Help: Advanced Polymers - Selection and Comparison

[ella0509]

Hello, I wonder if any of you guys can help point me in the right direction. I'm looking for a material with the following parameters:

> ~2" Diameter Tube
> Excellent Chemical Resistance
> Low density
> Electrical Insulator
> 200 Deg. C Service Temp for <15mins
> 1 Bar.G internal pressure
> 100mBar internal Vacuum
> Pressure & Vacuum will be cyclic in nature
> Can be machined (Sealing features etc)
> Possible need for Epoxy style bonding


I've been suggested PEEK as one option, but the cost is quite high. Are there any others that may well meet the required specification, but come in at a lower cost?

Also are there any good reference sites / documents out there that compare the parameters of advanced polymers but include cost guidance?

http://www.dotmar.com.au

is excellent, but I can't see any cost info.

Regards,
Lee

 

[patprimmer]

How many do you want.
What lengh tubes.
What wall section.
What chemicals.

Depending on how you answer above,FRP, Phenol formaldehyde, GF nylon 6.6 or GF nylon 4.6 or GF aromatic nylon, GFPPS, GFPTFE

Regards
Pat
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[ella0509]

Hello Pat, thanks for your response.

We're completely at the concept stage at the moment, and hence fully defined specification is still not quite there.

> The length our R&D guys are asking to test with is around 400mm.

> The wall section will need to be sufficient to withstand the pressures so is material choice dependent, so I don't have a figure for that at the moment.

> Its for an air filtration system, so a broad range of chemicals, Acids etc could all be present at some point. I have the chemical list, but I am unable to disclose.

It was more some other alternatives to look at that I was fishing for, and you've given me some of those, so thanks. What I'm still lacking though is a comparison of purchase and processing costs associated with each type.

Regards,
Lee

 

[ella0509]

Sorry, missed quantity!

Initial prototype stage could be upwards of 100 tubes maximum. Full production could well be in the 1000's possibly even into the 10,000's.

Regards,
Lee

 

[unclesyd]

We have some similar size cylinders made from
Ryton (PPS).

Here is the home page for Ryton.

http://www.cpchem.com/enu/ryton_pps_tl_rod_plate_tube.asp

You might want to touch base with the following company as they carry a complete cross section of engineering plastics.

http://www.quadrantepp.com/default.aspx?pageid=46

The following can make good sized cylinders from most moldable plastics. Check the available dimensions in the paragraph.
"Compression Moulded Plastics"

http://www.cdipolytek.com/processes.html

This company did offer tube/cylinders

http://www.tetralene.com/Ryton.htm

 

[CoryPad]

I think the temp limit is the biggest constraint. PEEK, PPS, PA are suitable thermoplastics; phenolic, polyester and epoxy suitable thermosets. The thermoplastic materials should have lower costs due to automated series production, but thermosetting composites are used, especially for low-volume applications. You will need to work with various suppliers to get costs, it is practically impossible to give accurate numbers. Qualitatively, price for thermoplastics would be PEEK > PPS > PA; for thermosets, epoxy > polyester = phenolic.

Regards,

Cory

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[patprimmer]

With our list of pressure and temperature with all sorts of chemicals, I am leaning toward an FRP tube with a TFE liner.

The PTFE for the chemical and temperature resistance and the FRP to give the required physical strength. Filament winding might work to apply the FRP.

When comparing temperature resistance and chemical resistance data, remember to allow for stress and for the chemicals at the temperature involved.

Regards
Pat
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