Timken Part Numbering System
One of the most common questions we receive is in regards to the Timken number system and how to understand it. Hopefully with the information below will answer most questions you may have.
The ISO 355 international metric standard defines dimensions and cup angles for single-row tapered roller bearings. Originally intended to replace the ISO/R 355 standard, the new ISO 355 standard defined additional bearings and created new designation codes for the entire dimensional spectrum of ISO 355 metric bearings.
Because new designation codes would have incurred expense for many manufacturers and users, the market retained the designation codes for bearings that were in accordance with both the old and new standards.
*TIMKEN PART NUMBER PREFIXES AND SUFFIXES
Most Timken symbols are die stamped as part of the bearing number, however there are many cases where our automotive and industrial applications require special considerations in bearing designs and tolerances. To be certain future cone and cup replacements are made correctly, the factory supplements imprinted identifications with electric penciling to add prefixes and suffixes to the imprinted part numbers. These additional markings become important to the user for proper bearing identification and replacement.
Timken Part number system:
|
Prefix |
Suffix |
Definition |
|
. |
. |
EXAMPLE: CN-07237 |
|
. |
A |
CONE DIFFERENT BORE FROM STANDARD BASIC PART NUMBER. EXAMPLES: 495A VS 495 (NON-INTERCHANGEABLE) 567A VS 567 (NON-INTERCHANGEABLE) |
|
. |
A |
CONE DIFFERENT RADIUS FROM STANDARD BASIC PART NUMBER. EXAMPLES: 350A VS 350 (350 HAS LARGER RADIUS) 464A VS 464 (464 HAS LARGER RADIUS) |
|
. |
A |
CUP DIFFERENT O.D. FROM STANDARD BASIC PART NUMBER. EXAMPLE: 493A VS 493 (NON-INTERCHANGEABLE) |
|
. |
A |
CUP DIFERENT RADIUS FROM STANDARD BASIC PART NUMBER. EXAMPLE: 452A VS 452 (452A HAS LARGER RADIUS) |
|
. |
A |
CUP DIFFERENT LENGTH FROM STANDARD BASIC PART NUMBER. EXAMPLE: 394A VS 394 (NON-INTERCHANGEABLE) |
|
. |
AA |
CONE AND CUP DIFFERENT BORE OR O.D., OR LENGTH AND RADIUS FROM STANDARD BASIC PART NUMBER. EXAMPLE: 495AA VS 495A OR 495 |
|
. |
AB |
CUP FLANGED CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER). EXAMPLE: 572AB VS 572 |
|
. |
AC |
DIFFERENT CUP WIDTH OR RADIUS FROM BASIC PART NUMBER. |
|
. |
AC |
CUP DIFFERENT O.D. OR LENGTH AND RADIUS FROM STANDARD BASIC PART NUMBER). EXAMPLE: 453AC VS 453 (NON-INTERCHANGEABLE) |
|
. |
AD |
CUP DOUBLE CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER) . EXAMPLE: 592AD VS 592 (592 IS SINGLE CUP) |
|
. |
ADW |
DOUBLE CONE PILOTS AND SLOTS EACH END, HOLES IN LARGE RIB. |
|
. |
AH |
ASSEMBLED WITH SPECIAL CAGE, ROLLERS AND/OR INTERNAL GEOMETRY. |
|
. |
AS |
DIFFERENT BORE, OD, WIDTH OR RADIUS FROM BASIC PART NUMBER. |
|
. |
AS |
CONE AND CUP DIFFERENT BORE OR O.D. OR LENGTH AND RADIUS FROM STANDARD BASIC PART NUMBER. EXAMPLES: 372AS VS 372 (NON-INTERCHANGEABLE) 385AS VS 385 (NON-INTERCHANGEABLE) |
|
. |
AV |
MADE OF SPECIAL STEEL. |
|
. |
AW |
KEYWAY OR SLOTTED CONE RACE OR OUTER RACE. |
|
. |
AW |
CONE AND CUP KEYWAY OR SLOTTED CONE OR CUP. EXAMPLE: 389AW VS 389A (NON-INTERCHANGEABLE) |
|
. |
AX |
DIFFERENT BORE, OD, WIDTH, OR RADIUS FROM BASIC PART NUMBER. |
|
. |
AX |
