Leaf chain part numbers are not arbitrary. The different combinations of letters and numbers represent the type of chain and describe the pitch as well as the chain lacing. With practice, these dimensions can be gleaned from the part number instantly.
The initial two letters in the leaf chain part number refer to the leaf chain series - for example, AL, EL-LL and BL-LH series leaf chains.
- AL series (American Light) chain, manufactured to the ANSI B29.9 standard, is constructed from American standard roller chain components. AL series chain is lightweight chain used for light load lifting applications and machine tools.
- EL-LL series (European Light – Leaf Light) chain, manufactured according to ISO4347, DIN8152 and NFE26107, is also constructed from roller chain components but to European standard. Like AL series chain, EL-LL series chain is a lightweight chain used for light load lifting applications and machine tools.
- BL-LH series (Leaf Heavy) chain, manufactured according to ISO4347, DIN8152, ANSI B29.8 and NFE26107, is the only leaf chain that is constructed from specific leaf chain components. BL-LH series leaf chain is heavier duty chain than ALand EL-LL series and so is the most common chain used for forklift trucks, lifting and materials handling equipment.
The first one or two digits (depending on whether the part number has three of four digits) refer to the pitch of the chain and vary according to the series.
- AL series chain is measured in 8ths of an inch - but only the numerator of the fraction is given. For example, 4 represents 4/8” which can be reduced to ½” and 10 represents 10/8” which can be reduced to 1 ¼”.
- EL-LL and BL-LL series chain is measured in both 8ths and 16ths of an inch. For example, BL12 represents 12/8” and LL24 represents 24/16” which can both be reduced to 1 ½”.
- The metric pitch can then be found by dividing the numerator by the denominator and multiplying by 25.4 as 1 inch is equal to 25.4 mm.