Comparing Vermeer's RTX1250 Plowing on Tires, Rubber Tracks, and Steel Tracks (pg. 2)

Sept. 28, 2010
 
 
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Tractor Traction Test Course
The Plowing Tractor’s World

To simulate the ever-changing environment of the plowing tractor, the test course included 200 feet of hard packed soil (an access road); a 100-foot, 90-degree radius in moderately packed soil to simulate a cul-de-sac; another 200 feet of moderately packed soil with a steep, 48-inch-high berm at near the mid-point; 200 feet of wet clay (the “Swamp”) with a slick surface of drilling fluid from a horizontal drill being tested nearby; and 300 feet of rough terrain ranging from moderate to hard-packed soil.

Professional operator Chris Anderson pulled a 42-inch vibratory plow through this 1,000-foot course as quickly as good operating practices allowed. The plow was set in its float positions for both depth and steering. Anderson repeated this process three times — using a machine equipped with rubber-track modules, a machine with steel-track modules and a machine with tires. We timed the machines through each 100-foot segment of the course, then calculated approximate production rates for each. Our objective was simply to get a look at the relative performance of the RTX1250 with each of its three undercarriages.

The accompanying table presents the data. When plowing in hard-packed material (segments 1 and 2), rubber tracks produced 53 percent more than the wheeled machine, and steel tracks produced 22 percent more than the rubber-tracked machine.

In the really tough going of the “Swamp” (segments 6 and 7), the wheeled machine soon dug itself in and could not move the plow. Rubber tracks worked through the slop, but at a slow pace, averaging about 9 feet per minute. The steel-tracked machine, however, averaged 56 feet per minute through the Swamp.

“The advantage I see with the rubber-tracked machine,” says Anderson, “is that it runs anywhere. With a rubber-tired machine, you have to pick your spots [to plow], because you know that if you run into mud or a soft ground, you’ll lose production. With rubber tracks, you don’t have to be as selective about where and when you plow, and you get more days in the field.”

And what about the steel tracks?

“Your mobility with a steel track is limited, of course,” says Anderson, “because you can’t drive the machine to the next job. But the steel undercarriage makes for a cross-country machine, and if you’re in the mud, it’s the one to have.”

Practical benefits

Early in the year, when the temperature in Pella, Iowa, (Vermeer’s hometown) was around zero and the ground solidly frozen, we visited with Jon Kuyers, manager of ride-on trenchers and compact equipment, about the design of the RTX1250 and its undercarriage options.

Machines like the RTX1250 are used in trenching, plowing and rock sawing, said Kuyers, and each may have different traction requirements depending on ground conditions.

“In trenching, it’s really a mixed bag, because of the various terrain the machine encounters,” says Kuyers. “Often a machine like the RTX1250 on tires has more tractive effort than required when pulling a trencher, because the trencher can work only so fast. But with a plow, too much tractive effort is never a problem. The vibratory action of the plow is an assist, of course, but it’s the actual pulling force of the tractor that moves the plow through the ground.”

During development and testing of optional undercarriage systems for the RTX1250, Vermeer learned that rubber-track modules are effective in both trenching and plowing. When trenching, the modules help maintain production in applications where poor ground conditions and steep terrain are detriments; and when plowing, the rubber-track modules generally boost production, especially when surface conditions turn slippery.

According to Kuyers, an unexpected benefit derived from the rubber-track modules is their positive affect in rock sawing. Because pneumatic tires can flex, the rockwheel may bounce, momentarily losing contact with the face. The rubber tracks’ firm, flat-footed stance pulls the saw consistently into the cut. Production benefits, as does the smoothness of the cut and life of the saw and cutting teeth.

Overall, says Kuyers, equipping the RTX1250 with tracks will allow contractors to extend their working season and to maintain or increase production in a broader range of conditions. Tracks, he says, have allowed some contractors to take on jobs that had been beyond their capabilities.

Comparing pulling power

CE editors returned to Pella in early May to observe first-hand the performance and potential production differences among the RTX1250’s undercarriages. Kuyers had arranged to have plow-equipped units available with the three different undercarriages, and had created a 1,000-foot test course for the machines to traverse.

The course represented varied operating conditions, including plowing a hard-packed road, working through a cul-de-sac, climbing rough terrain and slogging through slippery, soft conditions that challenged flotation and traction. Each of the undercarriages tried the course, and we recorded the time each required to traverse each section. This simple demonstration allowed us to calculate a production rate for each undercarriage in the various operating conditions, and overall, to asses their relative performance as conditions changed. The accompanying sidebar, “The Plowing Tractor’s World,” gives the details.

To make the comparisons an “apples-to-apples” event, professional operator Chris Anderson ran all the machines. Anderson is a long-time employee of Mid American Energy, based in Des Moines, and typically runs either a vibratory plow or a horizontal directional drill to install utilities. We’ve included some of Anderson’s observations and comments in the sidebar, but it’s fair to say here that he’s a fan of the tracked machines.

Having operated plows with a single, long track on each side of the machine, Anderson sees the four tracks’ ability to plow around a radius like a wheeled machine and climb obstacles without break-over as clear advantages.

“Also, since you can crab steer with the quad-track system, you can sometimes tip the tracks just a bit into a hill and maintain a straight line across the slope.”

“Another consideration for our company is restoration. The rubber track doesn’t tear up the ground as much as tires. After we’ve plowed, we come right back over it with the tracks and level it out. Sometimes you can hardly see that we’ve been there.”

Without giving too much away here, we can say that the overall production of rubber tracks is superior to wheels, and steel tracks out-work rubber tracks.

Of course, enhanced capability carries a price tag. Compared to an RTX1250 equipped with rubber tires, expect the list price of the same machine with rubber tracks to be around 30 percent more. If you want steel tracks, expect to pay about 20 percent more for the XTS1250 than the price of the rubber-tracked machine. As always, price is relative to performance. Undercarriage options now allow RTX1250 customers to decide how much traction they need — then to pay accordingly.

Plowing Production (ft./min.)
SegmentTiresRubberSteel
1145265
2165464
3307786
4294453
5147895
61173
7738
86174
95668
105365
Total time for 1,000-foot course (min.) 3716