ANSI roller chains

General information

Some of the roller chains used in Europe are designed according to the American ANSI B29.1 standard. This standard was originally used in the USA, but with the spread of various American machines, it began to be used all over the world. Based on their structure, roller chains consist of a pin, roller, connecting plate (sponge cake). The material and design of the parts determine the quality of the roller chains. However, the value specified in the standard is usually met by any roller chain. ANSI chains typically have a smaller inner width and narrower pin than ISO BS chains.

Thus, contrary to popular belief, ANSI chains are capable of a slightly smaller power transmission than their ISO BS counterparts. In everyday use, reinforced chains are usually not required. However, for lifting and other extreme load tasks, the ANSI standard introduced ANSI H (Heavy Duty) variants. With these products, the pin is hardened and thicker, the wall thickness of the sponge cake is ngayoer and the roller is made of better material.
When using chain drives, the tensile strength of the roller chains specified in the catalogue must always be taken into account!

How do I identify an ANSI (American) roller chain?

A power chain can generally be characterized by three parameters. The first is the pin spacing, which is also called simply division. This means the distance at which the links in the chain rotate over each other. This determines how large a sprocket can be used. The second important information is the roller diameter. This is the outer diameter of the cylinder pulled on the pin. This surface touches the arch formed at the base of the teeth of the sprocket. And the third important feature is the inner width. This is measured between the two links (sponge cakes) of the chain in the narrowest part. This size determines the width of the chain sprocket. Of course, in addition to the above dimensions, a thousand other things can be measured on a chain, and a thousand other things can be important for a specific application. However, knowing the division, roller diameter and inner width, it is already possible to identify a roller chain. In the product list, we provide the necessary dimensions for identification for each of our products. Additional information is available for products in the catalogues under the Downloadable Documents tab.

How are American (ANSI) roller chains designated?

In the original ANSI marking, the inch division of roller chains is indicated by numbers from 25 to 400. The ANSI number is the millimetre division value of the chain multiplied by 3.175. (For example, ANSI 40 = 12.7*3.175.)  However, ANSI chains also have ISO-based marking. (ISO markings explained in ISO chains.) In ISO marking, the letter A instead of the letter B after the two-digit number is used to denote ANSI roller chains. The marking ANSI 25 is equivalent to marking 04A. ANSI 35 stands for 06A. ANSI 40 is a replacement for 08A. ANSI 41 is a narrower version of the ANSI 40. There is no specific ISO trigger, but it is usually designated 082A. The ISO marking for chain ANSI 50 is 10A. The ISO marking for chain ANSI 60 is 12A. ANSI 80 can also be designated with the designation 16A. ANSI 100 corresponds to marking 20A. ANSI 120 is equivalent to marking 24A. The ANSI 140 was designated 28A. ANSI 160 corresponds to ISO marking 32A. The marking ANSI 200 is equal to the marking 40A. ANSI 240 is the same as 48A. If the number after the ANSI symbol ends in 5 instead of zero, it means a chain without a roller. (E.g. ANSI 40 instead of ANSI 45)

Are ANSI (ASA) roller chains stronger or weaker than ISO (BS) chains?

They are both stronger and weaker. The pin and side plate of standard ANSI chains are very slightly thinner than those of connecting ISO chains. Thus, we can say that normal ANSI chains are weaker than ISO roller chain pairs. However, the ANSI standard includes reinforced standard roller chains marked H (e.g. ANSI 50H). Reinforced ANSI roller chains have a stronger and hardened pin, as well as a stronger sponge cake. they are clearly more powerful than their standard ISO counterparts.