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[MW:2925] Re: SS 410

By Materials & Welding
why not pickling & passivation after PWHT?

Use K-2 paste , u may also try chemicals from Avestapolarit (use as recommended by respective manufacturer data sheet)

On Tue, Aug 11, 2009 at 1:34 PM, Amarjit Singh <amritas2001@gmail.com> wrote:

Hi,

Can anybody guide for the following
1) In case of SS 410 Cald vessels, pickling & passivation is required
to be done after fabrication. But as the components are stress
relieved after clad restoration the surface of 410 weld are & clad
also does not get cleaned properly after pickling.
2) The pickling is generally carried out as per ASTM A380
3) Is there any better pickling agent which can give better surface
after pickling ? What is the ratio if it is a mixture? What is the
time & temperature of application.

regards,
Amarjit singh
0091-9867506448




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