Belts and rollers: which to use and how to specify
27th June 2019
Belt conveyors move along a surface beneath the belt (plastic strips, metal slider pans or rollers), and are pulled along by a drive pulley that’s equal to the belt width. Belts can be specified to do most any job, and are particularly good for conveying boxes/cartons, irregular items, and more fragile loads that require more support than rollers. Bags or looser components are often conveyed on belts. Belts are the default conveyor type for incline conveyor applications.
The type of belt depends on your application.
“Everyday” general purpose belts are made from a variety of materials (Nylon, PVC, rubber, etc) and lots more. They are good for warehouse systems in predictable conditions. Some of these belts can be made in food-grade materials, others for high temperature applications, bulk/trash conveyors, accumulation systems, and as mentioned above, for incline/decline conveyors. Most belt conveyors you will see fall into the general purpose range.
Plastic belts/chains are built for specific applications, such as medical/pharmaceutical, wet areas, packaging, sanitary areas, machine integrations, and food handling. Many of these systems can be washed down for clean applications. These types of conveyors are often specified as low profile (or “table top”) systems. They’re considered a lighter weight conveyor, but are very wear resistant and can fit into tighter spaces.
Metal belts: These belt types are typically used in bulk, manufacturing, high-heat, washdown, stamping, and similar operations. They can be specified in hinge, woven wire, or flat belt configurations.
live roller conveyor
Roller conveyors are used for general conveying applications. They are more demanding than belt systems are in terms of load quality—they usually can’t handle inconsistent, sagging, or damaged loads, as load irregularities will sag or tilt. Heavier items may bounce or roll. Rollers are ideal for diverts or package stops where “blades” can raise between a couple of rollers to stop or divert a load. This versatility is key at traffic points, where you often find roller systems. Rollers can be skewed to easily divert loads as well. Rollers can also be made in “bowtie” style to create a cradle to transport pipe, tubing or similar loads.
Rollers are versatile in that you can also create very heavy-duty applications. Standard rollers are 1.9″ diameter, but you can get them in 2.5″, 3.5″, or even larger sizes to move extremely heavy loads in manufacturing or processing applications. Roller can increase or decrease the space between (called “roller spacing) to hold even more weight as needed. Usually a single item requires 3 rollers beneath it for smooth conveying, but more is sometimes needed, and rollers allow you to do that.