Plastics Prove Viable Alternatives to Metals in Extreme Applications

Right up near the top of the performance pyramid of advanced engineering plastics is an outstanding material that challenges Australasian preconceptions about the use of plastics instead of metals in extreme applications.

This aristocratic KETRON PEEK family of plastics is based on polyetheretherketone resin, a semi-crystalline advanced material that exhibits a unique combination of high mechanical properties, temperature resistance and excellent chemical resistance.

The superbly tough and impact-resistant KETRON PEEK family is finding expanding markets in the engineering and manufacturing of electrical, electronic, food and beverage, dairy, medical, process and high temperature components, including seals, wear bands, bobbins, bushings, rollers, gears, valves, pumps, filtration plates, heat exchangers and equipment subject to repeated cleaning, sterilisation, boiling water and steam.

Access to the material for a wide range of applications was expanded recently when • Very high maximum allowable service temperature in air: 250 deg C for at least 20,000 hours
• Excellent chemical resistance
• Excellent resistance against boiling water and superheated steam
• Inherent low flammability (UL 94 V-O for 1.5mm) and very low levels of smoke evolution during combustion
• Excellent resistance to high energy radiation (gamma and X-rays)

The further advances KETRON PEEK offers are fundamental to the inroads the material has made in international engineering - and is poised to make into an Australasian engineering ethos that is overwhelmingly metals-focussed and alternatives-blind.

KETRON PEEK 1000. Stock shapes of this grade are produced from virgin polyetheretherketone resin and offer the highest toughness and impact strength of all KETRON PEEK grades. The composition of the raw materials used for the production of the KETRON PEEK 1000 natural stock shapes complies with the directives of the European Union and with the American FDA regulations concerning plastic materials intended to come into contact with foodstuffs.

KETRON PEEK-HPV. The addition of carbon fibres, PTFE and graphite to virgin PEEK results in a KETRON PEEK "Bearing Grade". Its excellent tribological properties (low friction, long wear and high pressure-velocity capabilities) make this grade especially suited for bearing and wear applications.

KETRON PEEK-CA30. This carbon fibre reinforced grade combines even higher stiffness, mechanical strength and creep resistance than KETRON PEEK-GF30, with an optimum wear resistance. Moreover, the carbon fibres provide 3.5 times higher thermal conductivity than virgin PEEK, dissipating heat from the bearing surface faster.

A recent innovation is local manufacture of short cylinders, which help reduce costs and expand applications by minimising waste of this superior but higher cost material.

• lowers leadtimes and airfreight costs. Short cylinders are available from overseas, but the service can be poor, and the leadtimes very long).
• saves costs compared with rod, because cylinders weigh less and therefore cost less
• saves costs also because users buy only the length they need, not a full length of tube.