Fred Couch's customers at Rabbit Ridge Gin in Lepanto, Ark., don't fully understand how the powered paddle roll technology in the gin works, or that it increases capacity for the facility. All they know is that they've seen an improvement in turnout and staple length since the technology was installed three years ago.
The paddle roll device was invented by USDA/ARS engineer Weldon Laird at the Lubbock, Texas, ARS facility, through research funded by Cotton Incorporated. It is a spinoff of Laird's work on EasiFlo cottonseed — cottonseed which is treated with a starch and water coating after ginning to make it easier to handle for dairies and feedlots.
Laird was researching ways to remove excess fiber, or tags, from the seed. USDA scientists found that this extra fiber coming off the seed during the coating process resulted in clumping of tangled seeds.
Laird set out the remove the tags by running ginned seed through a second gin with a powered paddle roll and seed finger modifications. It worked so well that Laird started looking for a way to retrofit the technology on existing gin stands — in effect to remove the excess fiber during the original ginning process.
The successful venture now is marketed as the Power Roll gin stand and is being distributed through PRT Marketing. The president of the company is Laird's son, Russell Laird.
The technology does not require the installation of a new gin stand. Instead the existing gin front, or breast, is replaced with a new one that contains a larger seed roll area, a paddle roll to actively turn the seed roll and a seed finger roll.
Couch believes that the increase in capacity at Rabbit Ridge is due to the Power Roll's addition of a 30-horsepower motor to turn the seed roll. The gin has three 1973 Lummus 700 feeders and three, early-1970s model Continental 141 gin stands, which do not have a seed roll turning device.
“The ginning takes place by the saw causing the seed roll to begin to turn. So if I have 100 horsepower turning the saw, the 100 horses are also turning the seed roll.”
Adding the paddle roll technology allows all of the 100-horsepower motor to be used for turning the saw. “The more power you can put on the saw, the more seedcotton you're going to put through it. Our capacity increased a lot.”
In fact, capacity increased from 21.4 bales per hour in 2002 to 23.5 bales per hour in 2003, the year the technology was added. That increased to 25.11 bales per hour the following year with the addition of a higher-capacity press and moisture restoration. In 2005, capacity increased to 27.14 bales per hour with the installation of an improved gin front.
At Servico Gin, in Courtland, Ala., capacity increased from 26.5 bales per hour prior to installation of the power roll to 29.2 bales per hour after installation, even though the gin stands there do have a seed roll turning device.
Three years ago, the technology was installed on Murray 142 gin stands at Midnight Gin, Midnight, Miss. Ginner Robert Royal says, “There were some nagging engineering problems, but they were expected. But through it all, the seeds have been just buck-naked. That benefit goes directly into the farmers' pockets.”
Initially, Royal wanted to increase capacity without losing turnout, but that wasn't accomplished to his satisfaction until the end of the 2005 ginning season. “Weldon (Laird) and an engineer made some additional modifications and all of a sudden, it started ginning cotton like we had hoped it would, and turnout was still way up there. But it hasn't been through the paces of a full season yet.”
Royal noted that fiber quality improvements due to the technology “were nominal, but there wasn't any deterioration of quality.”
For Couch, the increase in capacity “has offset the labor costs and the increase in power and gas to dry. Just being able to gin another one or two bales per hour has allowed us to keep our per-bale costs stable.”
In addition, most of the gin's cotton producers — around 20 — “don't see nearly the deducts that they did prior to the technology,” Couch said.
According to tests conducted by USDA, PRT Marketing and the gin, turnout in the three years prior to installation of the technology averaged 35.7 percent. In the three years since the technology was installed, turnout has averaged 38.2 percent.
“Normally, there will be a tail left on the seed during the ginning process,” Couch said. “That tail essentially is excess lint. I was running somewhere around 12 percent residual lint left on the seed prior to the Power Roll. With the technology, I got that under 10 percent. In cleaning the seed better, that increased the return to the producer.”
The technology “won't take a 34 staple to a 35 staple,” Couch said. “But there will be more 35 staple length than what would come out of the conventional 141 Continental gin stand. I'm seeing a significant improvement in turnout. I also reduced my short fiber content from 10 percent to 7.5 percent.”
Couch has an idea of how the technology works because he sees many of the same benefits from slowing gin speed down considerably. “When you're ginning at a high rate, you're create a seed roll that is really packed. Sometimes it's packed so tightly that the saw cannot pull the seed to the ginning point. With the paddle roll technology keeping the flow of seedcotton broken up, every time the lint touches the saw, it's able to take it to the gin point.”
Greg Holt, USDA/ARS agricultural engineer in Lubbock, says some research on some of the Power Roll models has been mixed.”
On gin stand models where results were favorable, “studies showed that it did increase ginning rate and turnout. There were some fiber properties that appeared to be better with the technology.
“Like any new technology coming in, there were some rough spots. The wrinkles are being ironed out and the technology is turning the corner.”
Models that were having problems appear to have been fixed by a new design in 2005, according to Holt. “But we haven't collected enough data to definitely say that we found the problem.”
Holt said the ginning laboratory in Lubbock is expecting to collect that data with the coming ginning season.
“One of the potential benefits of the technology is the idea that it can control the speed of various components in the gin stand,” Holt added. “In the past, everything ran off one motor, which may not have been the best for quality.
“This gin stand could allow the ginner to change the speed of the individual components to accommodate different cotton varieties. Some of the research indicates that on a varietal basis, the setups probably need to be different.
“Basically, you're controlling processes within the gin stand, which is the heart of the gin, instead of controlling all those external things, and surrendering to the gin stand, which is going to run at one speed. One speed for everything isn't necessarily the best.”
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