STANDARD REFERENCE / YZEFY SPROCKETS
ISO sprockets
ISO sprockets are used with short-pitch precision roller and bush chains specified within the ISO 606 system. The standard covers associated sprockets as well as chain dimensions, so it is a useful reference for international OEM machinery, industrial transmission, conveyors and cross-border replacement work. ISO 606 has A-series references derived from ANSI practice and B-series references used across European and related systems. Select the correct series first, then specify chain size, strand, teeth, bore, keyway and hub. For a custom or replacement sprocket, send the drawing, chain marking, sample or measured part.
Standard reference
ISO Sprockets
- SpecificationDetails
- Standard referenceISO 606:2015, short-pitch transmission precision roller and bush chains and associated sprockets
- Chain familiesA series and B series, with different dimensions even when pitch is shared
Quick Specifications
| Specification | Details |
|---|---|
| Standard reference | ISO 606:2015, short-pitch transmission precision roller and bush chains and associated sprockets |
| Chain families | A series and B series, with different dimensions even when pitch is shared |
| Common A-series references | 04A, 06A, 08A, 10A, 12A and 16A |
| Common B-series references | 04B, 05B, 06B, 08B, 10B, 12B, 16B, 20B and 24B |
| Strand | Simplex, duplex and triplex, identified by the complete chain suffix |
| Sprocket forms | Type A plate, Type B hub, Type C double hub and other drawing-defined forms |
| Bore options | Pilot bore, finished bore, keyed bore, bushing interface and custom shaft interface |
| Selection basis | ISO series, chain dimensions, teeth, strand spacing, bore, keyway and hub |
Available Sizes
ISO A-series and B-series use separate child-page records. B-series pages are shared with the DIN and BS parent pages.
A-series
B-series
Chain & Size Reference
The table separates A-series and B-series chain dimensions in millimetres. These values are for identifying the mating chain. They do not define pitch diameter, outside diameter, tooth width or bore for a finished sprocket.
| ISO 606 reference | Series | Pitch | Roller diameter | Inner width |
|---|---|---|---|---|
| 04A | A | 6.350 | 3.300 | 3.180 |
| 06A | A | 9.525 | 5.080 | 4.770 |
| 08A | A | 12.700 | 7.950 | 7.850 |
| 10A | A | 15.875 | 10.160 | 9.400 |
| 12A | A | 19.050 | 11.910 | 12.570 |
| 16A | A | 25.400 | 15.880 | 15.750 |
| 04B | B | 6.000 | 4.000 | 2.800 |
| 05B | B | 8.000 | 5.000 | 3.000 |
| 06B | B | 9.525 | 6.350 | 5.720 |
| 08B | B | 12.700 | 8.510 | 7.750 |
| 10B | B | 15.875 | 10.160 | 9.650 |
| 12B | B | 19.050 | 12.070 | 11.680 |
| 16B | B | 25.400 | 15.880 | 17.020 |
| 20B | B | 31.750 | 19.050 | 19.560 |
| 24B | B | 38.100 | 25.400 | 25.400 |
The A and B rows can share a pitch while differing in roller diameter or inner width. That difference changes the tooth gap and sprocket tooth width. A chain number without its series suffix is therefore incomplete.
Available Sprocket Configurations
Sprocket forms
- Type A plate sprockets for compact drives or separate-hub assemblies.
- Type B sprockets with a hub on one side.
- Type C sprockets with hubs on both sides or a wider shaft interface.
- Idler, split, weld-on, bushing-mounted and other forms defined by the machine drawing.
Strand configurations
Specify simplex, duplex or triplex. The sprocket must match the chain series and the transverse spacing between rows. An 08A sprocket and an 08B sprocket are not interchangeable merely because both have a 12.700 mm pitch.
Materials
Carbon steel is common for general industrial transmission. Alloy steel can be specified for higher load, shock or wear requirements. Stainless steel is considered for corrosion, washdown and cleaning exposure. Cast iron, aluminum and engineering plastics may fit specific low-load, weight-sensitive or corrosion-controlled applications.
State the material grade, supply condition and certificate requirement in the RFQ. Choose the material against load, speed, shock, lubrication, temperature, corrosion and cleaning conditions rather than the ISO series alone.
