John Deere's manager, technical service David Preece has received a special combine engineering award from the company, in recognition of his major contribution to the design of the Power Separator in WTS (walker tine separator) combines, and to other harvesting projects.
Incorporated as standard equipment on all John Deere 9000 WTS Series combines, which were introduced for the 2002 harvest season, the power separator lifts, stretches and opens the straw mat to allow more efficient grain separation, compared with the previous cross shaker design used in Z Series and 2200 Series models.
It was the result of a six year engineering project with the specific objective of improving combine performance in UK conditions. The design utilises a combination of conventional and tine separation technology to deal more efficiently with green and damp straw, and enhance grain separation on the straw walkers.
The combine's four stage threshing system begins with a large 660mm diameter cylinder and long 750mm concave. A rear beater and second concave provides additional threshing, and propels the crop to the extremely long 11-step straw walkers. Further separation is provided directly above the straw walkers by the tine power separator, which constantly and gently lifts and combs the straw mat to release trapped grain.
Key advantages of this system are that the full crop flow area is used for threshing and separation, so maximising combine performance; it's easy to change from crop to crop; and there's a low specific power requirement, which means lower fuel consumption.
"Our initial test designs adapted a baler pick-up, which was grafted into the back of the combine above the straw walkers so that we could learn more about the stretching and pulling actions on the straw," says David Preece, who has worked in service and customer support for John Deere Limited in the UK for over 30 years, specialising in harvesting equipment.
"The main problems we faced were the increased moisture and friction levels in green straw, typical of UK varieties that were being bred to become riper in the head but stiffer in the straw. This meant that grain kernels were not being separated as efficiently as possible, so contributing to greater losses out of the back of the combine or the need to reduce operating speed.
"Essentially the power separator allows faster forward speeds and reduces grain losses, and overall performance of the combines has improved by between 10 and 13 per cent compared with previous similar sized models. Not only does the new design enhance performance in UK conditions," he adds.
"This award demonstrates John Deere's commitment to developing and testing combines for UK conditions, and the valuable contribution our UK field and service staff make to machinery innovation and design," says Peter Leech, John Deere's manager, customer support.
"The power separator unit has been very successful and well accepted by customers, contributing to John Deere's increased share of the European combine market."
