The rollers on a conveyor are mounted either above or below the frame. Most conveyors ordered from A Plus Warehouse are set high, because otherwise if a load overhangs the rollers its path will be blocked by the frame. A roller conveyor with rollers set high will allow users to move items slightly wider than the nominal roller length, while a low-set roller conveyor’s frame can be used as a guard rail to ensure loads remain on the conveyor.
The roller center of a conveyor is defined as the distance between rollers (center to center) on the conveyor. The minimum number of rollers required for a rigid package is three, and flexible packages require four rollers. To measure how large of a roller center is required, materials should be measured and then divided by three for rigid packages or four for flexible packages. The resulting measurement is the length of roller center you will need.
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