Spherical Roller Bearings · ISO 15 / GB/T 288 / DIN 635-2
ISO 15 21300 Series Spherical Roller Bearings Specification
What ISO 15 fixes, what it deliberately leaves to another document, its equivalents, and the dimensional table.
ISO 15 fixes the boundary dimensions of metric radial rolling bearings: the bore d, the outside diameter D, the width B and the limiting corner radius r, arranged in diameter and width series so that a bore of 20 mm exists in several standard envelopes (6004, 6204, 6304, 6404). It is the reason a 6204 from any manufacturer drops into the same housing.
Standard
ISO 15
Covers
Boundary dimensions of radial rolling bearings
Does not fix
It says nothing about how much load the bearing carries, how fast it may run, how accurately it is made or how much clearance it has. Load ratings are calculated to ISO 281, running accuracy is ISO 492 and radial internal clearance is ISO 5753-1.
Equivalents
DIN 616 restates the dimension plan nationally, with the individual bearing types in DIN 625, DIN 628, DIN 630, DIN 635 and DIN 5412; GB/T 273.3 carries the same plan in China.
Product
21300 Series Spherical Roller Bearings
Governing standards
ISO 15 / GB/T 288 / DIN 635-2
Equivalence between the ISO, DIN and GB/T documents is dimensional: a bearing made to either mounts in the same seat. It is not an equivalence of load rating, tolerance class or internal clearance, each of which is fixed by a separate standard and declared separately.
ISO 15 covers boundary dimensions of radial rolling bearings. This page sets out what the standard fixes for 21300 series spherical roller bearings, what it deliberately leaves to other documents, its national equivalents, and the dimensional table supplied against it.
ISO 15 — Scope
ISO 15 fixes the boundary dimensions of metric radial rolling bearings: the bore d, the outside diameter D, the width B and the limiting corner radius r, arranged in diameter and width series so that a bore of 20 mm exists in several standard envelopes (6004, 6204, 6304, 6404). It is the reason a 6204 from any manufacturer drops into the same housing.
What ISO 15 Does Not Fix
It says nothing about how much load the bearing carries, how fast it may run, how accurately it is made or how much clearance it has. Load ratings are calculated to ISO 281, running accuracy is ISO 492 and radial internal clearance is ISO 5753-1.
This division of labour is the thing to carry away from any bearing standard. A boundary dimension standard makes bearings interchangeable; it does not make them equivalent. Two bearings of the same designation from different makers mount in the same seat and are not required to have the same load rating, the same internal design, the same cage or the same speed limit.
Dimensions Supplied to ISO 15
Designation
Bore d (mm)
Outer diameter D (mm)
Width B (mm)
Chamfer r min (mm)
Permissible misalignment (deg)
21304
20
52
15
1.1
1
21305
25
62
17
1.1
1
21306
30
72
19
1.1
1
21307
35
80
21
1.5
1
21308
40
90
23
1.5
1
21309
45
100
25
1.5
1
21310
50
110
27
2
1
21311
55
120
29
2
1
21312
60
130
31
2.1
1
21313
65
140
33
2.1
1
21314
70
150
35
2.1
1
21315
75
160
37
2.1
1
21316
80
170
39
2.1
1
21317
85
180
41
3
1
21318
90
190
43
3
1
21319
95
200
45
3
1
21320
100
215
47
3
1
National Equivalents
DIN 616 restates the dimension plan nationally, with the individual bearing types in DIN 625, DIN 628, DIN 630, DIN 635 and DIN 5412; GB/T 273.3 carries the same plan in China.
This product is supplied against ISO 15 / GB/T 288 / DIN 635-2, which names the documents it is made to.
Catalog Products Governed by ISO 15
ISO 15 governs more than this one series. In this catalog it applies to:
Customize the parameters below — every spec field is editable, and the drawing redraws to match the values you choose. Changing the designation snaps the other fields to that size's standard values; you can then override any individual value.
Sends the selected values to the quote form below.
Our facility
The numbers come off our own machines
Every ring is gauged for bore and outside diameter, every assembly for radial internal clearance to ISO 5753-1, and every finished bearing for vibration. That is why the values on this page are quotable rather than indicative.
Request a Quote
The form below follows the current technical drawing configuration. Change the drawing values above and the request details update automatically.
Dimensions & Specifications (ISO 15 / GB/T 288 / DIN 635-2)
Designation
Bore d (mm)
Outer diameter D (mm)
Width B (mm)
Chamfer r min (mm)
Permissible misalignment (deg)
21304
20
52
15
1.1
1
21305
25
62
17
1.1
1
21306
30
72
19
1.1
1
21307
35
80
21
1.5
1
21308
40
90
23
1.5
1
21309
45
100
25
1.5
1
21310
50
110
27
2
1
21311
55
120
29
2
1
21312
60
130
31
2.1
1
21313
65
140
33
2.1
1
21314
70
150
35
2.1
1
21315
75
160
37
2.1
1
21316
80
170
39
2.1
1
21317
85
180
41
3
1
21318
90
190
43
3
1
21319
95
200
45
3
1
21320
100
215
47
3
1
Video: ISO 15 21300 Series Spherical Roller Bearings Specification
Third-party video, selected automatically for this topic. It is not produced by Bushing Bearings and is not a specification source — use the tables on this page for dimensional data.
Frequently Asked Questions
What does ISO 15 specify?
ISO 15 fixes the boundary dimensions of metric radial rolling bearings: the bore d, the outside diameter D, the width B and the limiting corner radius r, arranged in diameter and width series so that a bore of 20 mm exists in several standard envelopes (6004, 6204, 6304, 6404). It is the reason a 6204 from any manufacturer drops into the same housing.
What does ISO 15 not cover?
It says nothing about how much load the bearing carries, how fast it may run, how accurately it is made or how much clearance it has. Load ratings are calculated to ISO 281, running accuracy is ISO 492 and radial internal clearance is ISO 5753-1.
What is the equivalent of ISO 15?
DIN 616 restates the dimension plan nationally, with the individual bearing types in DIN 625, DIN 628, DIN 630, DIN 635 and DIN 5412; GB/T 273.3 carries the same plan in China.
Does ISO 15 mean two bearings are interchangeable?
Dimensionally, yes — that is what a boundary dimension standard is for, and a bearing of the same designation from any maker mounts in the same shaft and housing seat. Functionally, not necessarily: the load rating, the internal design, the cage, the clearance group and the speed limit are decided by the manufacturer and by other standards, and two bearings with the same number are not required to match on any of them.
How do I request a quotation?
Use the technical drawing on this page to pick the exact configuration, then submit it with the quote form. We respond within one business day.
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