Airless Irrigation Pivot Tires
There are few things worse than having to service a flat tire on an irrigation pivot in the middle of a humid cornfield in mid-July. If a flat tire isn’t discovered soon enough, the incident can ruin the tire or damage a gearbox, causing even more loss.
“With the exception of some implement tires, there isn’t a tire in the ag world that gets more exposure to UV rays and weather checking than an irrigation pivot tire sitting out in the weather year-round,” says Christopher Higgins of Lindsay Corporation. “As a result, you see some irrigation tires cracking and leaking before the tread actually wears out. Flats can also be caused by stubble damage, while others occur in rocky areas from ‘pinch flats’ between the rim and the tire.”
Fortunately, there are many airless tire options on the market with new innovations recently added by two pivot manufacturers. Their use comes with a warning, however.
“I can tell you that airless tires are harder on pivot drivetrains than pneumatic tires,” warns Higgins. “There are degrees to how much harder they are on drive components, and those tie directly to how rigid the tire is.
“There’s nothing better than a radial tire at 15 psi; there’s nothing worse than a rigid, nonflexible solid wheel,” he explains, noting that drivetrains have also improved over the years. “So there are trade-offs, even with our airless tires. Consequently, we try to be up front with customers about that. Still, we found that a lot of customers are willing to replace drivetrain components two or three years earlier than normal if it means they won’t ever have to deal with a flat tire again.”
Lindsay introduced its NFTrax airless wheel design as early as 2013. Based on a steel center wheel, it features a heavy-duty vulcanized rubber belt with a steel cable core that is tensioned over 10 winged drive points to apply even pressure across the entire belt surface. In addition to eliminating the potential for a flat tire, the belt also flexes to follow contours and to reduce stress on the drivetrain.
Last fall, as part of its latest lineup, Lindsay introduced the NFTrax 2.0, which features redesigned belt drive points and improved belt life. It also added the NFTrax Z-Tread, which features a more aggressive tread design for areas where more traction is required.
Lindsay’s field-testing results have shown the NFTrax wheel leaves a shallower track that is as much as 30% to 50% less than that of a standard 11.2×38-inch tire in similar operating conditions.
Higgins says a pair of NFTrax 2.0 wheels lists for a little less than twice the price of pneumatic tires, or around $3,800 per tower with the Z-Tread version being slightly higher.
valley airless tire
In the meantime, Valley Irrigation introduced its Valley Revolution airless tires in 2015 as an alternative to conventional tires. Valley claims the design is similar to those used on some forklifts. In other words, Revolution airless design features thick, rubber tires with webbing in the sidewall, between the tread and the wheel.
Valley says the aperture design provides flexibility over ridges and other obstacles to avoid overloading the drivetrain of the center pivot. Yet, it has more give than steel tires and will not slip on rocks or other objects in the field.
Both the Valley and Zimmatic option feature a nondirectional trend. This improves traction while reducing track depth by keeping mud in the wheel track, rather than pushing it out of the track like standard tractor tires.
Both options can be purchased as replacement tires or ordered as optional equipment on most of the respective manufacturers’ new center pivot models.
Poly Wheel OPTIONS
One way to gain the benefits of an airless tire without having to replace the entire wheel is to go with one of the polyethylene resin tires. Available from at least two companies, they’re designed to fit standard-size irrigation wheels, as the two halves are clamped around the wheel and bolted together. As a result, conventional tires that wear out or are damaged beyond repair can be replaced with a poly wheel.
One option is the RhinoGator No-Flat Tire offered by Dawson Tire and Wheel in Dawson, Nebraska. Distinguished by its green color, the RhinoGator is advertised as being constructed of high-density composite resins made from corn. The polyethylene also contains a high UV-protection package to increase the lifespan, which permits a five-year warranty. The price ranges from $435 to $495 each (depending on size and tread width and tread profile) with a price reduction for quantities of 16 tires or more.
A second polyethylene option is Mach 2 tires from Mach2 Company in Lake Mills, Wisconsin. Roto-molded from a resin supplied by Dow Chemical, Mach 2 tires are available in over 14 sizes with three tread designs for different terrains and soil types. The trademark white-colored tires also carry a seven-year warranty. Yet, they are advertised as being in the same price range as traditional tires in the same size. If desired, the tires can even be purchased complete with a furnished steel rim.
Both brands of poly tires feature nondirectional, self-cleaning tread designs and easy assembly. Due to a partnership with Reinke Manufacturing, RhinoGator tires can also be ordered as optional equipment on any Reinke pivot, saving the cost of a later retrofit.
steel wheel options
For those who like the idea of a solid steel wheel, there are at least two companies that offer galvanized steel options. One is Big John Manufacturing Company in Osmond, Nebraska, which manufactures wheels in 24- and 38-inch sizes, priced at around $700 and $850, respectively. The company claims that its steel wheels work in all soil conditions, including mud and sand, and utilize a wheel face designed to release mud. Of course, the obvious disadvantage is that you have to replace the entire existing wheel.
Another steel option is available from BB’s Metal Works in York, Nebraska. This company claims that its all-welded wheel weighs less than a standard 11.2-38 wheel and tire of the same height, and that the open design keeps the wheel free of mud. With 12 flat panels measuring 12 inches wide around its circumference, it’s also advertised to disperse the weight and to reduce ruts.
While there are probably other companies that offer poly and steel wheels, there are at least two firms selling another option. Amerityre sells a pivot tire that consists of 10 solid elastomer polyurethane segments attached to a galvanized steel rim. Priced at $1,399 each, these tires are available with standard and low-profile segments, which not only offer a bit of flex, but can be individually replaced in 30 minutes or less.
Another solution is offered by the Texas firm Armored Tire. For a price that ranges from $250 to $350, owner Warren Merrell will fill your existing pivot tire – even if it’s cracked or leaking – with a polymer product that is guaranteed to last a minimum of 10 years.