Urethane provides greater wear resistance than steel or rubber, at lighter weight & can be customized to meet individual specifications
Agricultural bulk handling equipment such as chutes, spouts, elbows and distributors can experience severe wear when transferring millions of bushels of ag products annually, particularly at transitions or rough areas, where “hot spots” of abrasion can occur.
In such cases, the bare structure of the equipment may not be adequately wear resistant and even traditional steel or rubber protective liners may insufficiently control the abrasion. This can pose a risk of costly spillage and production downtime for clean up and repair.
For such applications, sheets made from urethane (short for polyurethane) provide far better wear resistance than more traditional options such as steel or rubber. Urethanes are cost-effective, dependable elastomers that combine some of the performance advantages of high-tech metals, ceramics, and plastics, along with the flexibility and resiliency of rubber. Because of this, thinner cross sections can be applied at lighter weight, allowing easier installation.
Now this “tougher than steel” liner can actually be cut from full sheets of various sizes to fit the contours and shapes of high contact areas, so it can easily be glued, bolted, or welded to provide extreme wear protection wherever it is required.
While such liners are commonly cut to fit and installed onsite, custom liners made to fit important transitions or more complex configurations can increase reliability, simplify installation, and further reduce production downtime.
Extreme Wear Resistance
The outstanding abrasion resistance of urethane elastomers has led to many important applications where severe wear is a problem in industries as varied as agriculture and mining.
“Rubber is not as abrasion resistant as urethane, and fancy steel liners do not provide sufficient resistance either,” says Charles Pratt, Operations Manager at Kinder Australia, an independent supplier and manufacturer of conveyor and bulk material handling equipment.
Pratt turned to a proprietary urethane formulation called Kryptane, an extremely wear-resistant material for applications where abrasion, sliding, or impact occurs regularly, by Argonics, one of the U.S.’s largest producers of wear resistant urethane products. The liner is FDA Drygood Handling approved. Examples of its use include chute, bin and hopper liners; pipe, fitting and valve liners; and conveyor liners that withstand abrasive materials.
“In testing for some applications, we found that the urethane skirtings on the outside of a conveyor can last 10-15 times longer than rubber,” says Pratt. “Compared to a steel liner on the inside of a conveyor, a urethane liner can get 5-8 times the life.”
Because of its extreme wear properties, the urethane liner excels in grain handling applications. The urethane liner is also resistant to cracking, tearing, breaking, as well as sunlight and temperature cycling, which furthers its reliability in such settings.
“I have used Argonics lining material at our grain export terminal for over 10 years,” said Bill Hoffer, a retired chief millwright of CHS Inc., a farmer-owned cooperative working to help America’s farmers be more successful. “I have not had to replace any of these liners installed over the last 10 years. We export about 43 million bushels of grain through the system each year and the Kryptane liners show little sign of wear.”
In many such grain, seed, or rice bulk handling applications, self-installation of the liners is common, according to Doug Maves, an Argonics product engineer.
“When agricultural users only need minor trimming or simple cutting to line a straight chute or standard shape, they often measure and cut the sheets themselves onsite,” says Maves.
Standard sheet sizes are 4’x8’, 4’x10’, 5’x8’ and 5’x10’, in thicknesses from 3/16” to 1”; rolls are also available – 4’x25’ up to 5’x100’. The material can be installed/fastened using a bolted technique, glued or welded in place to create rugged and durable lining for chutes, spouts, and other agricultural bulk handling equipment. Polyurethane coated bolts are also available when using a bolt-in technique.
Maves notes that plain liners are suitable for lighter duty applications. For heavier duty applications, he suggests using a backing to prevent potential stretching and to help improve the integrity of the fastening method.
“When gluing a liner to a structural surface, fabric backed sheets can achieve a stronger adhesive bond,” says Maves. “When bolting a liner, expanded metal or solid metal backed sheets can provide extra strength and rigidity.”
Custom liners are also available for more complex transition points. These can be engineered and manufactured to the finished size/geometry required by the manufacturer to easily drop into place. This minimizes production downtime along with eliminating the need for measuring, cutting and/or trimming the standard sheet product in order to fit the application.
“If the liner requires a tighter fit, a complex shape, or multiple pieces to fit certain transition points, then working with the manufacturer for a custom fit may be a better option,” says Maves.
He notes that such custom fittings increase liner reliability as well as reduce waste, installation time, and production downtime, since fewer sheets, fewer cuts, and less adjustment is needed for onsite installation.
The process for customizing liners is quite simple for agricultural end users.
According to Maves, the end user typically provides a sketch, drawing, or photo of the bulk handling equipment to be lined, along with dimensions and notes. The manufacturer then finishes the drawings and provides a quote; if the end user approves, the liner is completed, shipped, and is ready for installation when received.
Whether used as standard or custom liners, urethane’s extreme wear resistance can offer agricultural design engineers, equipment manufacturers, or end users years or even decades of trouble free handling of bulk products.
For more information contact Argonics, Inc., 520 9th St., Gwinn, MI 49841; call 800-991-2746; email firstname.lastname@example.org.