How to Measure Double Strand Roller Chain
Most important measurement: Start with chain pitch. Pitch is the distance from the center of one pin to the center of the next pin. This is usually the fastest way to narrow down the correct double strand roller chain size.
Read Our Standard Roller Chain Size Chart
What Is Double Strand Roller Chain?
Double strand roller chain is roller chain with two parallel rows of chain connected together. It uses the same basic measurements as standard roller chain, but it has more load capacity than a single strand chain of the same size because the load is spread across two strands.
Do not confuse double strand roller chain with double pitch roller chain. Double strand means two rows of chain side by side. Double pitch means the distance between pins is longer than standard roller chain. If you are ordering replacement chain, it is important to know which one you have.
Look for the Chain Size First
Before grabbing a caliper, take a close look at the chain. Many roller chains have the chain size stamped on the side plate. You may need to wipe away dirt, grease, or oil to see it clearly.
If the chain is marked, you may see a number such as 40-2, 50-2, 60-2, or 80-2. The first number identifies the chain size, and the “-2” usually means double strand. If the stamp is missing or unreadable, you will need to measure the chain.
How to Measure Double Strand Roller Chain
To identify double strand roller chain, use a caliper and check the measurements below. Start with pitch, then confirm the chain has two rows of rollers side by side. After that, compare the roller width, roller diameter, plate height, and plate thickness to the double strand roller chain size chart.
Step 1
Measure Chain Pitch
Measure from the center of one pin to the center of the next pin. Pitch is the most important measurement because roller chain size is largely based around pitch. For example, #40 chain has a 1/2″ pitch, #50 chain has a 5/8″ pitch, #60 chain has a 3/4″ pitch, and #80 chain has a 1″ pitch.
Step 2
Confirm It Is Double Strand
Look at the chain from the top. Double strand roller chain has two rows of rollers running side by side. Many double strand chains are also marked with “-2” after the chain size, such as 40-2, 50-2, 60-2, or 80-2.
Step 3
Measure Roller Width
The roller is the cylindrical part between the inside plates. Use a caliper to measure the inside width between the inner plates on one strand of the chain. This helps confirm the chain size after you measure pitch.
Step 4
Measure Roller Diameter
Roller diameter is the thickness of the roller itself. Place the caliper against the rounded sides of the roller to determine the diameter. This measurement is important when comparing your chain to a size chart.
Step 5
Measure Plate Height
Lay the chain flat and look at the chain from the side. Measure from the top of the plate to the bottom of the plate. If the side plate has a figure-8 shape, measure at the tallest point around the pin.
Step 6
Measure Plate Thickness
Plate thickness is the thickness of one side plate. Use a caliper because small differences matter. This measurement can help confirm the chain size and identify heavy-duty chain variations.
Quick tip: Start with pitch, then confirm roller width, roller diameter, plate height, and plate thickness. Pitch gets you close, but the other dimensions help make sure you order the correct double strand roller chain.
Double Strand Roller Chain Dimensions
Use the chart below to compare common double strand roller chain sizes. Click the chain size to shop available double strand roller chain from MDS of Michigan.
| #35 Double Strand Pitch: 3/8″ Roller Width: 0.188″ Roller Diameter: 0.200″ Plate Height: 0.34″ Plate Thickness: 0.05″ |
| #40 Double Strand Pitch: 1/2″ Roller Width: 0.312″ Roller Diameter: 0.312″ Plate Height: 0.463″ Plate Thickness: 0.06″ |
| #50 Double Strand Pitch: 5/8″ Roller Width: 0.375″ Roller Diameter: 0.40″ Plate Height: 0.579″ Plate Thickness: 0.08″ |
| #60 Double Strand Pitch: 3/4″ Roller Width: 0.500″ Roller Diameter: 0.469″ Plate Height: 0.579″ Plate Thickness: 0.094″ |
| #80 Double Strand Pitch: 1″ Roller Width: 0.625″ Roller Diameter: 0.625″ Plate Height: 0.935″ Plate Thickness: 0.125″ |
| #100 Double Strand Pitch: 1-1/4″ Roller Width: 0.75″ Roller Diameter: 0.75″ Plate Height: 1.165″ Plate Thickness: 0.156″ |
Once you have measured your chain, compare your dimensions to the chart above. If the measurements line up, you can click the chain size to shop double strand roller chain online from MDS of Michigan.
Shop Double Strand Roller Chain
Still not sure what chain you have? Send MDS of Michigan a photo of the chain, the pitch measurement, roller width, roller diameter, and any markings stamped on the side plates. Our team can help identify the chain and point you toward the correct replacement.
