TPEE offers performance consistency and long service life in railway springs

28 September 2006

Joint development between Durel GmbH and DSM Engineering Plastics has resulted in a range of railway side buffer springs, draft gears and, in more demanding safety applications, crash buffers capable of absorbing large amounts of energy. The designs combine metal with Arnitel® thermoplastic polyether elastomer (TPEE).

Acting as a spring, DSM Engineering Plastics says that Arnitel TPEE absorbs and releases energy in predictable ways over a long service life, helping trains to start, accelerate, decelerate and stop smoothly. Unlike metal springs, Arnitel TPEE does not rust, deteriorate, fracture or lose its springiness. In contrast to rubber, Arnitel TPEE does not lose its ability to act as a spring over time - the DSM material is claimed to have a field life of at least 20 years compared with 5-10 for rubber.

According to the company, elastomer springs made of Arnitel TPEE have a range of characteristics and offer advantages over other solutions tried over the years. These include excellent flexural fatigue endurance and high load bearing capability with low creep. They are also applicable in a temperature range from –60°C to +80°C. They offer good resistance against chemicals, grease, oil and solvents, as well as ozone and radiation. Other properties include good resistance against ultraviolet (UV) and hydrolysis for all-climate performance.