What Is a CA550 or CA620 Agricultural Roller Chain and Where Is It Used

CA550 and CA620 agricultural roller chain are the most widely used chain specifications in grain harvesting and agricultural conveyor equipment throughout Australia. Unlike standard ANSI roller chain, CA-type agricultural chain is specifically designed for the wide-pitch, high-load conveying and feeding applications found in combine harvesters, grain elevators, forage harvesters, and bagger systems.

CA550 and CA620 agricultural roller chain comparison showing straight sidebar inner plates versus standard ANSI waisted plates

What Makes CA-Type Chain Different From Standard ANSI Chain

CA-type agricultural roller chain differs from standard ANSI chain in the inner link plate design. Standard ANSI inner link plates are waisted — narrowed between the pin holes for weight reduction. CA-type inner link plates are straight-sided — the same rectangular width across their full length. This straight sidebar provides a wider, flat surface on each inner link suitable for direct use as a conveyor carrying surface and for mounting attachment plates.

Specification	CA550	CA620	Standard ANSI 120 (same pitch as CA550)
Pitch	38.10 mm	41.28 mm	38.10 mm
Inner Link Width	25.65 mm	25.40 mm	25.22 mm
Plate Style	Straight sidebar	Straight sidebar	Waisted (narrowed)
Primary Applications	Grain elevators, feeder house, small elevators	Corn gathering, forage harvester, silage baggers	General industrial power transmission
Sprocket Series Required	55-series	62-series	Standard ANSI 120 sprocket

Where CA550 Chain Is Used in Australian Agricultural Equipment

CA550 agricultural roller chain is found in the conveying and feeding systems of grain harvesting and handling equipment across Australia: grain elevator legs in on-farm storage silos; combine harvester straw elevator systems; seed cleaner and grain grader conveying chains; portable auger and bucket elevator chain drives where the straight sidebar allows product to be carried directly on the inner plate surface. The straight sidebar inner plate allows slats, paddles, or flight attachments to be bolted directly to the inner plate — a key advantage over standard ANSI chain.

Where CA620 Chain Is Used

CA620 agricultural roller chain is found in more demanding applications than CA550 — specifically corn gathering heads, forage harvesters, silage baggers, and manure spreaders. CA620 has a slightly larger pitch (41.28 mm versus 38.10 mm for CA550) and higher breaking load, making it appropriate for gathering and feeding systems that handle bulkier or heavier crop materials.

Identifying the Correct Sprocket for CA-Type Chain

The most common maintenance error with CA-type agricultural chain is using the wrong sprocket series. CA550 chain requires 55-series sprockets; CA620 chain requires 62-series sprockets. Using a standard ANSI 120 sprocket with CA550 chain — even though the pitches match — is not correct. The tooth profile and chain engagement geometry differ between the ANSI standard and the CA agricultural chain standard, and using the wrong sprocket causes accelerated wear and potential disengagement.

CA550 CA620 sprocket series identification showing 55-series and 62-series sprocket profiles and chain compatibility

EverPower Roller Chains Australia supplies CA550 and CA620 agricultural roller chain with matching 55-series and 62-series sprockets. Contact +61 2 9708 3322 or [email protected].

+61 2 9708 3322 | [email protected] | 27 Harley Crescent, Condell Park NSW 2201

Frequently Asked Questions

Can I use standard ANSI 120 chain instead of CA550 chain? +

Standard ANSI 120 chain has the same 38.10 mm pitch as CA550, but the waisted inner plate does not provide the flat mounting surface that CA550 straight sidebar inner plates provide. If attachment plates or direct product carrying on the inner plate is required, ANSI 120 chain is not an appropriate substitute.

What is the difference between CA550 and CA550HD? +

CA550HD (Heavy Duty) has thicker link plates and higher minimum tensile strength. It is specified for the primary drives of high-capacity grain elevators and combine harvester main feeder chains under heavy crop conditions.

How do I know if my existing chain is CA550 or CA620? +

Measure the chain pitch: CA550 = 38.10 mm; CA620 = 41.28 mm. Also observe the inner plate shape — CA-type chain has a straight rectangular inner plate profile (no waisting), which visually distinguishes it from standard ANSI chain at the same pitch.

Can I mix CA550 and CA620 chain in the same loop? +

No — different pitches (38.10 mm versus 41.28 mm) make them physically impossible to mix in the same loop. Always use the same chain type and pitch throughout a complete chain loop.

Where can I buy CA550 and CA620 chain in Australia? +

EverPower Roller Chains Australia maintains stock of CA550 and CA620 chain with matching 55-series and 62-series sprockets at our Sydney facility. Contact +61 2 9708 3322 for same-week despatch on stocked sizes.