American Standard Chains

American standard chains are covered by ISO 606, ANSI B29 .1 and DIN 8188 standards . The pitch sizes covered by this standard are 1/4 to 3 inch . American standard chains have a smaller pin diameter than the European standard equivalent . Wear resistance is therefore reduced when compared with the European standard chains . One exception is the 5/8 inch pitch, as in this case the pin and bushing diameters are larger than the European equivalent

American standard chains are normally referred to under the ANSI standard numbering system, for example a 1/2 inch pitch duplex (double strand) chain would be ANSI 40-2

The ANSI numbering system works as follows: The first number is the pitch size in 1/8 inch, i .e . 4/8 = 1/2 inch pitch . The second number refers to the chain being a roller chain, i .e . 0 = roller chain. A number 5 replacing the 0 would indicate a bushing chain and number 1 indicates a narrower series. The suffix, as with European standard chain, refers to the number of strands in the chain, that is in this case 2 = duplex (double strand) chain.