August 20th, 2014
Saint-Gobain Seals' Rulon® J polymer material was recently selected to improve the performance of a bicycle rear shock absorber manufactured by a US bicycle component manufacturer at their production facility in Taiwan. Shock absorbers are a crucial part of higher-end bicycle suspension systems which increases comfort for the rider. Additionally, bicycle suspension systems help keep one or both wheels in contact with the ground to improve control and traction, and thus provide a safer ride. These features are especially beneficial for mountain biking and riding over rough terrain.
Since this high-end shock absorber uses hydraulic damping technology, a sealing component (glide ring) is required to prevent hydraulic fluid from leaking. Other requirements for this component include high wear resistance, gentle contact with an aluminum shaft, self-lubrication, and no misalignment. The manufacturer previously used a glide ring made from an alternative high-performance plastic; however, it did not meet the challenging leakage requirements.
Searching for a way to improve, the manufacturer tested Saint-Gobain Seals’ Rulon® J glide rings with positive results. Due to Rulon® J material being non-abrasive, the polymer works exceptionally well against softer mating surfaces such as aluminum. Its tribological properties demonstrate versatility in operating as both a seal and bearing. Their Rulon® J product also features one of the lowest coefficients of friction among commercially available blended PTFE materials, and it eliminates stick-slip for start/stop applications. Aside from being used on rear shock absorbers, Rulon® J material is also being used on the bogie of the newest 7000 series trains in the Washington DC metropolitan area (due to its enhanced stability on the curved tracks).
Saint-Gobain Seals is the only source of genuine Rulon® polymer material. This brand consists of a family of proprietary, blended PTFE materials for the most demanding applications and environments such as extreme dryness, cryogenic temperatures, water, steam and hydrocarbon fuel.
Each standard Rulon® material as well as hundreds of other custom Rulon® blends have been developed to meet a set of specific application requirements while also remaining versatile. For example, Rulon® 641 is ideal for food, beverage, and pharmaceutical processing applications (having achieved Regulation (EU) No. 10/2011 and USP Class VI and/or FDA Title 21CFR §177.1550 certifications); Rulon® W2 has one of the lowest wear rates in fresh water; and Rulon® 142 is the material of choice for machine tool guideways. Based on customer needs, Saint-Gobain Seals has been able to deliver optimal solutions in various markets with their vast portfolio of Rulon® materials and global R&D and manufacturing capabilities. In the Life Sciences market, Rulon® components were selected for high-performance clinical chemical analyzer systems and harmonic scalpel surgical tooling, and in the Aerospace market, the material was used on the Mars Rover Curiosity’s robotic arms, drill tools and surface removal tools.