Serco Ryan's new long-life Viton based seals offer greater resistance to synthetic lubricants and higher shaft speeds

Citation

(2004), "Serco Ryan's new long-life Viton based seals offer greater resistance to synthetic lubricants and higher shaft speeds", Industrial Lubrication and Tribology, Vol. 56 No. 3. https://doi.org/10.1108/ilt.2004.01856cad.005

Serco Ryan's new long-life Viton based seals offer greater resistance to synthetic lubricants and higher shaft speeds

Serco Ryan's new long-life Viton based seals offer greater resistance to synthetic lubricants and higher shaft speeds

Keywords: Lubricants, Seals, Synthetics

Serco Ryan's new range of Rotary Shaft Seals from Dichta have been introduced to provide a higher performance alternative to traditional Nitrile seals which tend to fail prematurely when exposed to modern synthetic oils. The new Viton based designs also offer a longer service life at higher temperatures and an increased speed capacity of up to 6,000 rpm. Six models are available, providing varying degrees of pressure capacity, dust protection and resistance to misalignment. The standard size range will accommodate shaft diameters from 10 to 500 mm with most sizes held in stock (Plate 4).

Plate 4 Serco Ryan's long-life Viton based seals

Constant demand for longer life and higher operating speeds from machinery has led to the widespread use of synthetic lubricants, this is causing a serious problem with existing Nitrile seals, as synthetic oils weaken the material structure of nitrile-based products. The result is a premature seal failure that can cause extended down time due to leaks, product contamination and lost production. Nitrile seals are still being used in preference to higher performance sealing designs, using Viton lip elements, because of their comparatively low initial cost.

The cost implications of a seal failure though, far outweigh the cost of a better quality seal, making this practice a real false economy and underlining the reason for Serco Ryan's introduction of their new range of high quality Viton based rotary shaft seals.

Viton offers excellent resistance to both mineral oils and advanced synthetic types such as high- alloyed hypoid oil, also to ozone and weathering, providing longer operating life and a reduced chance of machine failure. Traditional nitrile- based seals typically have an operating temperature range of up to 160°C whilst Viton maintains sealing performance in applications where temperatures reach 200°C and shaft speeds exceed 6,000 rpm.

The new Dichta range includes over 200 metric sizes in six basic types, including seals with rubber covered metal inserts for speedy installation, types with dust lips for extra protection from contaminants and models with reinforcing caps to withstand pressures of over l0 bar. Stock designs are available off the shelf to fit bore sizes from 10 to 500 mm and with garter springs manufactured from either harmonic spring steel or stainless steel for more demanding applications.

For specialist applications, Serco Ryan also offer a large selection of non-standard seals with short lead times, an added benefit from sourcing components from within Europe. This facility allows manufacturers total flexibility of design in terms of shaft and housing sizes, as well as optional seal designs. Variations include twin lip types with two garter springs for extra protection, designs that offer right rotation, left rotation and bi-directional hydrodynamic lips. The hydrodynamic design produces a spiralling effect for recycling the lubricant from the lip back into the system, therefore minimising the risk of leakage and contamination.

Serco Ryan currently also stock around 80,000 separate product lines and their impartial technical advice is available to all customers and includes engineered sealing and fastening solutions as well as manufacturing cost reduction studies. Large stocks guarantee supply availability and a strict policy of only supplying quality products ensuring that Serco Ryan customers always have their expectations fulfilled.

For further information, contact: Barry Home, Marketing Manager, Serco Ryan, WYKO Seals, Hereward Rise, Halesowen, West Midlands, B62 SAN, UK. Tel: +44 (0) 121 5859303; Fax: +44 (0) 121 501 3014; E-mail: marketing@sercoryan.co.uk