CONE AND CUP DIFFERENT BORE OR O.D. OR LENGTH AND RADIUS FROM STANDARD BASIC PART NUMBER. EXAMPLES: 453AX VS 453 (NON-INTERCHANGEABLE) 495AX VS 495 (NON-INTERCHANGEABLE) |
|
. |
AXD |
ISO OUTER RACE - DOUBLE OUTER RACE WITHOUT OIL HOLES OR GROOVE. |
|
. |
B |
CUP FLANGED CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER) EXAMPLE: 572B VS 572 |
|
. |
B |
CONE USING BRASS CAGE. |
|
. |
BS |
CUP FLANGED CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER). EXAMPLE: 332BS VS 332 |
|
. |
BW |
CUP FLANGED CUP WITH SLOT (NON-INTERCHANGABLE WITH STANDARD BASIC PART NUMBER). EXAMPLE: 432BW VS 432 |
|
. |
C |
CUP DIMENSIONALLY DIFFERENT FROM BASIC PART NUMBER (NON-INTERCHANGEABLE). |
|
. |
C |
SINGLE CONE RACE, ENVELOPE DIMENSION SAME AS BASIC PART NUMBER. |
|
. |
CA |
DIFFERENT INTERNAL GEOMETRY. |
|
. |
CD |
DOUBLE CUP WITH OIL HOLES AND GROOVE. ONE HOLE COUNTER-BORED FOR LOCKING PIN. |
|
. |
CP |
CONE AND CUP FLASH CHROME PLATED. OTHERWISE, INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER. EXAMPLES: 18200CP (SUFFIX ELECTRIC PENCIL ETCHED) 18337CP (SUFFIX ELECTRIC PENCIL ETCHED) |
|
. |
CR |
CONE AND CUP RIB CUP BEARING SERIES. |
|
. |
CX |
DIMENSIONALLY DIFFERENT FROM BASIC PART NUMBER (NON-INTERCHANGEABLE). |
|
. |
D |
CONE AND CUP DOUBLE CONE OR DOUBLE CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER). EXAMPLES: 581D VS 581 (581 IS SINGLE CONE) 572D VS 572 (572 IS SINGLE CONE) |
|
. |
DA |
CONE DOUBLE CONE (NON-INTERCHANGEABLE WITH CONES HAVING SAME BASIC PART NUMBER) . EXAMPLE: 378DA VS 378DE |
|
. |
DA |
CUP SPHERICAL O.D. DOUBLE CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER OR OTHER DOUBLE CUPS HAVING SAME BASIC NUMBERS). EXAMPLES: 472D VS 472DD |
|
. |
DB |
CUP DOUBLE CUP WITH FLANGE (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER OR OTHER DOUBLE CUPS HAVING SAME BASIC NUMBERS). EXAMPLE: 09195DB VS 09195 |
|
. |
DC |
CUP DOUBLE CUP WITH HOLE FOR LOCKING PIN. |
|
. |
DD |
CONE AND CUP SPECIAL LONG DOUBLE CONE OR CUP (NON-INTERCHANGEABLE WITH STANDARD BASIC PART NUMBER OR OTHER DOUBLE PARTS HAVING SAME BASIC NUMBERS). EXAMPLE: 563DD |
|
. |
DE |
DOUBLE CONE OR DOUBLE CUP HAVING DIFFERENT DIMENSIONS OR OTHER CHARACTERISTICS FROM SINGLE AND DOUBLE PARTS IDENTIFIED WITH THE SAME BASIC PART NUMBER. |
|
. |
DGW |
CONE DOUBLE CONE WITH PRESSURE REMOVAL GROOVE IN BORE, AND HAVING FACE SLOTS. |
|
. |
DH |
DOUBLE CONE RACE WITH SPECIAL CAGE, ROLLERS AND/OR INTERNAL GEOMETRY. |
|
. |
DP |
CONE DOUBLE CONE WITH PULLER GROOVE. |
|
. |
DR |
CUP DOUBLE CUP FOR RIB CUP SERIES (NON-INTERCHANGEABLE WITH SINGLE AND DOUBLE CUPS IDENTIFIED WITH SAME BASIC NUMBER). |
|
. |
DS |
CUP CROWNED O.D. DOUBLE CUP (NON-INTERCHANGEABLE WITH OTHER CUPS HAVING SAME BASIC PART NUMBERS). EXAMPLE: 95927DS VS 95927D |
|
. |
DT |
CUP TAPERED O.D. DOUBLE CUP (NON-INTERCHANGEABLE WITH OTHER CUPS HAVING SAME BASIC PART NUMBERS). EXAMPLE: 473DT |
|
. |
DV |
DOUBLE CONE OR DOUBLE CUP RACE MADE OF SPECIAL STEEL. |
|
. |
DW |
CONE AND CUP DOUBLE CONE OR DOUBLE CUP WITH KEYWAY OR SLOT (NON-INTERCHANGEABLE WITH CONES OR CUPS IDENTIFIED WITH SAME 'BASIC PART NUMBERS). EXAMPLES: 378DW VS 378DA 128170DW VS 128170DA |
|
. |
DX |
CUP ADAPTOR FOR SPHERICAL OR STRAIGHT O.D. CUP. EXAMPLE: 128196DX (ADAPTOR FOR 128170DA CUP) |
|
. |
DX |
