Sintered PTFE compounds.
Sintered PTFE compounds.
(OP)
Hello.
I was wondering if anybody is able to help me out with a dilemma.
At this time I am using compressors which have apex tips made out of PTFE with a 60% filling of bronze.
The displacer is a magnesium (8%) aluminium alloy and the housings are aluminium. We are subjecting the displacers to velocitys of 18 m/s.
We are having problems with the material shrinking and creating excessive wear on the displacer.
can anyone suggest a mix that would be more appropriate for this application.
many thanks,
Liam
I was wondering if anybody is able to help me out with a dilemma.
At this time I am using compressors which have apex tips made out of PTFE with a 60% filling of bronze.
The displacer is a magnesium (8%) aluminium alloy and the housings are aluminium. We are subjecting the displacers to velocitys of 18 m/s.
We are having problems with the material shrinking and creating excessive wear on the displacer.
can anyone suggest a mix that would be more appropriate for this application.
many thanks,
Liam





RE: Sintered PTFE compounds.
We can get over 75% of bronze into the nylon.
I expect it will have better dimensional stability and wear resistance at moderate temperatures, but I expect that PTFE is still better at very high temperatures, depending a bit on the mode of failure.
I am unaware of other suppliers, but maybe RTP, DSM or LNP can also supply.
Regards
pat
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RE: Sintered PTFE compounds.
I had been using a bronze filled Teflon with Molydisulfide added as a dry lubricant, but there's no comparison. The Vespel is an order of magnitude better in wear characteristics. It's also machinable, but very expensive.
RE: Sintered PTFE compounds.
Again thanks very much for the replys. I will let you know the outcome of some further RaD,
many thanks,
Liam
RE: Sintered PTFE compounds.
Hi thanks for all your help on this but unfortunatly due to budget restraints we are unable to use the Dupont material.
At the moment we are considering some other materials and are trying to find alternatives to te CR6100 series.
Ian how did the molydisulfide copper filled ptfe compare to ordinary copper filled ptfe?
Liam.
RE: Sintered PTFE compounds.
RE: Sintered PTFE compounds.
MoS2 generally does not do much for improving bearing properties in plastics, other than to act as a neucleating agent. Graphite however does usually help.
Carbon fibre can be very benificial, as can aramid fibre pulp, but these can be very expensive
Regards
pat
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