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Tong Engineering, a market leader in the design and manufacture of vegetable grading, handling and cleaning machinery, is using precision motion components supplied by R.A. Rodriguez (U.K.) Limited in its latest innovation, the FieldLoad PRO. A KDM-series turntable bearing and pinion provide each machine with an effective and reliable solution for the crop unloading elevator, ultimately helping the company to meet customer demand for ever-greater efficiency and quality in this highly competitive arena.

With roots dating back to 1930 as a humble ironmonger in the market town of Spilsby, Lincolnshire, Tong Engineering has evolved into a £19 million turnover business that specialises in manufacturing advanced vegetable handling equipment – from single machines to complete, custom-built solutions. The company exports its world-class equipment to more than 50 countries, providing machinery for processing everything from potatoes, onions and carrots, to parsnips, Brussels sprouts, swedes and more.

Constant innovation is one of the principal keys to retaining Tong’s market-leading position. The next-generation FieldLoad PRO is a case in point. Offering effective and versatile in-field and on-farm crop loading and cleaning, FieldLoad PRO provides users with superior transportability and the gentlest of handling. The machine can provide throughput rates of up to 150 tons per hour.

Reliable performance is vital in modern agriculture, which is why the company insists on high-quality components for its machines. The development process for FieldLoad Pro highlights this ethos. Tong wanted a solution to precisely and reliably control the slewing position of the crop unloading elevator, in effect a type of cleated conveyor that expedites the efficient transfer of harvested, clean crops to an awaiting trailer.


“We decided on a turntable bearing for this task because, looking at the loadings and level of control required, it seemed the most reliable option,” explains Tong Engineering’s Product Development Manager, Neil Milson.

After a little research and advice, the company identified a KDM series turntable bearing from Rodriguez as its preferred option.

Rodriguez medium series KDM four-point-contact bearings have for many years been meeting requirements in a multitude of approved and economical turntable applications. As axial and radial loads – and tilting moments – can be absorbed, these bearings are robust and proven in the toughest of tasks. Featuring hardened raceways, KDM turntable bearings are available ungeared or with gear teeth as an integral part of either the inner or outer ring.

The KDM.I (internal gear) variant, supplied to Tong Engineering, features a diameter of 1094mm with standard clearances of ≤0.3mm (radial) and ≤0.53mm (axial), although reduced clearance options are also available.

“For this project, Rodriguez gave me all the support I could ask for,” says Mr Milson. “When I was looking at making the optimum selection, the advice I received was enormously helpful, pointing me in the right direction for this particular application.”

Originally, Tong Engineering had specified a larger bearing, but Rodriguez calculated that a smaller unit would still meet the needs of the task, thus helping the customer to reduce costs.

Each FieldLoad PRO requires one turntable bearing, and each bearing features a pinion (also supplied by Rodriguez – SS825 model). Rodriguez has already supplied four turntable bearing/pinion sets to Tong Engineering as it ramps up the production of its FieldLoad PRO, every one of which is built to order.

“The KDM turntable bearing has more than performed to its requirements,” concludes Mr Milson. “It is a robust piece of equipment that looks right for the job it needs to do. The quality of the product is really good.”


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