Loading...
Solutions 2017-11-13T17:41:53+00:00

Matching / Exceeding the Deflection Profile and Dynamic Performance of a Pneumatic Tire

Challenge

An original equipment manufacturer of transportation systems (people movers/monorails) was seeking a customized tire solution to replace an existing pneumatic guide wheel in order to enhance multiple performance characteristics and extend the usable life of the wheel. The existing tire supplier only produced products on a mass scale and didn’t offer customized solutions for small unit sizes. Matching the dynamic performance and deflection profile of a pneumatic tire with a solid polyurethane material was a significant challenge in developing this customized wheel solution.

Solution

Our engineers developed and tested several polyurethane materials and tread configurations that would not only replace the existing pneumatic tire but also specifically address the desired performance characteristics. Our research and development professionals utilized our proprietary, custom-built testing equipment to conduct numerous types of tests over the course of several months, including: deflection profile testing, ultimate speed testing, ultimate load testing and simulation testing.

Our testing capabilities allowed us to simulate virtually all of the wheels operating conditions, including matching loads, speeds, and operating times by running test cycles of 8 to 16 hours, all of which were conducted at elevated ambient temperatures (125º+ F) repeatedly over several weeks. We ultimately developed a customized solution (incorporating a unique polyurethane chemistry and a new hub design) that provided a more desirable deflection profile than the pneumatic tire and matched or exceeded all of the desired performance characteristics. The solution increased the wheel life by 2.5 times and lowered our customer’s maintenance costs while providing increased comfort to passengers while in operation.

A Heavily Loaded Amusement Ride with High Wheel Usage

Challenge

This amusement ride was heavily loaded with extreme g-forces and heavy trains which resulted in significant wheel usage, especially in hot weather conditions. Wheels were lasting only 21 days during the summer with multiple modes of failure including blowouts, fatigue cracking and pinching off.

Solution

Our engineering and development professionals, working with the customer’s corporate engineer, developed an alternative wheel design and utilized a different chemistry (U3020). The redesigned wheel was required to realize the enhanced performance of the new chemistry. Testing of the new wheels yielded encouraging results as the average wheel life increased by five to six times. The new wheels, combined with the customer’s redesign of the trains, resulted in significant cost savings for our customer.

Introduction of a New Polyurethane Chemistry (U3020)

Challenge

The continued evolution of amusement rides, which has lead to the development of mega-coasters and hyper-coasters, resulted in increased dynamic pressures and wheel usage. The continued development of bigger, faster roller coasters with high g-forces throughout their ride profiles significantly reduced the life span of the polyurethane chemistries commonly used in the industry.

Solution

We developed, tested and implemented its new U3020 chemistry as a solution to the high speeds and loads of these mega-coasters and hyper-coasters. In its first installation, the new U3020 chemistry increased wheel life approximately 3.5 times, from eight to ten weeks to a full season (six months). Although U3020 is a more expensive material, the new chemistry provided significant cost savings to our customers through extended wheel life and reduced maintenance costs, labor and downtime.

A Complicated Wheel Design

Challenge

A customer’s initial wheel design, which consisted of several components (bearing, hubs, shafts, etc.), was complex and caused not only logistical issues, but also increased lead times and higher overall costs to replace worn wheels.

Solution

We designed an alternative wheel that solved many of the customer’s problems, significantly reduced costs and lead times, and virtually eliminated logistical issues associated with international freight and multiple components. This new wheel design was made possible by our proprietary bonding process which allowed the bearings to be fully encapsulated in the polyurethane wheel. The thoughtful solution also replaced many of the components of the initial design.

Replacement of an Old Pneumatic Tire

Challenge

A customer’s monorail system utilized a pneumatic tire that was discontinued and could no longer be replaced.

Solution

Our research and development team designed and developed a solid polyurethane alternative to the old wheel. The development of the alternative wheel required an entirely new hub design and a softer polyurethane material to accommodate the desired ride characteristics and speed, while carefully balancing the concerns associated with potential dynamic failures.