Conveyor basics

Conveyor basics

Here's both a refresher and an update on the wheel, belt, roller and chain conveyor commonly used to transport products through industrial facilities.

By Corinne Kator, Associate Editor -- Modern Materials Handling, 12/1/2007

• Non-powered conveyor
o Skatewheel conveyor
o Roller conveyor
• Powered package-handling conveyor
o Beltconveyor
o Roller conveyor
▪ Line-shaft conveyor
▪ Chain-driven roller
▪ Belt-driven roller
▪ Motorized roller
o Segmented belt conveyor
• Powered pallet-handling conveyor
o Chain conveyor
o Pallet-handling roller conveyor
• Over-sized conveyor
Visit a modern distribution center ormanufacturing facility and you're likely to find miles of different kinds of conveyor moving cartons, totes, pallets, components, work-in-process and finished goods from one area of the facility to another.
Conveyor has been a staple in materials handling for decades. It's available in many styles and is used in countless applications. In this article, Modern spotlights some of the most commonconveyor types:
• Non-powered skatewheel and roller conveyor
• Powered belt and roller conveyor used in handling packages and other small products
• Powered chain and roller conveyor used in handling pallet loads of goods

Non-powered conveyor

The simplest form of conveyor—non-powered conveyor—uses the natural forces of inertia and/or gravity to keep products in motion.
Portablesections of non-powered conveyor are often used for loading packages into the back of an over-the-road truck. Non-powered conveyor can also serve as takeaway conveyor for cartons coming out of an automated sorter, and it's often used in workstations and in pick modules where employees complete their tasks and then push their work along to the next zone or station.
The two most common types ofnon-powered conveyor are skatewheel and roller.

Skatewheel conveyor

Little energy is needed to turn the small wheels of a skatewheel conveyor, and that makes skatewheel good at maintaining the speed of a product, says Tim Kraus, conveyor product manager for FKI Logistex (877-935-4564, www.fkilogistex.com). Because each wheel turns independently, he adds, skatewheel conveyor is also a good choicefor the curved sections of a conveyor line.

Roller conveyor

Non-powered roller conveyor is commonly used for workstations and pick modules because it provides a better working surface and is often less expensive than skatewheel conveyor. It's also good at slowing the inertia of products coming out of a high-speed sorter.

Powered package-handling conveyor

When it comes to moving packagesand other relatively small items, two styles of conveyor dominate the market: belt conveyor and roller conveyor.
Traditionally, says Ken Ruehrdanz, market development manager at Dematic (877-725-7500, www.dematic.us), belt conveyor has been used for transporting products, while roller conveyor has been used for accumulating products. Recent advances in technology, however, are blurring that line.Belt conveyor

In traditional belt conveyor, an AC motor drives a pulley that then turns a long, looped belt. The belt can be made of a variety of materials, depending on the items it's intended to convey. Underneath the belt sits either a bed of non-powered rollers or a sheet of metal known as a slider bed.
Traditional belt conveyor is a simple, time-tested technology. It's less expensivethan powered roller conveyor, it provides a more stable conveying surface, and it can convey a wider variety of products, says Ruehrdanz. Poly bags, envelopes and electronics are examples of products handled easily by belt conveyor that are often too small or too light to be conveyed directly on rollers.

Roller conveyor

Despite the advantages of belt conveyor, many of today's distribution...