How Do I Measure Roller Chain?
With the multitude of applications for industrial roller chain, it is no surprise that it is available in many types, shapes, and sizes. Here at MDS of Michigan, we offer double pitch, double strand, single strand, stainless steel, and heavy roller chain.
First, let’s clarify what you are looking for. If you already know the chain size but are unsure of its dimensions, you can use a chain dimensions chart to confirm the measurements. If you have a chain on hand but are unsure of the size so that you can order more, you will need to measure the chain and compare those measurements to a roller chain size chart.
Most important measurement: Chain pitch is the first measurement you should check. Pitch is the distance from the center of one pin to the center of the next pin, and it is usually the fastest way to narrow down the correct roller chain size.
Read Our Standard Roller Chain Size Chart
Measuring Roller Chain
Before we begin, save yourself some trouble and take a good look at the chain. Oftentimes, you will find the size stamped on the side of the plate. You may have to clean off some dirt and grease to see it.
Not seeing it? Well, that would be too easy. You will have to measure the roller chain using a caliper and then locate those dimensions on a chart to find the size to order. You will be looking for the chain pitch, roller width, roller diameter, plate height, and plate thickness.
Chain Pitch
To find the chain pitch, measure the distance between the center of one pin and the center of the next pin. This is the most important measurement because roller chain size is largely based around pitch. For example, #40 roller chain has a 1/2″ pitch, #50 roller chain has a 5/8″ pitch, #60 roller chain has a 3/4″ pitch, and #80 roller chain has a 1″ pitch.
For larger chains, you may be able to measure pitch with a ruler or tape measure, but a caliper is always the better option. If the chain is worn or stretched, measure across several links and divide by the number of pitches to get a more accurate measurement.
Roller Width
The roller is the cylindrical component between the two inside plates of the chain link. Use the caliper to measure the inside width between the inner plates. This helps confirm the chain size after you have measured the pitch.
Roller Diameter
The roller diameter is the thickness of the roller itself. Slide the caliper against the rounded sides of the roller to determine the diameter. This is another important measurement when comparing your chain to a roller chain size chart.
Plate Height
Each roller chain link has plates on either side. These plates can either be straight, sometimes known as a straight sidebar, or curved, often referred to as a figure-8 sidebar. Lay the chain flat on a table so that the rollers are visible from the top. Looking at the chain from the side, measure from the top of the plate to the bottom to determine the height. For a figure-8 plate, measure at the tallest part surrounding the pin.
Plate Thickness
Keeping the chain flat with the rollers facing up, measure the width of the plate to find the plate thickness. This is where a caliper is very important, as thicknesses can range from 0.03″ to 0.218″ with plenty of outliers.
Quick tip: Start with pitch, then confirm with roller width, roller diameter, plate height, and plate thickness. Pitch gets you close, but the other dimensions help make sure you order the correct chain.
Now that you have your roller chain dimensions, simply find them on this roller chain size chart to locate your roller chain size and order online.
