Hendrickson USA, L.L.C., manufacturer of medium and heavy duty suspensions and suspension components, held a two-day training event for trucking alignment specialists at the Hendrickson Vehicle Suspension Institute in Woodridge, Ill., in October. The event, put on by ACOFAS (American Council of Frame and Alignment Specialists) (www.acofas.com), hosted 15 attendees from around the U.S.
The event featured classroom and hands-on training and updates to ensure proper procedures for handling suspension replacement and repairs for PRIMAAX EX, AIRTEK and STEERTEK NXT suspensions, as well as general information about Hendrickson’s Elastomers Business Unit.
The Elastomers Business Unit
In the elastomers session, Carmen Cardillo, Business Unit Director - Elastomers and Randy Zimmerman, Engineering Supervisor - Elastomers, discussed Hendrickson’s approach to the proper use of genuine parts for accurate servicing of Hendrickson products.
This seminar showcased the importance of replacing OE suspension products with genuine replacement parts. Otherwise, the suspension may not perform as originally designed -- causing a harsher ride, less articulation, higher stresses on other components, potential safety issues, and a voided warranty, the two pointed out.
Cardillo and Zimmerman stressed the importance of extensive testing and benchmarking during every phase of development of Hendrickson products, from vehicle testing and system level testing, all the way down to component level testing.
One aspect of this testing involves creating a stiffness “signature” unique to all components in a Hendrickson suspension. This signature defines the component’s optimized performance as it relates to compliance, energy absorption, load carrying capacity and durability.
Hendrickson designs for a specific component signature based on many critical requirements of the suspension. Zimmerman explained that other companies that manufacture aftermarket parts cannot replace the Hendrickson part with the exact same performance characteristics. This means, even if an aftermarket part looks similar to a Hendrickson part, it will not perform the same- thus not performing how the Hendrickson suspension engineers originally intended.
One of the many goals of the Hendrickson Elastomers Business Unit is to utilize the testing capabilities of the Hendrickson facility to determine the optimal performance of each component -- including bushings, bolsters, air springs and more. Zimmerman explained that the goal of Hendrickson’s engineering team is to determine "the best materials and designs for every application, whatever the right product is to provide the best suspension performance in the vehicle."
The use of different polymers
Zimmerman and Cardillo also addressed the use of different polymers -- including natural rubber and polyurethane -- when developing suspension components. Currently, Hendrickson primarily uses natural rubber for its components.
While polyurethane parts and components are often touted as being more durable, this is usually the result of the products being significantly stiffer, they noted. A higher stiffness component will transfer more load and NVH (noise, vibration & harshness) from the road to other areas of the suspension or chassis.
When using natural rubber parts and components, the natural rubber material is designed to provide compliance, absorb and dissipate energy to maintain the structural integrity of the entire vehicle.
"There's no one material that works for every application," said Zimmerman. This means that there's a place in the market for both natural rubber, polyurethane as well as other polymers. It's dependent on the use of the product and where it will be placed on the vehicle.
This isn't to say that Hendrickson will continue to exclusively use natural rubber. The Hendrickson Elastomers Business Unit has been created to review the performance of current and future suspension components, along with exploring different opportunities for component development using various types of polymers -- be it natural rubber or synthetic materials -- in order to optimize performance of their suspension products.