Higher loads and better wear key to success of enhanced sealing

Paul Boughton
Seal manufacturers are focusing on new products that wear better and can handle higher loads. At the same time, the market is consolidating. Sean Ottewell reports.

Enhanced PTFE materials from Quadrant, available in full production sizes, have been broadened with two new grades: Fluorosint HPV and Fluorosint MT-01.

US Food and Drug Administration (FDA) compliant Fluorosint HPV is a mica-filled high performance bearing grade that can deliver a pressure velocity (PV) performance improvement of more than 40 per cent over other PTFE materials according to in-house tests conducted by Quadrant.

The company says that parts made of Fluorosint HPV can withstand higher load and velocity while delivering better wear resistance, enabling longer part life compared to existing FDA compliant PTFE-based materials. The product was especially developed to meet the demands of high performance bearing applications where other, low-tech PTFE formulations would exhibit premature wear or cannot perform. These characteristics together with FDA compliancy open up interesting new options for engineers and manufacturers.

Stephan Glander, global director research & market development with Quadrant comments: "Simply put, parts machined from Fluorosint HPV last longer than those made from many of the alternative filled PTFE materials on the market today. Fluorosint HPV can replace bronze, steel and powdered metal parts and deliver performance gains in wear life and system performance. Typical applications include thrust washers, wear guides and seals."

The second new grade addition, Fluorosint MT-01 (Fig. 1), combines exceptionally high temperature resistance with low deformation and low coefficient of linear thermal expansion (CLTE).

Flourosint MT-01 was developed for high temperature applications such as bearings, seals and wear surfaces where higher loads are present. Ovens, dryers and linear positioning equipment exposed to elevated temperatures are all ideal applications for this ultra-performance grade.

At the same time, Aberdeen O-Rings & Seals has announced a new explosive decompression resistant perfluoroelastomer for seals used in ultra-aggressive, processing applications.

The Perlast G92E elastomer combines high levels of chemical resistance with an increased explosive decompression capability, setting a new performance standard for perfluoroelastomer seals in pumps and valves in oil and gas exploration and processing (Fig. 2).

Perlast G92E is part of the EnDura range of elastomers designed specifically for the oil and gas offshore industry. The polymer's high fluorine content renders it inert to a wide range of liquids and gases such as hydrogen sulphide and methane encountered during oil and gas operations. Suitable for environments up to 260°C, G92E has tested successfully in a range of high temperature, high pressure and aggressive gas conditions, including those described in NORSOK M710, and is currently undergoing further industry and international explosive decompression standards testing.

EnDura is a family of different elastomer types that offer superior chemical resistance compared to conventional explosive decompression grades, greater high and low temperature capabilities and are tested to the major international explosive decompression standards such as NOROSK M-710. The EnDura range includes HNBR, TFE/P, and FKM elastomers.

"Perlast G92E is an important development which expands the Endura range's capability into the upper end of the performance range for elastomers in oil and gas processing," says Rachel Armell, business manager, Aberdeen O-Rings and Seals.

Meanwhile US company WL Gore & Associates has introduced new, enhanced GORE GR sheet gasketing. The enhanced performance attributes represent a technical breakthrough for PTFE gasketing in the area of dimensional stability - a key attribute of important value to users.

Featuring a novel, patent pending technology, the sheet gasketing material's ability to withstand creep relaxation means better performance at elevated operating temperatures. Plus its greater sheet integrity helps prevent fractures that can occur due to improper gasket loading in exceptional circumstances such as extreme flange deviation and misaligned flanges.

With the newly enhanced performance properties, industrial users will benefit from greater reliability and fewer operational 'surprises' from flanges.

According to Rob Haywood, Gore product manager, the new enhanced GORE GR sheet gasketing product offers several key advantages for plant operators, including reducing sealing system costs, minimising downtime, and optimising personnel safety.

Consolidation too

Danish company KE-Burgmann, a subsidiary of the EagleBurgmann Group, has acquired 100 per cent ownership of Californian company Expansion Joint Systems (EJS). KE-Burgmann EJS will be operating in the future with EJS founder Neville Barber as general manager.

"This acquisition has considerably boosted our chances and growth potential in the booming oil/gas and petrochemicals markets such as those in the USA or Middle East. Our combined engineering and production know-how together with our strong service orientation will significantly strengthen our position as the most versatile manufacturer in the global expansion joint market", emphasises Peter Nielsen, ceo of the KE-Burgmann Group.

Earlier this year, Garlock (Great Britain) Limited, acquired PTM (UK) Limited, a manufacturer and distributor of sealing solutions. The acquisition supports Garlock's growth in an important market and complements its acquisition of Northern Gaskets and Mouldings in December last year. PTM is a rubber moulding and gasket fabrication company dealing specifically in custom sealing solutions, gaskets and insulation materials. It distributes high quality seal products and gasketting materials, including Garlock GYLON and Pharmaseal. Employing 40 people over two sites in Stockport and Wrexham, England, PTM has established a reputation for high quality 'on demand' service and specialist expertise in the chemical, pharmaceutical and OEM markets.

The acquisition brings the benefits of Garlock's strong innovation, research and development and lean manufacturing skills directly to the end user of its sealing technology solutions. It also enhances the products and services Garlock provides to its customers, through an increased focus on operational excellence.