fines remoival; from ground metal surface

...may I guess and suggest etching?

What does the coating manufacturer recommend? I should think an air blast, followed by a tack cloth if the pipe was cleaned before grinding. Use FME practices (foreign material exclusion) for the interior, and rely on flush cycling. Degrease with alcohol or acetone.

BTW; Most coatings reject the residue from non-specific etches.

You could use sand blasting as 'all in one'.

hi, thanks for thought

surface is cleaned by shot blasting, dirt in pores is of metal only,pores are extremely fine just to make slight rough surface but dirt in those pores are not acceptable.

looking for brighter solution

You can also wash the component in Industrial Washing Machine if size is not very big.

Suresh Sharma.

No thanks, it is `1500 mm dia pipes rotating at high speed

how about a magnet?

oilcan13

Magnet will only remove the metal (if magnetic) will leave the grinding wheel material. Additionally if non magnetic, (300 series stainless) will not remove anything. Mechanical removal with wash soap and a stainless steel spiral brush, rinse with water clean with rag then with acetone soaked rag followed with two clean rags. This is the process I use to remove all grindings and contaminates from a stainless steel ingot that we bore a hole in. (48 inches deep 1 Inch in diameter)

yes but pipe in which pores are is also of mild steel.however does one know how to change its strength of magnetic polairty to attract only metallic dust? may be if we generate static electricity and proide negative pole, dust may leave pores?

Your grinding operation is not well defined. Is it a precision surface grind, or a hand held descaling type grind?

For removing scale I have also seen sand blasting used, and on a wire draw machine high pressure water.

The high pressure washer is interesting in that it gave a very clean surface. It can also include chemicals to help prevent future rusting, such as phosphoric acid, or other more complex chemicals.

Here Here GW I concur

So why are you grinding...is your material hard to that you can not mill / turn or are looking for a frictionless surface finish...if this is the case the I would not be sand or shot blasting....what are you trying to achieve in removing this material via the use of grinder?

And what material is it?

If you any additional help www.alnoprodcutservices.com.au

yes, let me explain, it is shot blasted surface of large pipe m.s. say up to 1500 mm dia. surface is prepared for lining but dust in pores are not acceptable

Hello motivepowers,

Firstly, are you going to plate or finish the metal in any 'coating'?

Second, try the sites below for any help to the removal of your particular 'fines'.

http://www.google.com/search?client=safari&rls=en-us&q='fines'+left+on+metal+surface&ie=UTF-8&oe=UTF-8

It would be helpful if you could say what size the area of 'fines' relates to if possible.

Other than that, gradual reduction in the grinding grade, to get finer and finer, or perhaps an 'acid etch' my be the anwer. It really depends on the size and type and shape of the metal you refer to, and, whether you can let the whole piece/s etch or you just want the ground surface only to be treated?

Please keep in touch.

bb

Hi BB( baby bear) nice name huh) let me re explain, it is shot blasted outer surface of large pipe before coating is applied. It cleans surface and for roughness forms pores say up to 60 microns.during blasting, some dust sits inside pores( of course of metal dust only).Before coating, we want this dist to be removed as far as possible, so that coating can be more efficient.

Hello motivepowers,

many thanks for the reply post, and extra detail.

So you need the roughness as a 'key' for the coating. I understand that. Would not compressed air rid the particles, or a vacuum cleaner?

Take care.............

bb

I don't know what's more important cleanness or smoothness?

I only recommended sandblast because I didn't know the environment you're in and maybe stain removal is a higher priority than finish.

If the coating covers minor roughness then sandblast would definitely be your best choice. We used to have that method used on some of our storage tanks to be cleaned all the rusts off on the inside.

I'm curious what those pipes used for and what method you'll end up using out of all the suggestions given!

You could replace shot blasting with wet sand blasting followed by water blast to remove any residual fines.

Water blast after shot blasting will also remove fines.

As mentioned by an earlier poster, water blast can also have various inhibitors and surface treatment chemicals added to prevent subsequent rusting.

If it is not feasible to add inhibitors and the surface must be dried, hot air drying is quick and effective.

What you use is mainly dictated by your particular requirements.

Hello motivepowers,

Just a few remarks............................

Are you sure you are not trying to 'make a silk purse from a sows ear'? Meaning that, often the residual dust can act as a 'key'?

What kind of 'coating' is to be applied. Is it glue to have a layer of lining applied, or is it paint or an 'electrolytic' coating of some kind, which is only a matter of 6/10 microns thick?

Is this a 'one off' or part of a large contract.

Are you doing all the grinding cleaning and, coating?

It seems to me that the 'wet' water ideas could achieve the condition you want?

Has any post been of help to you?

Any chance of a pic'?

bb