Load rollers; selection load roller, roller length and pitch

Selection of load roller
The following points are important in the selection of a load roller:
- dimensions and weight of the product to be transported;
- the kind of packaging around the product to be transported (box, case, crate, pallet, loose, etc.);
- contact surface of the packaging or the product (hard, soft, straight, round, etc.);
- environmental conditions (moisture, dust, temperature, etc.);
- special requirements (antistatic, low noise, etc.);
- transport conveyor type (gravity conveyor, powered conveyor, belt conveyor, etc.)

Selection of roller length
Roller lengths greater than 1.25 to 1.3 times the width of the product are not generally used. This is to prevent an unacceptable point load. The load capacity at a point load is 60% of the values given in the diagrams.

Pitch
To transport a product without any problems, there should be at least three load rollers under the load-bearing surface of the product: the maximum pitch is the product length divided by three. If the load in the box, case or crate is unevenly distributed, a smaller pitch must be chosen. The same is true if the height of the product is more than twice its length.
If the contact surfaces are soft and slack and the pitch is too large, then the product will tend to droop down either side of the roller tube, which will increase the drag forces. This can largely be prevented by reduction of the pitch.

L = length of the product to be transported
H = height of the product to be transported
S = pitch or separation between two rollers