Transmissions ensure the beet (harvest) goes on

Edited by the Engineeringtalk editorial team Dec 17, 2004

Sugar beet harvesting is a tough, arduous and generally very dirty process that places special demands on power transmission components.

The world's annual consumption of sugar is now around 120 million tons, and is rising at a rate of 2 million tons per annum.

Around 30% of this consumption is derived from sugar beet, much of which is grown in the European Union, one of the world's top producers.

The fact that Europe is such a large producer has spawned a strong industry sector devoted to harvesting of the crop.

Leading the field in the technology are Dutch companies such as Agrifac/WKM with its revolutionary Hexa 12-row machine, which has revolutionised the efficiency of beet harvesting; and Vervaet, which has been producing big-tank sugar beet harvesters capable of topping, lifting, cleaning, loading and transporting sugar beet - in a single continuous process - for over 30 years.

Beet harvesting is a tough, arduous and generally very dirty process; environmental conditions are rarely optimal, with harvesting machines having to work either in rain-sodden, muddy fields, or in extremely dry conditions where dust poses a constant problem to equipment.

Obviously, these conditions place a premium on the performance of power transmission equipment used in the operation of the harvesters.

Yet despite all the rigours, Brevini has established a supply partnership with manufacturers of beet harvesters, based on quality, reliability and after sales service, which goes back nearly two decades.

Brevini has been supplying Agrifac/WKM with wheel drives since 1988; and Vervaet, since 1996.

Both companies use the drives for several reasons.

First, because they are wheel mounted in a package with a hydraulic motor, they permit a much neater design solution than axle drives and also provide greater clearance for rough terrain vehicles.

Secondly, the absence of an axle means that manufacturers have the flexibility to fit ultra-wide terra tyres to spread loading over a wider area.

Thirdly, with no standard axle to consider, the space under the harvester is free and can be used to transport beets from front to back of the equipment.

Forthly, the flexibility as regards brakes: the wheel drives can be supplied fully equipped with dynamic disc and parking brakes enabling the harvester manufacturer to conform easily to the specific laws in each country where the equipment is sold.

In addition to wheel drives, Brevini also supplies Vervaet with planetary gearboxes, and Agrifax with planetary gearboxes and BZ splitter boxes; the latter, "fit and forget" units that enable up to four hydraulic pumps to driven from a single prime mover.

The essential requirement for gearboxes used on beet harvesters is high reliability and high torque from a small operating envelope.

Brevini Benelux is able to meet these requirements and to comply with requests from customers to customise gearbox units.

Importantly, these can be supplied from stock and backed-up by full service support 24 hours a day, 7 days a week.

Both of these elements are extremely important to ensure that machines costing upwards of Eur 450,000 are not standing idle during the intensive harvesting season.

The planetary gearboxes supplied to both Agrifax and Vervaet are standard ED series units equipped with special seals and seal holders, and offering direct fitting for hydraulic motors.

Due to the poor working conditions, Brevini fits the gearboxes with a static sealing O-ring at the input and a special seal cover which allows play to the shaft of 0.5mm.

The combination of these protective measures helps to avoid the damage that the ingress of clay or other debris can do to the output seal of the gearbox units.