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Variable stream, rotor loss, dense pack.

1049 Views 15 Replies 5 Participants Last post by  Don Boles
This is most likely a question for rice growers. With newer (rice) varieties yielding much more & the flag leaf being like a palm frond ….. to put in bluntly, S780/90’s in rice are atrocious. Rotor loss is horrendous …… & there’s seemingly not much can be done to alleviate the problem apart from drive slowly …….. & go down the road of making improved concaves & separation grates.
The rotors are variable stream jobs. They have a taper that goes way back to the third concave. The spiral pattern of the rotor elements is nothing short of resembling a big drill bit …… or auger flighting. And that’s what it does. Augers grain straight out the rear! No matter what rotor speed, concave position etc. etc. etc.
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For some reason, the “dense pack” kit is NOT INSTALLED in machines in this area for rice.
Obviously, the dense pack kit would slow material down & also push material towards the outside circumference of the rotor flow. And that’s what’s required to give at least a chance of stopping/reducing massive rotor loss in rice.

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So those with experience with variable stream rotors in rice, with dense packs installed ……. I’d appreciate your informed comments.
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I’d throw that rotor in the tip and put an original blunt nose rice rotor in, I know where there’s heaps of them............

That one above looks like it’s for harvesting watermelons or pineapples 🤦‍♂️🙄
I don't disagree with your prognosis …….. However, I doubt the owners would traverse that path.
Well several different options available for that rotor that aren't on the Tri-stream(bullet) rotor. If all you are harvesting is rice, you can put spike tooth threshing elements in and do a better job combing through the crop material as it threshes. I'll attach a picture. If your machine has a variable stream rotor in it then it should have the bigger separator grates in the back already installed. There are interrupter bars that can be put in on those grates as well if they aren't already in. They go on the right side in the first and third rows. You can play around with the interrupter bar configuration if you want but first and third row do pretty good. Up front you should have the aggressive feed accelerator with a combed floor under it. If you are only harvesting easy threshing varieties then pull the combed floor out. It is mainly for extremely hard to thresh varieties. There is a plastic insert kit that goes in the feed accelerator that keeps chaff out of it and throwing it out of balance. Yes you will have to go slow but we're harvesting 10,000lb per acre rice at around the 2.5-3.5 mph with 35' draper headers. You'll have to do the metric conversion there. One thing the variable stream rotor has that that picture doesn't show is the base of the threshing elements are welded to the rotor and the threshing element is just a cap for it. Check the position of the vanes in the back if they are adjustable. You want them in the standard position as opposed to advanced. The first pic is spike tooth threshing element. Second is interrupters that go into the separator grates. Third is plastic insert for feed accelerator. The fourth is interrupter bar on the grates. This is how we setup our machines for rice in gulf coast of Texas harvesting mostly hybrids. Hope all this helps and good luck with harvest.
Okay thanks. Firstly, it’s not my machine.……. just trying to help out a couple of JD owners in our area.
Convert to Metric numbers for you …… 😉 ….. 11.2t/ha, 4 K/hr, 10.5mt = 47t/hr.…. Which is quite acceptable & in the range of where a S780/90 would be , with around 1% loss - is my thoughts.
Rice in our area is high yielding medium grain varieties …… 12.5t/ha to 16.5t/ha (dry) is more the norm these days. Obviously, high yield equals high biomass. And all that has to processed through a machine - whilst retaining 99% of the grain.
Those that don’t harvest rice don’t really appreciate just how difficult & different rice can be compared to cereals. It’s a unique beast that needs specific “refinements” in machines to handle it.
In the early days of S series Rod Deere had a goal to increase throughput levels, losses be damned.
Trying to chase a certain German manufacturer.
What they learned from that exercise has carried over to X9 where they apparently also do care about losses.
Be interesting to hear how X9 performs in rice.
There‘s at least one X9 in this area in rice. It’s not a rice spec machine ……. so I’m guessing there'll be areas where “shirtloads” of stainless steel or bisalloy plate will be added after harvest.
No real reports of how it’s going or loss ……. apart from ….. “it eats the rice up” 🤷🏻‍♂️

So does the new preproduction CNH twin rotor …… that we’ve nicknamed “Megabine” …… ‘cause it’s fu..en big & seriously eats anything thrown at it!
I suspect that identical unit will wear two colors of dresses.
I believe that to be so. Different cab layout & different chopper/spreader I'm told. 780hp for the "baby" & 900 odd for those that subscribe to the "mine's bigger than yours" affliction!
Apparently to be released at Agritechnica.
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