Page 284 - needle bearings

Needle rollers
NTN

Needle Rollers

NTN needle rollers are all made of high carbon chrome
bearing steel, fine-finished by grinding and polishing after Needle roller tolerances
heat-treated, and the hardness thereof ranges from Any needle rollers are manufactured with dimensional
HRC60 to 65. These needle rollers are supplied as not accuracy and profile accuracy conforming to JIS B 1506
only rolling element but also pin and shaft individuals. (Rollers for Roller Bearings). (Table 2)

Table 2 Needle roller tolerances Unit: Жm
End face profile of needle roller
Characteristics Tolerance and allowable value
F-type needle roller bearing with flat end face is
Tolerance for mean value of diameter Dw 0ʙʵ10
standard type, while A-type with round end face is semi-
standard type. In addition to these two types, another Mutual deviation of diameter Dw 2
needle roller type (nominal number with tail code E) Roundness of diameter Dw, 1.0 (Lw/Dwʽ6)
capable of damping edge load is also available. Feel free variation in diameter 1.5 (Lw/Dwʼ6)
to contact NTN for the detail thereof. Tolerance for length Lw h13
Accuracy class Class-2
Table 1 End face profile
Type Name Profile The needle rollers are delivered contained in same
package after the mutual deviation of diameter Dw was
F Flat
assorted to 2Жm and less. Before being delivered, the
A Round needle rollers are identified by label colors such as red,
dark blue, blue, etc. according to the respective
dimensional tolerances.
Further, mixed use of needle rollers contained in
packages of different label colors is prohibited.
Composition of nominal code
The nominal number comprises type code (end face
profile), dimension code [diameter (Dw)ʷlength (Lw)] and Table 3 Discrimination of needle rollers
tail code.
Label color Dimensional tolerance range Жm Discrimination
Red 0ʙʵ 2
Dark blue ʵ1ʙʵ 3
F 3ʷ17.8 E Blue ʵ2ʙʵ 4 Standard
Black ʵ3ʙʵ 5
White ʵ4ʙʵ 6
Tail code
Dimension code ɹE ɿwith crowning Gray ʵ5ʙʵ 7 Semi-
ɹAS ɿSpecial heat treatment Green ʵ6ʙʵ 8
Type code applied Brown ʵ7ʙʵ 9 standard
(See Table 1) ɹHL ɿSpecially surface-finished Yellow ʵ8ʙʵ10
1ʣ
ɹSF ɿFine surface-finished
ɹG ɿPolished end face

1) For HL refer to Subsection 11.1 “HL Bearings” on page A-52.
Fig. 1

B-222