Heat Treatment & Surface Treatment
Tooth hardening and induction hardening can address repeated tooth wear. Carburizing can be specified when a hard case and tougher core are required. Protective surface treatment can be used for corrosion exposure, storage or washdown conditions.
If the drawing controls hardness, case depth, treated area, surface finish or inspection, include those values. If the old drawing does not state a treatment, provide the load cycle, speed, lubrication and environment for review with the material and tooth geometry.
Custom ISO Sprockets
Custom ISO sprockets start with the series suffix, not pitch alone. Send A or B series, complete chain reference, number of teeth, strand, bore, keyway, hub dimensions and quantity. Add material, treatment, tolerances, marking and inspection requirements from the drawing.
For a drawing-controlled OEM order, include the revision and mating chain reference. For a sample-based order, add photos, tooth count, pitch, roller diameter, inner width, face width and shaft measurements. The application speed, load and center distance help resolve missing design details.
Replacement Sprockets
ISO replacement sprockets are often requested for international equipment where the drawing uses an ISO, ANSI-derived A-series or European B-series designation. Provide the chain marking, series, tooth count, bore, keyway, hub and any part number. Include the original drawing or a measured sample whenever possible.
Do not substitute an A-series part for a B-series part without comparing dimensions. Inspect the chain for elongation and the old sprocket for tooth wear before deciding whether a matched chain and sprocket replacement is needed.
Applications
ISO sprocket requests commonly come from international OEM machinery, cross-border replacement programs, global industrial equipment, conveyors and procurement teams that need a common technical reference. The ISO page is also useful when a buyer is comparing an ANSI-derived A-series chain with a European B-series chain.
The ISO label narrows the standard family, but it does not select the part. Series, chain dimensions, teeth, strand spacing, bore and hub still determine the finished sprocket.
Standard & Compatibility Notes
ISO 606:2015 is the published fourth edition covering short-pitch transmission precision roller and bush chains, attachments and associated chain sprockets. It contains A-series and B-series references. A-series dimensions are derived from ANSI practice, while B-series dimensions represent the European family used in many DIN and BS references.
DIN ISO 606:2018-02 is the German adoption of ISO 606:2015. BS ISO 606:2015 is the UK implementation. JIS B 1801:2020 is based on ISO 606:2015 but is marked MOD, meaning that it contains technical modifications. These relationships support navigation between standards, not automatic interchangeability.
How to Select
- Identify ISO 606 and the A-series or B-series suffix.
- Record the complete chain number and simplex, duplex or triplex suffix.
- Verify pitch, roller diameter, inner width and transverse spacing.
- Record driver and driven teeth, speed ratio, center distance and chain line.
- Select Type A, Type B, Type C or another drawing-defined form.
- Specify bore, keyway, locking method, hub dimensions and axial clearance.
- Add material, treatment, finish, quantity and inspection requirements.
- Attach the drawing, sample or chain marking when the standard relationship is uncertain.
FAQ
What does ISO 606 cover?
ISO 606 covers short-pitch transmission precision roller and bush chains, attachments and associated chain sprockets. It includes A-series and B-series chain references with their dimensional requirements.
What is the difference between ISO A-series and B-series chains?
The A and B series can share a pitch while using different roller diameters, inner widths and transverse dimensions. Select the series suffix with the chain number rather than using pitch alone.
Are ISO and ANSI sprockets interchangeable?
An ISO A-series chain may correspond to an ANSI-derived reference, but a full comparison is still required. ISO B-series chains are a different family at many shared pitches.
How are DIN and BS related to ISO 606?
DIN ISO 606 and BS ISO 606 are national implementations of the ISO system. Legacy DIN or BS drawings still need their edition and dimensions checked before a current part is substituted.
How does JIS relate to ISO 606?
JIS B 1801:2020 is based on ISO 606:2015 and marked MOD. It should be treated as a related standard with technical modifications, not as an unqualified identical copy.
Can an ISO sprocket be made from a drawing or sample?
Yes. Send the ISO series, chain reference, teeth, bore, keyway, hub, material, treatment, quantity and drawing or sample details for a technical review.
Request a Quote for ISO Sprockets
Send the ISO series, complete chain reference, strand, number of teeth, bore, keyway, hub, quantity and application. Attach the drawing, sample photo, chain marking or measured existing sprocket for custom and replacement work. This prevents an A-series and B-series pitch match from being treated as a complete fit confirmation.