Support rollers with flange rings

Support rollers with flange rings are non-separable units, designed for applications where there are axial loads, but no lateral (axial) support surfaces (fig. 1). These axial loads, which are induced when shafts are not horizontal or aligned properly, are accommodated by the flange rings. Depending on the design of the support rollers, the flange rings are pressed-on (NATR and NATV designs) or loose (NUTR, PWTR and NNTR designs).

NATR and NATV design support rollers

NATR design support rollers (fig. 2) are fitted with a needle roller and cage assembly, while NATV design support rollers (fig. 3) have a full complement of needle rollers. The outer rings of both designs are guided axially by pressed-on flange rings. The narrow gap between the flange rings and the outer ring serves as a gap-type seal.
Both designs are also available with an axial sliding ring on both sides, identified by the designation suffixes PPA (fig. 4) and PPXA. The axial sliding rings are made of PA66. In the radial direction, the sliding ring forms a narrow labyrinth seal with the outer ring, to protect against coarse contaminants. In the axial direction, the sliding ring serves as a contact seal to reliably retain grease in the bearing. This improves the lubrication conditions in the bearing, keeps friction and frictional heat low, and extends grease life.
Support rollers with axial sliding rings can accommodate somewhat heavier axial loads than those without axial sliding rings. Axial loads are induced when operating in an inclined or tilted position.

NUTR .. A design support rollers

NUTR .. A design support rollers (fig. 5) are based on double row, full complement cylindrical roller bearings without an integral flange between the two roller sets. The outer ring has two integral flanges to guide the roller sets axially. A loose flange ring on both sides of the inner ring provides axial guidance for the outer ring via the roller sets. This enables NUTR .. A design support rollers to accommodate relatively heavy axial loads that are induced when operating in an inclined or tilted position.
A sheet metal angle ring is pressed into the outer ring shoulder on both sides and forms an effective labyrinth seal. The angle rings extend over the flange rings, making the bearing non-separable.
If heavy shock loads occur, support rollers with a reinforced outer ring should be used. These are identified by a bearing designation that has a four- or five-digit number instead of a two-digit number, e.g. NUTR 50110 A.

PWTR ...2RS design support rollers

PWTR …2RS design support rollers (fig. 6) are based on double row, full complement cylindrical roller bearings. Three integral flanges in the outer ring guide the two roller sets axially. A loose flange ring on both sides of the inner ring provides axial guidance for the outer ring via the roller sets. This, together with the relatively large grease quantity between the two roller sets, enable PWTR …2RS design support rollers to accommodate relatively heavy constant axial loads that are induced when operating in an inclined or tilted position.
PWTR ...2RS design support rollers are supplied with an NBR contact seal on both sides. The seals are integral with the sheet metal angle rings and press against the flange rings. The angle rings are pressed into the outer ring shoulder. They extend over the flange rings, making the bearing non-separable.
If heavy shock loads occur, support rollers with a reinforced outer ring should be used. These are identified by a bearing designation that has a four- or five-digit number instead of a two-digit number, e.g. PWTR 50110.2RS.

NNTR ...2ZL design support rollers

NNTR ...2ZL design support rollers (fig. 7) are based on double row, full complement cylindrical roller bearings. They are designed to accommodate very heavy radial loads. Three integral flanges in the outer ring axially guide the two roller sets. A loose flange ring on both sides of the inner ring provides axial guidance for the outer ring via the roller sets. This, together with the relatively large grease quantity between the two roller sets, enable NNTR ...2ZL design support rollers to accommodate relatively heavy constant axial loads that are induced when operating in an inclined or tilted position.
NNTR ...2ZL design support rollers are fitted with a lamellar seal on both sides. The seals are inserted into recesses in the shoulders of the flange rings and the outer ring, making the bearing non-separable.
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