Woven wire mesh protective coatings

[Robert Alford]

Improve filtration efficiency and extend the longevity of Woven wire mesh Stainless Steel filters.

Hello my name is Robert, I am a student at Loughborough university currently working with a filtration company to improve filtration efficiency and extend the longevity of Woven wire mesh Stainless Steel filters in a range of applications but particularly protection from harsh corrosive chemicals (e.g. chlorides, acids).

I have read a number of threads and there apears to be some real experts who post here.

Corrosion in these harsh enviroments seems to be unavoidable without a protective barrier (coating).

My current research has yielded a number of possible coatings however the thickness of coating required appears to be an issue as the aperture of the mesh must have the minimal reduction in size possible.

My query is what coatings can people suggest which can be applied in thin coatings to protect the Stainless Steel from harsh corrosive chemicals such as chlorides and acids?

Current research has sugested the Fluoropolymer family (mainly PTFE), SiO2, TiN, Aluminium, TiO2, ZnO (not using the photocatalytic property) etc.

Any opinions on the above coatings and other ideas to solve this corrosion problem would be much appreciated.

Thank you

Robert

[MichiganMan]

Welcome Robert,

You'll need to be a bit more specific if you can. Chlorides and Acids doesn't really tell much about the application.

What size solids are you trying to filter (or pass)?

Does the mesh have to be a specific grade of stainless?

How thick can/should the coating be?


Dependent on the details it may be as simple as a liquid applied barrier coating (an oxirane or something in that vein) or it might be more complex.

[Robert Alford]

Thank you very much for your message
Sorry for delay in reply I went to see the company again yesterday.
The company provide filters to a range of companies some of the resent enquiries that would benefit from a protective coating include filters in the make up business, cleaning liquids ( i.e. fairy liquid), mesh baskets ( larger 10 mesh used here with an aperture of 2mm) used in sulphuric acid.
The coating thickness needs to be as thin as possible although the mesh can be selected so that post coating it is correct ideally we want the thinnest coating possible to provide a satisfactory barrier. An epoxy coating as suggested would totally fill the aperture of 100 mesh of 0.078mm (although of course a larger pre coated mesh would be selected)
Although exotic material such as mesh in alloy 625 (as was used in the mesh basket case) or CPVC can be selected the ability to supply a coated mesh of small aperture required would be ideal in a large number of industries.
Normally they work with SS316, Duplex where necessary and as mentioned above selected alloys are used, so no their is not specific SS required.
Size of mesh (solids removed) varies from 200 mesh all the way to 5 mesh apertures of (0.07mm to 4mm)
Hope this helps
Sorry if I am still a bit vague the company are not for providing specific applications to help me.

Thanks you again

Robert

[dazarooney]

Robert, I'm not sure if you got the answers you needed in the end but it would be good to know if you did.

[kschewe]

I don't think thermal spray would work for this application. Making the mesh out of exotic metals would be better. Then maybe trying to plate them with nickel or chrome. Trying to spray a mesh would burn up. Maybe using a wire arc system. Making the mesh holes a mill bigger then spraying the mesh to size.

[joncro55]

I know of a company that sells this nickel plated woven wire mesh in various sizes...

http://www.bwire.com/

Have used them in the past to get some wire cloth made of exotic alloys (Hastelloy, Nickel, Silver, Monel, Etc...) and they can usually always get what I am looking for. I am not sure if they make the mesh themselves, or if they already have it in stock, but I am pretty sure they weave mesh here in the United States.