Sugar Beet Harvester Product

Overview

The sugar beet harvester is a specialized machine designed for the unique requirements of beet extraction and cleaning. Sugar beets develop deep root systems (30–40 cm) requiring careful lifting to avoid damage that reduces processing yield and storage life. The machine integrates four discrete operations—topping, lifting, cleaning, and loading—into a continuous self-propelled platform optimized for maximum throughput and root quality.

Modern sugar beet harvesters employ a rotating cutting head to sever green foliage with precision, an underground share to lift roots with minimal breakage, a high-speed cleaning drum with air separation to remove adhering soil, and an onboard 5000 kg bunker to reduce transport cycles. Field capacities of 1.0–1.5 hectares per hour are typical for European sugar cooperatives managing 100–500 hectare blocks.

How it works

Topping Operation: A spinning disc (500 mm diameter, 8 radial hardened steel blades) rotates at 250 rpm directly above the beet crown. As the harvester moves forward at 4–8 km/h, the blades cut through foliage 20–50 mm above the root shoulder. Hydraulic cylinder control allows the operator to adjust cutting height from the cab, critical because topping too deep (>30 mm) removes valuable sugar-containing crown tissue, while topping too shallow (<15 mm) leaves excessive green matter that spoils storage. The precise cutting prevents beet head deformation and reduces cleaning difficulty downstream.

Root Extraction: Immediately following the topper, the Extraction Share undercuts soil 80 mm below the root crown. A depth wheel rolling on the soil surface maintains constant penetration depth as ground elevation varies. The lifting mechanism is spring-suspended on leaf tines that absorb shock when encountering rocks or hard pan, protecting the engine and operator from sudden impact. Spring suspension also prevents tugging and breaking of roots during extraction; the soil is merely undercut and loosened, allowing gravity and forward motion to slide the root from the ground.

Cleaning Turbine: Lifted beets, still encrusted with adhering soil, enter the Cleaning Drum—a perforated rotating cylinder (700 mm diameter, 300 rpm) with internal spiral vanes. As beets tumble inside, the vanes accelerate them against the perforated walls, dislodging compacted soil through 4 mm holes. A parallel centrifugal blower (6 kW) draws air through the drum, separating light soil particles from falling roots. The discharge screen (6 mm perforations) allows clean roots to pass while rejecting stones and large soil clods. Cleaning efficiency typically achieves 90–95% soil removal in a single pass, with <2% root bruising attributable to the cleaning drum.

Bunker and Discharge: Cleaned roots accumulate in the Root Tank—a 5000 L welded steel hopper positioned high above trailing vehicles. A helical discharge auger (200 mm pitch, 150 rpm) powered by a 20 cc/rev hydraulic motor conveys roots horizontally into trucks or trailers, achieving 4–5 tonnes per minute discharge. The onboard bunker eliminates the need for workers to hand-load and reduces turnaround time compared to pulled harvesters requiring a full harvest train.

Hydraulic Power: A 75 cc/rev variable-displacement axial piston pump (load-sensing, 210 bar rated) supplies pressurized fluid to four primary circuits: steering (rear axle via 70 mm bore cylinder), topping height adjustment (single-acting 50 mm cylinder), lift share depth (passively spring-suspended, no active control), and bunker auger discharge (20 cc/rev motor). Load-sensing compensation maintains modest stand-by pressure (20 bar) when no actuators demand flow, reducing thermal load during idling and improving fuel economy.

Electrical Architecture: An 80 A three-phase alternator supplies 24 V DC to the electrical bus. Four electric motors drive independently: topper head (7.5 kW, 1500 rpm, reduced to 250 rpm via 4:1 gearbox), cleaning drum (11 kW, 1500 rpm, reduced to 300 rpm), air cleaning fan (6 kW), and hopper conveyor motor (1.5 kW). Soft-start contactors ramp motor inrush current, protecting the alternator from transient voltage dips.

Chassis and Mobility: The self-propelled chassis uses 14.9/60-26 agricultural radial tires on dual axles. Front axle is driven through a 2.2:1 reduction gearbox and bevel differential (3.7:1), providing 1050 rpm at wheel hubs from the 2100 rpm engine. Rear axle is non-driven but hydraulically steered via a 70 mm bore cylinder, providing proportional turning control with a turning radius of 8 m. Leaf spring suspension (28 kN/m rate) with hydraulic dampers isolate the chassis from field impacts, crucial for protecting fine electrical control systems and ensuring operator comfort during long harvest days.

Root Quality Preservation: Sugar beet roots are metabolically active; damage during harvest triggers respiration and decay, reducing storage life and processing yield. The mechanical harvester is engineered to minimize breakage: the sharing undercut keeps the root intact even in heavy soil; the spring-mounted lift absorbs shock; the cleaning drum tumbles but does not crush; and the auger discharge slope is <30°, preventing roots from falling more than 1 m into trucks. Studies show mechanical harvesters achieve 95–98% root integrity, compared to 90–92% for hand digging.