To answer this question, let's do a quick refresher on the ANSI part numbering system. The first digit(s) in each standard roller chain part number tells us the pitch of a chain in eighths of an inch. That means that an ANSI 120 chain, for example, has a pitch of 12/8s of an inch or 1.5 inches.
Let's say then that we wanted to know how many feet of chain are in an application of ANSI 120 that is 180 pitches in length?
Again, we know that ANSI 120 chain has a pitch of 1.5". For an application with 180 pitch, we simply multiply 1.5 inches by 180 to get 270 inches or convert to feet 270/12 = 22.5.
But what if we want to convert from feet into pitch? Let's say we have an application that uses 10 feet of ANSI 40 chain. We know that from the ANSI numbering system, ANSI 40 chain has a pitch of 4/8s of an inch or .5 inches. For an application of ten feet, we do a quick conversion from feet into inches (10 x 12 = 120) and then divide 120/.5 to get 240 pitches.
Knowing how to convert between pitch and feet can be useful, especially when double checking an order, but don't worry if you need additional help. The customer service team at Roller Chain Supply and application engineering teams are available to assist you. You can contact both groups by calling us at 1-844-732-0394.
For more information on how to measure your roller chain, download our PDF below.How to Properly Measure and Identify Roller Chain