Purchasing Conveyors—Carry Me Away

July/August 1993 

BY NANCY L. GAST

Nancy L. Gast is editorial associate of Scrap Processing and Recycling.

SF seeks reliable, versatile object of affection to help me through the days and nights. Searching for rugged hard worker with a stable upbringing and clean looks. Long-term relationship desired.

Love at first sight has been known to happen. Still, finding a perfect match can be a challenge—especially when SF stands for scrap facility, and the object of pursuit isn't tall, dark, and handsome (at least not in a strictly conventional sense), but the conveyor of its dreams.

Making the right choice when it comes to buying conveyors may not be quite as critical as finding someone to spend the rest of your life with, but the stakes are high nonetheless. When a plant/conveyor relationship goes sour, for instance, the result can be costly downtime, high repair bills, and/or reduced efficiency. So, if you're looking to buy a conveyor system and need some help making the decision, check out the advice of the conveyor makers here, who reveal what no scrap recycler can afford not to consider when conveyor-shopping—no matter which manufacturer you choose to do business with.

You know your needs. You know the size of our operation, the type and quantity of scrap you handle, and the business you're looking toward in the future. That's the first step in choosing the right conveyor. And, elementary as these specifications may seem, don't take for granted that they'll be assumed by your salesman. Dan Bowman, vice president of marketing for Simplicity Engineering Inc. (Durand, Mich.), says that some conveyor-shoppers don't speak up with that kind of vital information. "Many times," he says, "we've seen people with vague ideas of what they want." Different manufacturers, he warns, respond to vagueness in different ways. The result could be a machine that's really too rugged—and expensive—for your operation's requirements, or, perhaps even worse, a lightweight model that won't last you a year.

So deluge your manufacturer with details. After all, virtually every conveyor maker surveyed emphasizes that it builds its conveyors to order. "The more information you have to work with, the better," asserts Mike McLemore, executive vice president of Central Manufacturing Inc. (Peoria, Ill.). In a pinch, he adds, "sometimes illustrations on dinner napkins suffice."

Beyond the basics, there are plenty of other factors buyers don't always ask about—and should, according to manufacturers—that could make the difference between a short-term fling and a long-lasting conveyor/plant relationship.

• Made for each other. What kinds of equipment do you operate? Many manufacturers boast that their product will fit in with virtually any other equipment in your plant. But others, like MAC Corp./Saturn Shredders (Grand Prairie, Texas) and Texas Shredder Inc. (San Antonio), emphasize that buying conveyors produced by the same manufacturer that made the equipment the conveyor will work with alleviates many potential problems right off. "The biggest problems I've seen people have is when the conveyor doesn't fit in with other plant equipment," Texas Shredder's Jim Schwartz, vice president of engineering, reports.
  

• Stand by me. While major changes may hurt a human relationship, it's a fact of life in the scrap world. When money's at stake, that means adding profitable scrap to your operation, and/or discontinuing dealing with the stuff that just isn't paying. So will your conveyor be able to keep up with the times? Jim Sullivan, president of Triple/S Dynamics Inc. (Dallas), says that it's "crucial to inquire about changing load types and weights, because some conveyors will stop working" if they're used to move materials other than those they were designed for.
  

• Practice safe ... habits. When you buy a conveyor, you're not just dealing with machinery. You have to take the people who work with or near the conveyor into consideration as well, which translates to attention to safety features.
  

At a minimum, this means stipulating a conveyor design that meets federal, state, and local safety regulations. Relatively new Occupational Safety and Health Administration (OSHA) requirements, for example, basically mandate that any part of a conveyor that's going to be close to people has to be guarded. Traditionally, that applied to the head and tail pulleys and the drive system, but nowadays, it's every roller over the entire length of the conveyor, explains Schwartz. Texas Shredder's solution: Practically all of its conveyors are now made semi-flat instead of in the old "troughing" design, which cuts down on the need for extra guards. "We guard everything on the machine that's under 7 feet—and that protects everyone but a few NBA players," Schwartz jokes.

• The strong, silent type. We're talking about a heavy-duty machine for a heavy-duty operation, right? So noise is to be expected. Don't be too sure—OSHA has regulations for that, too. OSHA mandates that in scrap plants of certain sizes, noise—both decibel level and frequency ranges—has to be kept under control, so you'll want to include this requirement in your buying specs. And even if OSHA didn't demand it, you should pay attention to the noise levels of any conveyors you're considering, advises Bill Graveman, president of Magnatech Engineering Inc. (Tonganoxie, Kan.). In a well-made machine, he says, there aren't a lot of "clanging metal parts, which waste energy. A quiet machine is a sign of quality of design." So silence really is golden.
  

• Wham! Bam! Ala-kazamm! Have you taken possible explosions into consideration? If you're running materials subject to explosions, you might want to consider mounting pan feeders on pan springs. According to Bowman, this creates a "cushioning" effect that lessens the severity of most blasts.
  

