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.
The 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 good chemical resistance.
The 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 Dotmar EPP ’s Fluoro Pacific Australian manufacturing facility commenced manufacture of short cylinders of the material. The move dramatically reduced leadtimes, reduced costs and created other advantages for KETRON PEEK, in addition to its outstanding performance characteristics.
- High maximum allowable service temperature in air: 250 deg C for at least 20,000 hours
- Good chemical resistance
- Good resistance against boiling water and superheated steam
- Inherent low flammability (UL 94 V-O for 1.5mm) and low levels of smoke evolution during combustion
- Good resistance to high energy radiation (gamma and X-rays)
These qualities (and reduced lead times down to two weeks for cylindrical material) are in addition to the wonderful general positives of different thermoplastics, including light weight, low friction, non-corrosion, dimensional stability, cleanliness and static dissipation.
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.
But to get the good from KETRON PEEK, it is useful to be introduced to the different advantages of the major members of the family: KETRON PEEK-1000 (brownish grey or black) standard grade; KETRON PEEK-HPV (black) bearing grade; KETRON PEEK-GF30 (brownish grey) 30% glass fibre reinforced; and KETRON PEEK-CA30 (black) 30% carbon fibre reinforced.
KETRON PEEK 1000: Stock shapes of the KETRON PEEK 1000 grade are produced from virgin polyetheretherketone resin, and offer a high 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.
These features, added to KETRON PEEK 1000 good sterilisabilty by means of steam, dry heat, ethylene oxide and gamma radiation, make the grade popular in medical, pharmaceutical and food processing industries.
KETRON PEEK-HPV: The addition of carbon fibres, PTFE and graphite to virgin PEEK results in a KETRON PEEK Bearing Grade. The KETRON PEEK-HPV’s good tribological properties (low friction, long wear and high pressure-velocity capabilities) make the grade especially suited for bearing and wear applications.
KETRON PEEK-GF30: The glass fibre reinforced grade offers higher stiffness and creep resistance than KETRON PEEK 1000, and has a much better dimensional stability. KETRON PEEK GF30 is appropriate for structural parts carrying high static loads for long periods of time at elevated temperatures. The KETRON PEEK-GF30’s suitability for sliding parts, however, is to be carefully examined since the glass fibres tend to abrade the mating surface.
KETRON PEEK-CA30: The 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 specialist PTFE processor and fluoro polymer engineering organisation, Fluoro Pacific can also produce cylindrical material in a wide range of sizes.
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.
Local manufactured overcomes the problem of minimum order quantities (e.g. 1-3m), when users often only need to machine a few seals (i.e. only need 100-200mm). This innovation also:
- lowers leadtimes and airfreight costs. Short cylinders are available from overseas, but the service can be poor, and the leadtimes 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.
Fluoro Pacific can also bring local expertise to bear on particular applications. Fluoro Pacific’s sophisticated facility at Thornleigh in Sydney, can tailor PEEK compounds to suit particular performance needs.
Fluoro Pacific can also advise on replacing PTFE, where high mechanical loads are present or wear resistance is required, while maintaining good chemical resistance).