Agricultural Chains for Root Crop Harvester

The main power transmission chain driving the working components. Requires heavy-duty specification matched to the peak torque of the application.

Moves material through the machine. Must resist abrasion from crop material and environmental contamination while maintaining dimensional accuracy.

Sub-drives for auxiliary systems. Light to medium duty but must be dimensionally compatible with the primary drive timing where applicable.

Root crops in Australia are grown predominantly in light sandy soils — coastal dunes, river flats, and sandy loam profiles — that are high in silica particles. These particles are harder than chain steel and act as a continuous abrasive on pin surfaces, bushing bores, and roller contact zones. Digger web chains in sandy soil conditions typically wear 3–4 times faster than the same chain in heavy clay soils with lower silica content.

Potato and carrot harvest in irrigation-dependent growing regions such as the Riverina, Manjimup, and Atherton Tablelands occurs at soil moisture levels that sustain crop quality but are high enough to form a paste of soil and silica around chain joints. This paste accelerates abrasion by maintaining particle contact with pin and bushing surfaces through the full work cycle.

The digger web carries the full load of lifted soil — typically 20–35 tonnes per hour of soil-crop-stone mix — in continuous rotation throughout the harvest day. Any stone that passes through the web and enters the sprocket zone creates impact loads that damage rollers and cause connected link failure if chain specification does not account for this event.

Wash down web chains and sprockets with fresh water to remove soil paste from roller and pin surfaces. Apply lubricant to all chain joints while the chain is still warm from operation — warm chains accept lubricant penetration more effectively than cold chains. Inspect for stiff or seized rollers.

Measure web chain elongation across a 12-link span. Replace at 2.0% elongation for primary web, 1.5% for elevator chains. Inspect all sprocket tooth surfaces for abrasive grooving — replace any sprocket with visible groove wear extending more than 1 mm into the tooth face.

Full chain removal and inspection. Measure roller diameter for evidence of abrasive thinning. Chains showing measurable roller diameter reduction (more than 5% of original) should be replaced regardless of elongation measurement, as thin rollers concentrate load on sprocket tooth tips.