• Don't get zapped. Don't assume that the manufacturer will assume where you conveyor is to be installed—indoors or out. "If it's outdoors," Graveman stresses, "be sure that workers can't be electrocuted in a lightning strike during rain or other inclement weather."
  

What happens when the honeymoon's over, and your conveyor needs some extra attention? That's when the manufacturer's maintenance policies come into play—policies that affect the rest of your conveyor's life.

Because conveyors lead such a rough-and-tumble life, even the sturdiest models need at the very least an occasional check-up. Will the manufacturer be around to pick up the pieces? While the manufacturers surveyed didn't see eye-to-eye on some aspects of conveyor shopping, they all agreed that service is, as Hustler Conveyor Co.'s (St. Louis) vice president, Paul Griesedieck, puts it, "the most important thing you can give your customers."

What does service mean to different conveyor-makers? To some, it's being available all day, every day. Many will send one of their repairmen right to your plant within 24 hours. Service hotlines—800-numbers complete with experienced repair engineers on the other end—are another method of keeping the customer happy. If a particular service strategy is important to you, let the manufacturer know up front—before you've made an investment in your conveying system.

When it comes to replacement, most manufacturers stress that their parts are available for speedy delivery—which should mean less downtime for you. But when it comes to the type of replacement part they recommend, there are two schools of thought.

On one side are companies like Mayfran International (Cleveland), which proudly points out that every part of every conveyor it makes is manufactured in-house—from the belts and chains to the rollers and belts. According to Dick Merrill, the firm's vice president of sales and marketing, this means quality control. "When you put one of our systems in," he says, "there's no one else to point at except Mayfran."

Manufacturers such as Texas Shredder and MAC /Saturn think otherwise, nothing that using some nationally available components in their conveyors enables customers to easily get replacement parts, no matter where their operations happen to be located.

Of course, an article like this one no more assures you of buying the ideal conveyor for your plant than the personal ads guarantee you a mate, but reviewing some of the basic questions and knowing what's out there can help narrow your search a bit.

So do your homework. Let manufacturers know you're not after a one-night-stand—or even a one-year stand. Make your intentions clear, and in return, you won't wake up a few months or years down the road, wondering just who that conveyor in your plant really is.

And just maybe you and your conveyor will live scrappily ever after.

Conveyors are, of course, adaptable. How else could the same idea—a belt wrapped around spools—handle everything from a cartful of groceries to a planeful of luggage to scrap of all shapes and sizes? But not all conveyors are appropriate for all kinds of jobs. Here's a quick introduction to the major types of conveyors used in scrap processing facilities.

• Vibratory conveyors are made for picking, sorting, and cleaning loads as well as conveying, using a flexibly supported, spring-mounted pan that vibrates mechanically, electrically, or pneumatically. Metal scrap—particularly bulky demolition scrap—is conveyed by a sort of "throwing and catching" action.
  

• Oscillating conveyors work in a similar fashion to their vibrating cousins, but while vibratory conveyors vibrate randomly, with an oscillating conveyor, you can actually define the movement around the material and the desired speed. The machine's drive mechanism transmits an oscillating, or swinging, motion to the pan, which results in quick forward and return strokes that serve to move the scrap along. It's a good choice for not-so-bulky shredded or sheared scrap.
  

• Steel belt conveyors are made up of a moving series of steel surfaces that are connected by hinges. While they're good for transporting a wide variety of scrap, watch out for fines that may catch in the hinges and wings, causing jam-ups.
  

• Magnetic conveyors have a magnetic field that causes ferrous scrap to move along a stainless steel faceplate or belt.
  

• Natural frequency conveyors have spring-massed systems and move with a simple harmonic motion. Overly heavy loads tend to detune this model, so manufacturers recommend that they operate under certain load limits.
  

• Differential motion conveyors work with a forced vibration system without springs, generating a quick-return motion that makes it possible to move material without any pitching action. Therefore, it's well-suited for handling heavy loads.
  

• Stacking conveyors are space-savers. Although widely employed overseas, they've seen limited use in the United States . Nevertheless, Mayfran's Merrill believes they'll soon gain popularity here, particularly in the Northeast, where industrial property for scrap plant use is quickly diminishing. Stacking conveyors can both segregate material as well as load it into railcars or trucks afterward.
  

• Pneumatic conveyors transport particles of solids through a pipe, using air or other types of gases as a carrier.
  

• The name apron and pan has nothing to do with the kitchen—rather, with the design of this type of conveyor. Overlapping horizontal plates known as aprons are attached to chains to form a bed for carrying materials. When the aprons have vertical side plates, they're called pans.  —N.L.G.

Looking for the conveyor of your dreams? Some major manufacturers fill you in on how to find your perfect match.