RE: [MW:8918] Re: Blasting Profile

RE: [MW:8918] Re: Blasting Profile - SA 2.5

Very easy. Just a piece of self adhesive tape is stuck on to the substrate surface and snatched off, the dust/finings sticks to the tape. By then sticking the tape on to the white paper the dust can easly be seen.

Any dust on a blasted surface will adversly effect the adhesion of a paint film. In condition of low relative humidity, dust and fining passing down a blast hose become electrostatically charged and stick on to the substrate. They must be complately removed from the substrate surface before paint application.

Please note that brushing or air blowing will not remove them. So if any dust presence on the surface the area need to be reblasted.

regards,
Elshan.

> Subject: Re: [MW:8915] Re: Blasting Profile - SA 2.5
> To: materials-welding@googlegroups.com
> From: khalid.descon@gmail.com
> Date: Thu, 23 Dec 2010 17:26:33 +0000
>
> What is the procedure and equipment for dust test if anybody has literature please share.
>
> Sent from my BlackBerry® wireless device
>
> -----Original Message-----
> From: haseeb ph <haseebph@gmail.com>
> Sender: materials-welding@googlegroups.com
> Date: Thu, 23 Dec 2010 07:35:49
> To: Materials & Welding<materials-welding@googlegroups.com>
> Reply-To: materials-welding@googlegroups.com
> Subject: [MW:8912] Re: Blasting Profile - SA 2.5
>
> Dear Vivek,
>
> as everyone said like dust test is nothing to do with blasting
> profile,it is just ensuring that the surface is ok for priming,one
> more thing that you didnt mention the type of abrasive you are
> using,if it is metallic abrasive dust test is not
> required(SSPC)because recylable abrasive will not make dust after
> hitting the substrate but expendable abrasive like copper slag will
> shattered into small pieces after hitting,in this case it is a good
> practice to do the dust test to ensure the quality
>
> I hope it will help you, if anybody have any concern please let me
> know
>
> Thanks & Regards
>
> Haseeb.P.H
>
> On Dec 22, 12:50 pm, Vivek K <vivekk....@gmail.com> wrote:
> > Dear All,
> >
> > If the blasting profile is to be SA 2 1/2, whether dust contamination test
> > is mandatory on the blasted surface.
> >
> > Thanks and Regards
> > K. Vivek
>
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