Designation system

The designations of most SKF rolling bearings follow a system that may consist of a basic designation with or without one or more prefixes and/or suffixes (→ Basic bearing designation system).

An example and the applicable options for support rollers are given below.
Basic bearing designation system
NATR 5 PPA
whereNATR 5 =
PPA =

Prefixes (n.a.)


Basic designation
NA 22
Support roller without a flange ring, fitted with a needle roller and cage assembly.
STO
Support roller without a flange ring, fitted with a needle roller and cage assembly.
NATR
Support roller with two pressed-on flange rings, fitted with a needle roller and cage assembly.
NATV
Support roller with two pressed-on flange rings, fitted with a full complement of needle rollers.
NUTR
Support roller based on a double row, full complement cylindrical roller bearing with two integral outer ring flanges and a loose flange ring on both sides of the inner ring.
NNTR
Support roller based on a double row, full complement cylindrical roller bearing with three integral outer ring flanges and a loose flange ring on both sides of the inner ring.
PWTR
Support roller based on a double row, full complement cylindrical roller bearing with three integral outer ring flanges and a loose flange ring on both sides of the inner ring.


Suffixes - Internal design (n.a.)


Suffixes - External design (seals, snap ring groove etc.)
.2RSNBR contact seal on both sides.
.2ZL
Lamellar seal on both sides.
A
Improved crowned profile of the outer ring running surface (NUTR design).
PPA
PA66 axial sliding and sealing ring on both sides. Improved crowned profile of the outer ring running surface.
PPXA
PA66 axial sliding and sealing ring on both sides. Cylindrical (flat) profile of the outer ring running surface.
X
Cylindrical (flat) profile of the outer ring running surface.


Suffixes - Cage design
TN
Glass fibre reinforced PA66 cage
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