Custom Design Reaction Injection Molding of HELP® Energy Absorbing Bumper System for the Bus Transit System
The HELP® energy absorbing bumper, pictured, was designed and produced by Romeo RIM, Inc. for one of the largest transit bus manufacturers in the United States. This client wanted our company to redesign their existing bumper to reduce product weight and cost, while still meeting the American Public Transportation Association's (APTA) bus procurement guidelines (section TS 68).
Using our patented HELP® technology, we combined our unique engineering capabilities, in-house testing facility, and over 30 years of experience to develop a new energy-absorbing bumper. When compared with the client's previous bumper system, the new bumper provided 15% weight savings and 10% cost savings.
To begin this project, we first created a series of performance prototypes, ensuring that our new bumpers would optimize the energy absorbing characteristics for the rib and rail configuration. We then reaction injection molded (RIM) the bumper, meeting tolerances as low as ± .060". The part consisted of a two-piece construction, to allow for individual component service replacement. The finished bumpers were then in-mold painted for improved durability at reduced costs.
Romeo RIM produced this new energy-absorbing bumper to meet specific performance requirements, including:
5 mph barrier impact at curb weight
6.5 mph center strike impact of a 4,000-pound impact sled
5.5 mph corner strike impact of a 4,000-pound impact sled
All of these features allow for repeated impact with no damage to the bumper or vehicle.
As the leading supplier of energy-absorbing bumper systems for the transit, para-transit, and delivery truck industries, we used our technology and expertise to create a new bumper system that satisfied all of our client's performance expectations, and successfully reduced product weight and cost over our customer's previous model. Our redesigned bumper has now been applied to our client's new line of 30,000 lb curb weight busses.
HELP® Energy Absorbing Bumper System Specifications
This HELP® Energy Absorbing bumper is used within a Mass transit bus Application
Design for New 30,000lb Curb Weight Bus
Reduce Weight & Cost
Performance Prototypes Created
To Optimize the Energy Absorbing Characteristics for the Rib and Rail Configuration
Reaction Injection Molded (RIM)
Two Piece Molded Construction
Allows for Individual Component Service Replacement