Ball roller BUTM 16

Sometimes a rolling point just has to be bolted down and work. BUTM is a ball unit with a steel ball mounted on a sheet metal plate with a ready made hole pattern; you drill to the dimensions of the plate, tighten the screws and have a carrying ball point in place. No press fit and no tight hole tolerances, and if the station has to be rebuilt you move the unit in a few minutes.

The plate measures 33x50 mm and is made in 0.8 mm sheet. The screw holes have a diameter of 4 mm and sit at a c/c distance of 40 mm. From the base to the top of the ball the overall height is 21 mm, and the outer diameter of the ball housing is 28 mm. The manufacturer states the load capacity as 15 kg per unit at 4 km/h. The temperature range runs from -30 °C to +70 °C, so the unit works just as well in a chilled warehouse as in a hot summer workshop, and the net weight is 0.04 kg.

The basic rule for all ball units is the same: the goods must always be carried by at least three balls. Start from the smallest base dimensions of the goods when you decide the spacing between the units, and then check that the load spread over the balls that actually carry stays under the load capacity per unit. Count on a margin; a box set down at an angle loads the first ball harder than the average, and it is that shock that decides the service life.

The screw mounting makes this model the standard choice when balls are to sit on steel frames, work benches or machine frames. In Swedish industry they turn up at infeed tables, as turning points in packing lines, on the inspection table in goods reception and in assembly stations where parts are pushed between operations instead of being lifted. If the flow has to change the units are unbolted and put up in the new layout; that reuse is one of the points of plate mounting.

The placement follows the same logic as the layout as a whole. On straight runs the units sit in rows with even spacing; at turning points the pattern gets closer so the goods always have support through the whole turn. It is worth sketching the hole pattern on paper or in CAD before you drill, since it takes ten minutes and saves redrilling. And do not forget to check that the base is flat; a skewed beam gives balls that do not carry and goods that pull to one side.

If you are choosing between plate and drop in mounting the guideline is simple: drop in when the ball is to be integrated into a sheet that is going to be cut anyway, plate mounting when you are building on existing tables, frames and racks without major work. The plate also spreads the load over a larger area, which is kind to thinner table tops.

Without a motor and without electricity the running cost is in practice zero. What remains is simple care: keep the balls free from chips, dust and packaging residue and the rolling resistance stays low. The goods need a flat and stiff surface to bear against; cartons with a soft base or parts with grooves in the underside roll worse and can catch. A dry indoor environment is home ground for the steel ball, so wet or corrosive environments are worth checking with us first.

Complete dimension sketches, material data and fitting instructions are in the manufacturer's data sheet. The series covers several sizes with rising load capacity, and mixing sizes in the same station works well if the load cases differ between the positions; the hole patterns are small and easy to place close together where they are needed.

Do you want to discuss load cases or the hole pattern before you order? Get in touch with us.