JB/T 5389.2-2017Rolling bearings - Roller bearings for rolling mills - Part 2: Double-row and four-row tapered roller bearings (English PDF)

1 Scope

This part of JB/T 5389 specifies the main identification codes, structural types, boundary dimensions, technical specifications, inspection methods, inspection rules and marking and rustproof packaging of double-row tapered roller bearings for rolling mills (hereinafter referred to as the “double-row bearing”) and the four-row tapered roller bearings for rolling mills (hereinafter referred to as the “four-row bearing”).

This part is applicable to the production, inspection and acceptance of double-row and four-row tapered roller bearings for rolling mills.

2 Normative References

The following referenced documents are indispensable for the application of this document. For dated reference, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 272 Rolling Bearing - Identification Code

GB/T 299-2008 Rolling Bearings - Metric Double Row Tapered Roller Bearings - Boundary Dimensions

GB/T 300-2008 Rolling Bearings - Four Row tapered Roller Bearings - Boundary Dimensions

GB/T 307.2-2005 Rolling Bearings - Measuring and Gauging Principles and Methods

GB/T 307.3-2005 Rolling Bearings - General Technical Regulations

GB/T 699-2015 Quality Carbon Structure Steel

GB/T 711-2008 Hot-rolled Quality Carbon Structural Steel Plates, Sheets and Wide Strips

GB/T 3203-2016 Specification for Carburizing Steels of Bearings

GB/T 4199-2003 Rolling Bearings - Tolerances - Definitions

GB/T 7811-2015 Rolling Bearings - Symbols for Physical Quantities

GB/T 8597-2013 Rolling Bearings - Rust Proof Packaging

GB/T 13237-2013 Cold Rolled Quality Carbon Structural Steel Sheets and Strips

GB/T 18254-2016 High-carbon Chromium Bearing Steel

GB/T 24605-2009 Rolling Bearings - Marking for Products

GB/T 24608-2009 Inspection Rules for Rolling Bearings and Commercial Parts

JB/T 1255-2014 Rolling Bearings - Parts Made from High-carbon Chromium Bearing Steels - Specifications for Heat Treatment

JB/T 7051-2006 Rolling Bearing Parts - Methods for the Measurement and Assessment of Surface Roughness

JB/T 8236-2010 Rolling Bearings - Internal Clearances and Adjusting Methods for Double-row and Four-row Tapered Roller Bearings

JB/T 8881-2011 Rolling Bearings - Carburizing Heat - Treatment for Parts - Specifications

JB/T 10336-2017 Rolling Bearings - Supplementary Specifications

3 Symbols

For the purposes of this document, the symbols given in GB/T 4199-2003 and GB/T 7811-2015 and the following apply.

D1mp max-D2mp min: the difference between the maximum and minimum mean outside diameters of the outer rings of a bearing.

d1mp max-d2mp min: the difference between the maximum and minimum mean bore diameters of the inner rings of a bearing.

r: the nominal chamfer of inner ring rsmin: the minimum single chamfer dimension of inner ring r1: the nominal chamfer of outer ring r1min: the minimum single chamfer dimension of outer ring

T3: the width of Type 370000 and Type 370000D double-row tapered roller bearings (assembly)

4 Identification Code

The identification code of bearings shall be in accordance with those specified in GB/T 272.

5 Main Structural Types (See Figures 1~4)

Figure 1 Double-row Tapered Roller Bearing

Type 350000 Figure 2 Double-row Tapered Roller Bearing

Type 370000

Figure 3 Double-row Tapered Roller Bearing

Type 370000D Figure 4 Four-row Tapered Roller Bearing

Type 380000

6 Boundary Dimensions