Ball roller BUSH 30

A 30 mm steel ball in a housing with a 14 mm overall height: BUSH 30 is the ball roller you choose when a packing table, tool change table or transfer table has to be able to move goods in all directions without the table growing in height. Unlike a roller conveyor, which leads the goods one way, a table with ball rollers lets the operator push, turn and rotate the load freely; that is why ball tables are standard at manual stations where heavy blanks have to be positioned exactly.

The load capacity is 200 kg per unit dynamically, stated at 4 km/h. In a finished table you always spread the load over several ball rollers, and a proven rule of thumb is that the goods should rest on at least three balls at once. Otherwise point loads arise that can leave marks in the underside of the goods, and the movement becomes jerky as the load tips between single balls. With 200 kg per ball the capacity goes a long way even for molds, sheet metal blanks and heavier machine parts.

The dimensions from the manufacturer's data sheet: ball diameter 30 mm, outer diameter 44.5 mm, collar diameter 55 mm and a material thickness in the plate of 4 mm. The net weight is 0.36 kg per unit. The temperature range runs from -30 °C to +70 °C, and the unit is not rated as heat resistant beyond that; if the table is to stand next to a hardening furnace or another hot process you need to look at other versions.

In Swedish workshop industry this type of ball roller typically sits in tool change tables at presses and injection molding machines, where tools weighing several hundred kilos are to be pushed into position by hand. It is used in leveling tables for sheet metal work, in inspection stations where parts have to be turned without lifting and in transfer zones in warehouses where cartons and crates change direction between conveyors. At packing stations the balls let the operator spin the goods around while it is taped and marked. What all the cases have in common is that the ball takes away the friction between goods and table, so the weight is moved with hand force instead of with the back.

The mounting is a drop in type. The unit is lowered into a cut out in the table top and the 55 mm collar rests against the surface around the hole. Take the hole diameter and tolerances from the data sheet before you drill; it is cheaper to check once more than to redo a whole hole pattern. Think about the spacing as well. The distance between the balls is chosen by the smallest base dimensions of the goods, so at least three balls always carry wherever on the table the load ends up.

If you are choosing between the drop in version and ball rollers with a threaded stud it is mostly about the base. Drop in mounting gives the lowest total height and a smooth table surface, but requires you to be able to make holes to the right dimensions. Stud mounting is easier to fit afterward but builds higher. For fixed tables in a production environment the drop in version is usually the more durable and easier to clean choice.

The ball is in steel and wants a reasonably clean environment. Chips, grinding dust and packaging residue packed around the ball increase the rolling resistance and wear on the ball seat, so blow the table clean at regular intervals. A sticking ball is felt immediately in the hand force; replace it before the operators start to compensate with unhealthy working postures.

Are you thinking about the hole pattern, the spacing or how many ball rollers your table needs? Get in touch and we will work it out together.