“We experimented with this body in different versions and we were convinced that it has undeniable advantages compared to the sphere. The sphere has already reached the ceiling of its abilities and has exhausted its potential. With it - we can only change the size, the material and the outer surface. This however is too insufficient and ineffective today. In the production of the traditional spheres, expensive materials are used which allow to quench with hardness to the center and the best possible manufacture, but this is it - no more development. And that has continued for 152 years. The tetrahedron undoubtedly has greater opportunities. Aside everything applicable for the spheres, with it we can make flat, convex, curved, round and concave edges. And after numerous experiments and tests we have found that different variations affect differently the different materials for grinding. So we came to the conclusion that any material has optimally shaped form of RELO Grinding Body. “

 Engineer Petar Bodurov – the inventor


The RELO products demonstrate indisputable advantages in every aspect. Their specific shape leads to a RADICAL change in the processes of grinding in the drum mills.

Some of the most significant advantages of the new shape result from that it has from 6 to 12 symmetrically arranged arcuate edges, four rounded vertices, a lower center of gravity, a larger surface for grinding, a larger contact surface and more sloping spherical sides. These basic differences with the sphere ranked it as the undisputed challenger and gave it a number of important advantages over the other, such as:

• Bigger kinetic force of the blow when falling on the material, for better crushing and grinding, thanks to the larger contact surface and the lower center of gravity which facilitate the higher ascent of the bodies in the mill.

• More than 6 arcuate edges with maximum effectiveness with incline of 120 degrees and 4 vertices, helping to increase by 100% the efficiency in crushing.

• Larger and more sloping side for grinding, which doubles the milled material for the same time.

• Increases by about 10% the quantity of fine-grained particles under 75 microns, which contributes to the increased extraction of the valuable particles during the flotation process.

• Thanks to the lower center of gravity, the tetrahedrons in the mill are positioned with their round side to the surface of the mill, thereby they are not damaging the inner coating.

• The tetrahedron has a shape with discontinued width and edges, unlike the sphere, and this helps to better quenching with over 60%.

These basic advantages and characteristics of the new body directly affect significant advantages and benefits of the production and consumption of this product.

On the first place, we set the increased by over 97% productivity of the mill, thereby reducing by over 40% the costs for electricity for grinding per each ton of material, but also reducing to half the time for grinding the same amount. At the same time the finely grinded particles are increased by about 10% and the wear resistance is increased over three times.

Other significant advantages for producers and users are:

• The mass quenched is over 60% more than the same of the sphere, which leads to increasing more than three times the wear resistance during operation and allows the use of inexpensive manganese steel and heat treatment technologies. Thus savings of expensive materials used to better quenching during their production are effectively achieved;

• The form also allows greater compactness by about 15% depending on the sizes. Which besides reducing the cost of transportation and storage, is a direct way to increase the efficiency of grinding, as it allows to add 10-15% more bodies in the mill;

 Zero investments in putting into operation - without additional investments or time to put into service. May be added in the ball mills together with the conventional consumable until complete replacement without stopping the production processes;

• Improved self-cleaning - without expenses of cleaning chemicals;

• Without special training of the staff for production and operation;

• Suitable for comminution of the coarser particles;

• Improved dry grinding;

• The technology of the RELO bodies allows grinding by comminution - also suitable for grinding of elastic materials;

• Design, compatible with mass production - suitable for production by traditional methods such as casting, rolling, forging;

• Higher quality production by casting compared to the conventional products – the gas abscesses are concentrated in the center of the bodies;

• Reducing the energy consumption in grinding is accompanied by reducing the amount of fuels burned, which are the main source for electricity production and in parallel reduce the sulfur compounds, nitrogen and carbon oxides etc. discharges into the atmosphere;

 Various derivatives designs specialized in the processing of different types of ores.