Standard No.:	GB/T 300-2008
English Name:	Rolling bearings—Four row tapered roller bearings—Boundary dimensions
Chinese Name:	滚动轴承 四列圆锥滚子轴承 外形尺寸
Chinese Classification:	J11    Rolling bearing
Professional Classification:	GB    National Standard
ICS Classification:	21.100.20 21.100.20    Rolling bearings 21.100.20
Source Content Issued by:	AQSIQ; SAC
Issued on:	2008-2-28
Implemented on:	2008-8-1
Status:	superseded
Superseded by:	GB/T 300-2023 Rolling bearings—Four-row tapered roller bearings—Boundary dimensions
Superseded on:	2023-12-1
Superseding:	GB/T 300-1995 Rolling bearings―Four row tapered roller bearings―Boundary dimensions
Target Language:	English
File Format:	PDF
Word Count:	2000 words
Translation Price(USD):	40.0
Delivery:	via email in 1 business day

1 Scope This standard specifies the boundary dimensions of four row tapered roller bearings. This standard is applicable to four row tapered roller bearings and is used for the bearing manufacturer's design and the customer's type selection. 2 Symbols (See Figure 1) For the purpose of this standard, the following symbols apply. Unless otherwise stated, all the symbols shown in figures and the values shown in tables denote the nominal dimensions. B: Total width of bearing inner ring B1: Width of inner ring with double raceways b: Width of outer ring spacer C: Total width of bearing outer ring D: Bearing outside diameter d: Bearing bore diameter r1: Front face chamfer dimension of inner ring r1smin: Smallest single front face chamfer dimension of inner ring r2: Back face chamfer dimension of outer ring r2smin: Smallest single back face chamfer dimension of outer ring

Foreword I 1 Scope 2 Symbols (See Figure 1) 3 Boundary Dimensions 4 Marking Example