NADELLA GCR47 EEMSW Laufrollen (20x47x25,6)

As a track or cam roller, this component runs directly on a mating track or cam surface. At 20x47x25.6 mm and a unit weight of 0.5 kg, the installation envelope is fixed; further technical details are held in the specification table. The thick-walled, hardened outer ring still carries the contact pressure from the contact with the track. This track roller is metallically sealed on both sides.

The decisive difference from a polymer version lies not in the sealing effect itself but in the boundary conditions under which it is retained. A metallic element keeps its form and its strength even when the bearing position runs hot or when oils, cutting fluids and cleaning agents are present directly; an elastomer, under the same conditions and depending on the material, loses strength, swells or hardens, and the contact of the seal lip recedes with it.

For track rollers on hot tracks, in furnace areas, on oil-wetted guides or in chemically loaded surroundings, that is the reason for this choice; the governing limits are those of the lubricant and of the size, and no longer those of a seal material. The counterpart is to be named just as plainly: a metallic seal does not close the rolling chamber as completely as a bearing lip, so a lower protective effect is to be expected against fine, continuously arising dust and against standing water.

The load-carrying construction remains unchanged: the thick-walled outer ring, hardened through the running depth, rolls directly on a rail, a profile or a track and rotates through the load, so that the most heavily stressed location travels over its circumference; the hardness, surface finish and course of the mating track belong to the layout and limit the pairing regardless of the size. Rings and rolling elements are made of standard bearing steel.