Bearings for sintering and pelletizing plants

Sintering is a crucial phase in the steelmaking process where iron ore is prepared for subsequent melting in furnaces.

The bearings (pressure rollers and support wheels) present in sintering and pelletizing plants are subject to heavy loads, relatively low speeds, and high temperatures. These elements create an extremely challenging operating environment characterized by the presence of abrasive particles that can compromise lubrication and cause premature damage.

The pressure rollers are fundamentally derived from full complement double row cylindrical roller bearings (fig. 1).

In some cases, they may be full complement four-row cylindrical roller bearings (fig. 2).

The outer ring, which is very thick, has three integral flanges. It also has a diametrical outer surface that is highly resistant to wear, cylindrical in shape, with chamfers or fillets at the ends. The inner ring is in two parts, each equipped with an integral flange, designed to withstand the strong axial loads that accompany the radial loads. The O-rings inserted in a special groove of the inner ring flanges make the bearing non-disassemblable and prevent the entry of contaminants from the outside and the leakage of lubricant.

These units, already ready for assembly, are also suitable for all applications where there are high loads and the direction of rotation often reverses, or there are low speeds.

Originally, the pressure rollers had been designed for use on the continuous furnaces of sintering and pelletizing plants (fig. 3).

The mineral agglomeration furnaces are fed by a continuous chain of carts.

The carts run on rails and are guided by support wheels with a side edge.

The movement is transmitted to the carts by two gear wheels located at the end of the conveyor, which mesh with the pressure rollers that are most subject to fatigue.