT CLASS

One area in which manufacturers of purpose-built scrap handlers say they have an advantage is in the lifting capacities of their machines versus an excavator converted for scrap handling.

Purpose-built scrap handler designers are able to configure the stick cylinder in a position that allows for greater lifting forces. Thus, purpose-built machine makers claim that the excavator design¡ªwhich is also designed to dig downward¡ªcannot offer the same lifting capacity as purpose-built models.

¡°Excavators are built for digging,¡± says a manufacturer. ¡°That's where all the forces are concentrated - up front so that the machine can dig down below grade. However, when that excavator is converted to a scrap handler, it now is lifting and swinging a load from side to side. That introduces new stresses and movements to the handler - stresses the excavator was never meant to experience.¡±

In addition to lifting capacity, makers of purpose-built models tout other advantages their machines offer. Examples they may cite: Scrap handlers need to have appropriately high cab seating for operators and a body made from thick steel plate designed to operate in areas where heavy and sharp objects are routinely on the move.

A CUSTOM SUIT OF ARMOR

In the scrap environment, durability is a cherished commodity. ¡°A scrap yard is very demanding on a scrap handler,¡± says one manufacturer. ¡°The machine is constantly cycling, swinging loads, maneuvering to load and unload, and generally taking a beating out there.¡±

Because of this environment, makers of purpose-built handlers tout the extra protection their models offer. One example cited by manufacturers is the covering of hydraulic lines, greatly reducing the chances of a severed line in scrap handling applications. Manufacturers have built in flanges on the gooseneck of the stick to protect the hydraulic lines that power the attached grapple or shear.

The flanges offer valuable protection when the machine is loading or unloading scrap from a railcar or truck and the operator inadvertently rubs the end of the stick against the side of the container or against some scrap. ¡°If one of those hydraulic hoses is damaged, the scrap handler is down,¡± says a manufacturer. ¡°The flanges are a simple design feature for protecting those lines.¡±

Other areas that manufacturers have targeted for protection are the operator's cab, hydraulic cylinders, the wheels, the undercarriage, and the turntable bearing.

Hydraulic cylinders can be protected by adding a protective shield over the cylinder ram so that when it retracts from the casing, the shield will guard it against any flying scrap. Hydraulic cylinders also can be inverted to minimize dust or dirt entering through the head seal.

For models with dual tires, one manufacturer has designed a shield to prevent scrap from being caught between the tires. Another manufacturer has enclosed its turntable bearing for added protection and uses an oil bath lubricating system instead of having to grease it by hand. Protective glass and shielding around the operator's cab is becoming standard as well.

While protection of normally exposed areas is desirable, processors should look for machines that don't have a lot of hoses or parts exposed in the first place. In addition, look for an uncluttered undercarriage with plenty of clearance under the crane so that scrap can't damage any operating parts there.

OTHER DESIGNED-IN DIFFERENCES

There is a fair-sized checklist of designed differences touted by scrap handler manufacturers as advantages to purpose-built machines. They can range from customized hydraulic and electronic systems to the positioning of the operator's cab.

Regarding the hydraulic system, many purpose-built scrap handlers have separate pumps: one for rotating the handler from side to side and for operating the attachment. Other companies that offer purpose-built machines use only one large pump, however, to power all movement aboard its scrap handler. ¡°Some handlers have separate pumps for the upper carriage rotation, and for the movement of the front and operation of the attachment,¡± says one manufacturer, ¡°but we use one main pump that is large enough to handle everything so that there is no noticeable decrease in power to any one area.¡±

Another company uses a system that matches pump flow to demand, which they claim maximizes hydraulic fluid circulation. This, in turn, gives better fuel economy and results in less heat build-up in the hydraulic system. ¡°This system also has a fine control so that when the operator moves the controls there is less jerking motion and a more smooth and even movement,¡± says the manufacturer.

As noted earlier, some manufacturers have added protective shielding around vital hydraulic lines. Others use added protection in the lines themselves. Either feature can prove important in preventing flying scrap from cutting or piercing a line and rendering the handler incapable of doing its job until the line is replaced.

As a long-term maintenance consideration, some manufacturers have protected the hydraulic oil cooler part to make sure dust and dirt don't contaminate it as quickly.

To protect wiring and other electronic components, many manufacturers use waterproof connectors and casings. Heavy-duty wiring can also increase operating efficiencies, according to some equipment makers.

One manufacturer has a free swing feature that allows the operator to disengage the swing brake, providing more control and safety when swinging a load.

Another area related to custom design is the positioning of the cab so that operators can adequately see what they are handling. Purpose-built scrap handlers generally claim a higher cab height, and one manufacturer even has a cab system that can be raised so that the operator can see inside trucks and railcars, and then lowered for more efficient travel.

CONVERTED TO PROVIDE AN AFFORDABLE OPTION

In addition to the array of purpose-built scrap handlers available, many manufacturers of hydraulic excavators offer models of their machines that have been modified to lift and move scrap. There are also several companies that will convert a pre-owned excavator into a scrap handling machine, providing a more affordable option for many small and mid-sized processors.

