If you’re looking to replace tires on your irrigation system, the decision can be daunting when balancing it with farm income these days. Whether your problem was flats, ruts, or something else, there’s likely a tire solution that can alleviate those issues. To give you a better idea on how to get the best value for money, here’s an overview of the tire and wheel options available for center pivot systems.
No-Flat Solutions
1. Plastic Tires
Manufacturers offer roto-molded plastic tires made of high-density poly. These tires simply bolt onto the irrigation system’s existing rims, eliminating the need to purchase rims with the tires, although they can be purchased as assemblies for quick unbolt and rebolt. The main benefit of plastic tires is that they never go flat. Not only does this save time repairing flats, it also eliminates crop damage from bringing in service equipment to repair those flats. Another advantage of this tire is its non-directional tread design, which allows it to be used universally in circles or wipers.
Plastic tires are fully UV-treated, allowing them to last longer than rubber, according to lab testing. The plastic concept is fairly new, but accelerated testing has proved a 10-plus-year lifespan is common for these types of tires. They have a mid-range cost comparable to that of a domestically manufactured rubber bias tire.
One of the main challenges of plastic tires, however, is the possibility of causing ruts in heavier soils that are saturated with water. As a result, they’re not generally recommended for high-water applications or heavy, gumbo soils, where they may dig in more than rubber tires. This is due to their relative inflexibility. In lighter soil types, with normal water application practices, the track is often the same as rubber tires.
2. All-Steel Wheels
Another no-flat option is steel wheels. Understandably, they have a higher up-front cost, since the grower has to purchase an entire wheel, rather than just the rubber or plastic to go on an existing rim.
Additionally, there are several issues commonly associated with steel wheels. Welds may break, the wheels can rust, and customers often experience longer lead times. Nonetheless, the solid steel construction allows them to stand up well to heavy applications such as corner arms. Some farmers swear by steel, while others have had poor experiences, making it difficult to recommend this product across various applications. In the end, the decision to go with steel wheels generally comes down to personal preference.
3. Tracks
There are two types of tracks for irrigation systems: over-the-tire (available in plastic and metal) and complete track systems, which replace the entire wheel assembly. Over-the-tire tracks, which are installed over the existing tires, are only available on certain types of tires, particularly recaps with limited availability.
Track systems have the largest footprint and offer the most flotation when working in difficult soil conditions, but they are hands-down the most expensive option on the market. In addition to the high purchase price, track users can expect to pay more for maintenance, because track systems have a lot of moving parts. Depending on the amount of use, some users have to replace wear parts every three to four years. If over-the-wheel tracks are used, the moving parts and rubber tires are also subject to wear and air leakage.
Pneumatic Tire Solutions
4. Bias Tires
The most common tire option on irrigation systems is bias tires. All irrigation manufacturers offer bias tires as standard equipment. These are the cheapest tire option, and they are available in many sizes to accommodate standard rims as well as larger specialty rims used for increased flotation and heavier loads. Rubber tires are also sold in assemblies, which are very handy to have on hand to quickly unbolt and rebolt during irrigation season.
There is a wide variety of manufacturers who produce bias tires. Domestically manufactured tires can be up to 30 percent more expensive than imports. In the past, domestic tires typically came with better warranties and warranty support, but in recent years import tire quality has improved. In fact, certain import brands now offer five-year warranty and domestic warranty support.
Some growers may also be familiar with recap, or retread, tires. These were more common in the 1970s and ‘80s than they are now. Back then, there was a greater supply of high-quality tire casings from the trucking industry that were being recapped for use on irrigation systems. As tire technology has improved over the years, tire carcasses now have many more miles (from extended use in the trucking industry), making the recaps less dependable in the field. There is a trend toward lower-profile, wider tires in the trucking industry, which also limits availability. As a result, fewer suppliers sell recap tires competitively today.
Regardless of which type of bias tire is used, air is a big disadvantage, since a flat tire can cost a lot of money in repair and downtime. They generally require tubes, which add cost. Another drawback is the lack of flotation due to higher inflation pressure needed keep the bead seated. Because of the old technology found in bias tires, flotation is reduced as the tires are inflated and lose footprint.
5. Radial Tires
Radial tires take advantage of modern tire technology. They run at a lower PSI, keeping the tread face flat on the ground to maximize their footprint, traction and flotation. Because radial tires flex, the tire cleans out the better than bias tires.
Radial tires are constructed with tighter bead tolerances so they can be run at lower air pressure without the risk of bead breaks, eliminating the common problem of bead leaks in pivot tires. Also, manufacturers believe in their performance so much that they offer warranties of up to eight years for radial irrigation tires.
Cost is a primary difference in purchasing radial tires. They are priced about 20 percent higher than bias tires and approximately 10 percent higher than plastic no-flat tires. However, when you factor in the total “cost to own” as explained in the last section of this article, it may be the best option out there.
Now You Know (sort of)
After getting an understanding of these five types of irrigation tires, the next step is to work with trusted suppliers who can help you determine the best option for your operation. They can help you reach the right decision based on a combination of factors, including soil types and local farming practices.
In the end, you should calculate the lifetime cost of a particular tire or the cost to own as opposed to looking only at the initial cost of purchasing that tire. If you expect a tire to last five years and the initial cost is $500, then the lifetime cost of the tire is $100 per year. Right?
Maybe not. Did you factor in the cost of a flat repair? What about downtime? What about ruined crop or lost yields? For the sake of this exercise, say those cost over a five-year period were $100, $60 and $210, respectively, then the lifetime cost of the tire is now $870 over a five-year period. How does that compare to a different tire option on the market?
Do the math to figure your total cost to own, then choose the tire option that makes sense for you.