Are 40 Roller Chain and 08B Roller Chain interchangeable?
When working with industrial roller chains, you may come across two commonly used sizes: #40 (ANSI) and 08B (ISO/British Standard). They share the same pitch — 1/2 inch (12.7 mm) — which often leads to the assumption that they are interchangeable. But are they really?
40 Roller Chain VS 08B Roller Chain Dimension
Chain Standard | ANSI B29.1 | ISO 606/ BS 228 |
| Chain Pitch | 12.7 mm | 12.7 mm |
| Chain Roller Diameter | 7.95 mm | 8.51 mm |
| Inner Width | 7.85 mm | 7.75 mm |
Plate Thickness | Thinner | Thickness |
Common Usage Region | USA, Asia | Europe, ISO regions |
Are #40 Chain and 08B Chain Interchangeable?
Even though 40 and 08B chains have the same pitch, their inner width and roller profile are not identical. 08B chain can not going to mesh 40 chain sprocket properly because of 08B chain and the 40 roller chain have different roller diameters.
So even if you can technically loop an 08B chain over a #40 sprocket, the result will be misalignment, abnormal wear, or mechanical failure.
Risks of Using the Wrong Chain
Trying to mix ANSI and ISO chains with mismatched sprockets can lead to:
▶ Excessive noise
▶ Faster chain wear or elongation
▶ Sprocket tooth damage
▶ Reduced efficiency
▶Unexpected breakdowns
How to Choose the Right Roller Chain
Match the chain to the sprocket standard – ANSI chains go with ANSI sprockets; Metric roller chains go with Metric chain sprockets.
Know your region's standard – Use ANSI in the US and ISO in Europe.
Double-check measurements – Especially inner width and roller diameter.
Consult your supplier – They can help verify compatibility for your application.
Need help selecting the right roller chain? Contact our expert team – we're here to help you get it right the first time.
CTS® | Professional Roller Chain Supplier
CTS®-ChinaTransmissionS is a professional roller chain supplier with over 14 years in the power transmission industry. Our experienced technical team always learns the latest manufacturing technology. We would be a better choice for you to build a long-term and stable cooperation with. We can provide priority service and a fast response the first time. In addition, we can also offer high-quality roller chains at a competitive price.
We offer a wide range of industrial chain options: roller chains, conveyor chains, stainless steel chains, heavy-duty roller chains, double-pitch roller chains, roller chain attachments, industrial chain sprockets, etc.
If you have any questions about roller chains, please contact us to help you.
