West Conshohocken, PA - (January 15, 2008) - When the Clifford Spring Company of Redditch, England wanted to develop a line of non-metallic energy absorbing springs for seals and backup rings used in the oil and gas industry, it chose VICTREXÂ® PEEK(TM) polymer. With its unique combination of high and low temperature resistance, inherent strength, and chemical resistance, VICTREX PEEK polymer has become the material of choice for the manufacture of seal and backup rings.
The weakness of seals has always been the necessary addition of a metallic energy absorber. Problems can occur if the seal wears and the metallic spring comes in contact with the shaft. This can cause irreparable damage to the shaft. According to Robert Navo, Global Applications Manager for Oil and Gas at Victrex, "The unique characteristic of springs made with VICTREX PEEK polymer is that as the seal wears and the spring comes into contact with the shaft, the spring will not score the shaft."
"The major benefit of using VICTREX PEEK polymer for the energy absorbers," said John Clifford, managing director at Clifford Springs, "Is that it eliminates the corrosion that can occur with ferrous-based components. VICTREX PEEK polymer resists virtually all aggressive chemicals, solvents and lubricants used in the oil and gas industry. Also, if the seal becomes worn and the energy absorber component is made from the same material as the seal itself, then there will be no damage to the shaft."
An additional benefit of using VICTREX PEEK polymer for the energy absorbers is that the overall weight of the seals is reduced due to the elimination of metallic components. "And there are no issues with differing rates of thermal expansion as both the seal and the energy absorber have the same coefficient of thermal expansion," added Clifford.
The energy absorber spring can be manufactured as a totally encapsulated item, which prevents the seal from lipping out, thus prolonging the life of the seal. Or, it can be manufactured as a Garter type spring which can be added to the seal as a secondary operation, following molding or machining of the seal. Using VICTREX PEEK polymer for the Garter type spring means that monofilaments can be produced in virtually any color, allowing instant identification and ensuring the correct energy absorber has been fitted to the seal.
Energy absorbers made with VICTREX PEEK polymer are available with outside diameters of 1.4 mm (0.05 in) up to 10.00 mm (0.394 in). The maximum single length that can be produced is 2.4 m (7.9 ft). This equates to a spring diameter of approximately 750 mm (2.5 ft). Multiple springs can be joined end to end to give a larger spring diameter.
Victrex USA Inc., a division of Victrex plc, is the sole manufacturer and supplier of VICTREX PEEK polymer worldwide. For more information on the properties and performance advantages of VICTREX PEEK polymer, please call (800) VICTREX or visit the Victrex website at www.victrex.com.
If you would like more information about this story, or if you would like to speak with a Victrex spokesperson, please contact Kris Jommersbach at [email protected]