They must be durable, long lasting and resistant to a wide range of temperatures, moisture and chemicals.
There are five main materials that conveyor belts are made out of: thermoplastics, metal, rubber, fabric and leather. Plastics include polyester, polyvinyl chloride, silicone and polyethylene. The metals are stainless and carbon steel, and the fabric materials are canvas or cotton. The most popular material is a rubber composite because it is flexible, resistant, smooth and seamless.
It also doesn’t have any holes or openings. To increase strength, many belt materials contain additives, including fabric, steel, polyester or fiberglass. Many flat belts are actually composed of a core material and a covering. These belts are parts of many different types of conveyors, including troughed, inclined, horizontal, food grade and overhead conveyors, but they are not used in chain, pneumatic or screw conveyors.
Choosing the right belting material is the most important specification involved with conveyor systems because the wrong material could compromise productivity or worker safety.
Conveyor systems, especially those in manufacturing facilities, travel through many different environments. For example, assembly line conveyors may travel through an oven, underwater parts washer or some sort of secondary operation like painting. Therefore, they must be resistant, durable and able to handle these harsh conditions on a continuous and regular basis.
Belts that carry ingredients, raw materials and finished, unpackaged goods in food or beverage processing plants are made of either stainless steel or a heat resistant, non contaminating plastic resin. They must be FDA or USDA approved and easy to clean and sanitize. Materials like some hard plastics or metal lack the flexibility needed to convey, which requires the belt to bend, as they are on a continuous loop around two sets of rollers.
In these situations, small parts are interlocked together or woven in order to bend and twist. However, these tend to have holes or cracks and are not smooth or water tight. They are not made for carrying small or irregularly shaped objects as well as products in bags, which could sag or fall through the cracks.