CUP THREADED O.D. DOUBLE CUP (NON-INTERCHANGEABLE WITH CUPS IDENTIFIED WITH SAME BASIC PART NUMBERS). |
|
. |
E |
CONE AND CUP CONES OR CUPS HAVING SPECIAL CHARACTERISTICS DIFFERING FROM AND NON-INTERCHANGEABLE WITH OTHER CONES OR CUPS IDENTIFIED WITH THE SAME BASIC PART NUMBERS. EXAMPLES: 6E (EXTRA LARGE O.D.) 742E (ROTARY GROUND FRONT FACE) |
|
. |
ED |
CUP DOUBLE CUP (NON- INTERCHANGEABLE WITH OTHER CUPS IDENTIFIED WITH SAME BASIC PART NUMBERS) . EXAMPLE: 384ED VS 384AD |
|
. |
F |
CONE ASSEMBLED WITH POLYMER CAGE. |
|
. |
G |
CONE RETAINER GROOVE IN BORE. |
|
. |
H |
CONE ASSEMBLED WITH SPECIAL CAGE, ROLLERS AND/OR INTERNAL GEOMERY. |
|
. |
HR |
SPECIAL CUP USED ON 'HYDRA-RIB' BEARING. |
|
. |
K |
CONE AND CUP FACTORY IDENTIFICATION ONLY. NOT PART OF NUMBER AND UNRELATED TO PHYSICAL DIMENSIONS. (INTERCHANGEABLE WITH OTHER CONES AND CUPS HAVING SAME BASIC PART NUMBERS). |
|
. |
L |
CONE ASSEMBLED WITH DUO-FACED SEALS. |
|
. |
MM |
CONE AND CUP FACTORY IDENTIFICATION ONLY. NOT PART OF NUMBER AND UNRELATED TO PHYSICAL DIMENSIONS (INTERCHANGEABLE WITH OTHER CONES AND CUPS HAVING SAME BASIC PART NUMBERS). |
|
. |
NA |
CUP SUFFIX ELECTRIC PENCIL ETCHED ON DOUBLE CUPS MATED WITH TWO "NA" TYPE SINGLE CONES TO FORM DOUBLE ROW NON-ADJUSTABLE BEARINGS. |
|
. |
NC |
CUP CUSHIONED CUP (USUALLY NEOPRENE). |
|
. |
NR |
CONE "NA" TYPE RIBLESS CONE FOR RIB CUP SERIES. |
|
. |
NW |
CONE "NA" TYPE CONE WITH SLOTTED FRONT FACE. |
|
. |
NX |
CONE LAPPED FRONT FACE |
|
. |
P |
CONE PULLER GROOVE. |
|
. |
R |
CONE AND CUP BOCK TYPE BEARING. EXAMPLES: 6358-R AND 6552-R |
|
. |
RB |
CUP SNAP RING ON O.D. EXAMPLES: 3822-RB, 15523-RB |
|
. |
S |
CONE AND CUP SPECIAL FEATURE BEARING. NOT INTERCHANGEABLE WITH BEARINGS HAVING SAME BASIC PART NUMBERS. |
|
. |
SA |
CONE AND CUP SPECIAL FEATURE BEARING. NOT INTERCHANGEABLE WITH BEARINGS HAVING SAME BASIC PART NUMBERS. |
|
. |
SB |
CONE WITH BRASS CAGE. |
|
. |
SB |
CUP FLANGED CUP. |
|
. |
SC |
CONE WITH SQUARE BORE. |
|
. |
SD |
CONE AND CUP DOUBLE CONE WITH SQUARE BORE OR DOUBLE CUP. |
|
. |
SH |
SPECIAL FEATURE BERING, WITH SPECIAL CAGE, ROLLERS AND/OR INTERNAL GEOMETRY (NON-INTERCHANGEABLE WITH BEARINGS HAVING SAME BASIC PART NUMBERS). |
|
. |
SW |
CONE AND CUP SLOT OR KEYWAY. NOT INTERCHANGEABLE WITH BEARINGS HAVING SAME BASIC PART NUMBERS. |
|
. |
T |
CONE TAPERED BORE. |
|
. |
T |
CUP TAPERED O.D. |
|
. |
TA |
CONE TAPERED BORE "NA" TYPE CONE. |
|
. |
TA |
CUP TAPERED O.D. |
|
. |
TB |
CONE TAPERED BORE CONE WITH BRASS CAGE. |
|
. |
TD |
CONE TAPERED BORE DOUBLE CONE. |
|
. |
TDE |
DOUBLE CONE WITH TAPERED BORE AND EXTENDED RIB. |
|
. |
TDH |
DOUBLE CONE WITH TAPERED BORE, SPECIAL CAGE, ROLLERS, OR INTERNAL GEOMETRY. |
|
. |
TDL |
CONE TAPERED BORE, DOUBLE CONE, WITH INTERLOCK FEATURE. |
|
. |
TDV |
DOUBLE CONE WITH TAPERED BORE. MADE OF SPECIAL STEEL. |
|
. |
TE |
CONE TAPERED BORE CONE WITH EXTENDED RIB. |
|
. |
TEV |
SINGLE CONE, TAPERED BORE, EXTENDED LARGE RIB. MADE OF SPECIAL STEEL. |
|
. |
TL |
CONE TAPERED BORE WITH INTERLOCK FEATURE. |
|
. |
TLE |
CONE TAPERED BORE WITH INTERLOCK FEATURE AND EXTENDED WIDTH. |
|
. |
TP |
CONE TAPERED BORE CONE WITH PULLER GROOVE. |
|
. |
TW |
CONE AND CUP TAPERED CONE BORE OR CUP O.D. WITH SLOTS OR KEYS. |
|
. |
U |
CONE OR CUP - BASIC SERIES PART NUMBER, UNITIZED, |