A roller conveyor is a conveyor that consists of a series of parallel rotating bars that move goods along to their end destination. Roller conveyors are used in environments like warehouses and manufacturing facilities. They can also be fitted inside certain types of equipment, such as tortilla machines that produce tortillas automatically and run them down a roller conveyor to allow them to cool after they are made. Likewise, manufacturing of some types of candy often involves a roller conveyor for cooling.
The design of a roller conveyor consists of a series of tubes mounted at set intervals. The tubes rotate at the same rate and in the same direction to push objects along the top of the conveyor. Setting the conveyor at an angle can also help to propel objects along. The device may have equipment located alongside to perform various functions such as sealing packages, and employees can also be stationed along the conveyor to manipulate objects as they pass by.
One disadvantage to the roller conveyor is that objects can fall through the rollers or be awkwardly shaped and sized and thus not move along the conveyor very well. An ideal application for this kind of equipment is on packaging lines, where boxes of uniform size and shape can move easily down a roller conveyor. Likewise, when air circulation around a product is needed as it moves down the line, as seen with candies, the roller conveyor can be very useful.
This type of conveyor system relies on a blend of gravity created by the angle of the belt and propulsion from the moving rollers. Maintenance of roller conveyors requires periodically cleaning the bearings used for rotation to ensure that the rollers are smooth, and checking for signs of leaks and soiling on the bars themselves. On a candy production line, for example, the rollers can become gummed up with chocolate coating and other materials and they may stop freely moving, bringing the conveyor belt to a halt.
Like other manufacturing equipment, a roller conveyor can be dangerous for unwary employees. It is possible to catch and mangle extremities in the rollers, and people with long hair are usually advised to keep it secured under a work cap so that it does not become caught. When the line needs to be maintained, the conveyor must be turned off and the use of a switch lock to prevent someone from accidentally turning the conveyor back on is recommended.