Re: [MW:6784] Re: Polarity qualification?

Hi,

As per QW353 for SMAW,Change in polarity is not an essential variable.He can weld with both.

But as per QW356 for GTAW, change in polarity is an essential variable.So if the welder qualified with DCEP,he can weld only with DCEP.If you want to use him to weld with DCEN,then he have to qualify again with DCEN.

Thanks & Regards,

(karthik)

Karthikeyan.S

QA/QC Manager

Getabec Energy Co.,Ltd.

379,Moo6,Soi8,Nikhomphatana,

Rayong-21180,

Thailand.

Phone: 0066 38 897035-8 (Off)

Fax: 0066 38 897034

Hand Phone: 0066 892512282

--- On Sun, 8/29/10, Engineer Mech <mengineer010@gmail.com> wrote:

From: Engineer Mech <mengineer010@gmail.com>
Subject: [MW:6759] Re: Polarity qualification?
To: "Materials & Welding" <materials-welding@googlegroups.com>
Date: Sunday, August 29, 2010, 2:25 PM

Hi,

in 409.4, tat given as change in polarity?
For ex, My job is to be done with E 7016 DCEN, & E7018 DCEP.
i have qualified welder wit DCEP.
Is he qualifies to weld wit DCEN or not? Either in supplementary
essential or non essential.. how it will be?
pl explain........

On Aug 28, 3:28 pm, "PREM SHANKARDUTT NAUTIYAL"
<prem_nauti...@rediffmail.com> wrote:
> Hi
>
> If you refer ASME Sec IX, QW-253 table, which talks about the welding variables procedure specifications for SMAW, then refer QW-409.4 (electrical characteristics), which mentions that a change in current or polarity is Supplementary essential variable for Impact requirements and Non-Essential variable for Non-impact requirements.
> What is your case?
>
> Regards
>
> Prem Nautiyal
>
> On Sat, 28 Aug 2010 15:26:12 +0530 wrote
>
> >Dear all
>
> If one qualifies in DCEP for SMAW,
>
> Whats the range qualified for those either DCEP only or both (DCEP&
>
> DCEN)?
>
> any limits given in specs? where?
>
> Thanks
>
> --
>
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>
> PREM S NAUTIYAL
> CELL : 9820313278

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