Green about concaves? Not this Norfolk farmer!

Richard Ford was faced with a common enough dilemma:  replace his 03 combine with 2,200 drum hours or refurbish for another 2 to 3 year’s service. He output on his Claas Lexion 480 was falling and the original sieve concave was set on maximum to achieve an acceptable performance.

Richard chose to replace it with a heavy duty wire concave in Hardox 400 with increased separation area, parallel alignment to the drum and 2 extra bars at the back and 3 bars closer to the drum.

Manufactured by Combine Fabs, the only British manufacturer to offer dedicated concaves wear plate for consistent service, the concave is CAD designed and laser cut for uniform, true parallel fit. Set at 12mm, they feature an extra threshing bar in on the leading edge. Bars are spaced at 35mm over the first half and wider (40-45mm gaps) for effective separation over the back section. Wires are dropped 12mm from the top of the bar and spaced at 14mm gap throughout for improved grain separation. End plates are engineered from 10mm plate, interim bars from 6mm.

An exclusive 2 bar leading edge design is available on replacement concaves for Claas models.

So has it worked?

Richard grows around 1750 acres of cereal crops around Ashwellthorpe, South Norfolk. Whilst Norfolk has fared better than many counties with this year’s weather, many operators have experienced problems separating grain from green straw. Richard has not. When he encounters it he has simply opened up the concave without sacrificing its aggressive action.

Yields have increased by around 14%, typically 10.5 ton per hectare, being an ‘average’ result for a year like this. Richard has been harvesting up to 45 tons an hour with a 9m header, the combine’s overall output having increased by 15 to 20% on last year’s performance.

“I looked at changing this Claas for a similar 3 to 4 year old machine. Having had 4 harvests with it I was pleased to be offered just £6000 less than I paid for it. However the replacement would have cost an additional £100,000. Instead I spent £2100 including replacement rasp bars and the combine is good for the next 2 to 3 harvests.”

A further bonus has been less damage to straw from the combine when he is not chopping it.

Combine Fabs claim that their replacement concave collects more grain, makes less demands on the drum, minimises grain loss in the straw walkers and facilitates good forward speed and fuel economy.

The concaves have been tested on various machines to a universally good response, including John Deere 9000 and Z series, Claas Dominator 96 and Mega 218, MF 72, Laverda and Lexion Excelerator.
Combine Fabs Limited . Tel: 01636 702524 . Mobile: 07976 696712 . Fax: 01400 282100 .