With COG VarioPur, the independent seal manufacturer C. Otto Gehrckens presents a new product range in the premium segment. The three high-performance materials in the VarioPur series are based on thermoplastic polyurethanes (TPU/AU). Both the abrasion and the extrusion resistance are at least five times higher than those of the traditional material NBR, which has a Shore A value of 90.
Additionally, the three TPU materials have good gas tightness and a high level of tolerance to a wide range of gases – from oxygen and nitrogen to all synthetic hydrocarbons. They exhibit no brittleness as a result of exposure to ozone or oxygen. The product’s profile is rounded off by low swelling in mineral oil, hydraulic media and lubricating greases, generally good chemical resistance, and superb dynamic behaviour (blow-by behaviour).
In addition to the high-performance universal TPU material COG VarioPur 195, COG also has two new TPU sealing materials. COG VarioPur 295 has low temperature flexibility down to -50 °C.
COG VarioPur 395’s strength lies in its hydrolysis resistance: a quality that does not exist in this form in other TPU materials. This special TPU is stable in aqueous media, including oil-water emulsions (HFA), water-oil emulsions (HFB) and aqueous polyglycol solutions (HFC). It also exhibits resistance to other critical media, including biologically degradable oils (HEES and HETG), hardly inflammable liquids, triglycerides and synthetic esters of hydraulic oils or water-free media.
The COG VarioPUR TPUs are used in applications in mobile and industrial hydraulics, gas processing technology and gas spring technology, pneumatics, valve technology, the chemical industry and foodstuffs/pharmaceutical processing technologies and are available to order immediately according to the manufacturer.