The 1998 Recycling Today Equipment & Services Buyers' Guide lists more than five dozen companies as providing hydraulic crane sales or services. While some of these are indeed manufacturers or national distributors of purpose-built scrap handlers, many others are established conversion shops. Some work directly with manufacturers to convert new-ly-made hydraulic excavators into scrap handlers that will be sold or leased as new equipment. Others, working independently,  acquire used excavators and perform conversions to fill orders placed ahead of time by customers, or perform the conversions and then sell their converted machines on the open market.

As part of the conversion process, manufacturers or conversion shops will take several steps to turn machines built for digging into scrap metal handlers. The resulting machines can provide an ideal option for small and medium-sized scrap processors who find purpose-built models to be beyond their means.

¡°They just want a reasonably priced crane,¡± says one conversion specialist of his customers. ¡°For a processor who has been using forklifts and small loaders, a conversion model with reduced lifting capacity or reach is still a large step forward.¡±

While noting that ¡°primarily the user for this product is the small to medium-sized yard,¡± the conversion specialist adds that ¡°once in a while, a large yard will call and to say they want a good stand-by machine or that they are buying for an application where a converted model will be suitable.¡±

BACKSIDE BALLAST

The addition of more counterweight is usually a key part of an excavator-to-scrap handler conversion. The added weight increases the lift capacity of the machine to prepare it for the heavy lifting encountered in scrap handling functions. While in theory it is possible to add too much additional counterweight, each original equipment manufacturer has guidelines for adding counterweight. In most cases, the process starts with frame reinforcement to ensure that the machine can bear the load of its added counterweight, a magnetic attachment, and a significant amount of scrap that will be lifted.

Counterweight can then be added in several forms, including additional fill to the standard counterweight, slabs of steel welded to the top of existing counterweight, and slabs of steel sandwiched between the existing counterweight and the frame of the machine.

A LOFTIER PERCH

Another common part of the conversion process includes the addition of cab risers to allow operators to better see into trucks, railroad gondola cars, barges and shredder in-feed conveyors. There are two common varieties of cab risers. One is a four-foot riser with a ladder up the side; the other is a 6-foot riser with a platform, ladder and railing system. Most risers are manually tiltable for transport. The cab risers are almost always equipped with a safety window guard to protect the operator from large pieces of material that may come back into the window. The riser should meet requirements commonly found in most safety codes, including:

¡ñ            minimum distances between steps

¡ñ            adequate grab handles positioned in a way that allows operators to have a three point stance, and

¡ñ          a kick plate around the edge of the platform to prevent a mechanic from kicking off a tool and injuring a co-worker.

CONVERTING TO SUIT

It would be difficult to argue against the notion that the primary benefit of conversion models is their affordability. After all, processors can attempt to perform their own conversions at the cost of parts, labor and the price tag on the pre-owned excavator.

Even when buying from conversion specialists, newly-converted scrap handling cranes can be purchased for from $40,000 to $80,000. This is well below the $200,000 price tag often encountered with new purpose-built machines.

But conversion specialists are beginning to look beyond selling on price alone. ¡°I put what is called a satisfaction warranty on my machines,¡± says one converter. ¡°The warranty is on the boom and arm if we re-do them, plus the engine, the hydraulic system, the pumps and motors,¡± he notes.

The conversion specialist also consults with buyers up-front on such things as the platform and attachments that will best suit their operations. It is a way of bringing some customization into the conversion process and is possibly a key in opening up broader markets for converted machines.

¡°Some guys simply can't afford a $200,000 machine¡ªthe decision is made for them,¡± says the conversion specialist. ¡°But even for the people who do have the funds to devote $200,000, there is a segment who need to stop and give pause in their purchasing consideration to a properly-done conversion.¡±

He notes that purpose-built machines do indeed have an edge in their lifting capacity and range of reach, but believes that not all applications require that extra capability. ¡°You're paying $80,000 instead of, say, $250,000¡ªthere are going to be some rational trade-offs. That could be capacity or it could be reach or a combination of the two. But the savings opportunity is tremendous.¡±

The author is managing editor of Recycling Today.

SAFETY FIRST

Whether operating a purpose-built or converted scrap handler, scrap processors need to be aware of several safety issues and be familiar with existing safety codes and practices.

The American Society of Mechanical Engineers (ASME), Fairfield, N.J., is developing a safety volume (B30.25) entitled Scrap and Material Handlers, that covers the topics touched on above as well as several others. According to engineering advisor Joseph Pang, who is secretary for ASME's B30 Committee (the Committee on Safety Standards for Cableways, Cranes, Derricks, Hoists, Hooks, Jacks and Slings), the standards should be published later in 1998. Those interested in finding out more about the scrap handler safety standards can contact Pang at the ASME at (212) 705-8522.

Both the ASME and the Institute of Scrap Recycling Industries Inc. (ISRI), Washington, have materials available addressing safety issues associated with the operation of scrap handlers and other heavy equipment. The purchasing stage marks a logical time to begin the consideration of safety issues to minimize the risk of injury to the machine's operator and nearby workers.