[MW:22803] RE: 22800] Non conform ferrite on Duplex UNS31083

Hello Pedro,

When I'm right connections are made with GTAW root layers. In general you can have problems with corrosion resistance of your weld metal if ferrite content is to low but depends on the environment.

If only root layers are in contact with corrosive medium than this shouldn't be a problem if composition and ferrite content in GTAW weld metal complies with the project requirements.

If also SMAW weld metal is in contact with medium than you can/will have a corrosion issue.

Met vriendelijke groeten / Best Regards,

Herman Pieper

QA-QC Inspector / CSWIP + IWI-C Welding Inspector / IWT / Materials Expert

Job van der Havestraat 6

8384 DB, Wilhelminaoord

Cell: +31 6 51691215

Van: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] Namens Pedro JUNIOR
Verzonden: dinsdag 3 februari 2015 10:34
Aan: materials-welding@googlegroups.com
Onderwerp: [MW:22800] Non conform ferrite on Duplex UNS31083

Dear experts,

Ferrite content has been measured (24 to 29% measured in weld metal) below project requirements (30 to 55%). Counter tests demonstrated same values.

Most of our contractor's WPQRs are qualified with GTAW+SMAW processes for thicknesses over 14 mm.

In order to comply with their general practices, contractor decided to order duplex SMAW filler metal

After review of feedback of the contractor on ferrite content, it appears that ferrite % is quite low in general with SMAW. This feedback has not been clearly figured out on WPQR reports and production welds do not comply with our requirements (client requirements).

Welding monitoring have been done properly. General quality of the weld is good. The concern comes from the filler metal itself.

In case of acceptance.

è Which are the risk of accepting Ferrite Content below the minimal required for duplex?

Best Regards

Pedro JUNIOR QC Piping Inspector TOTAL E&P ANGOLA DT/EPT/MHSAQ/QAQC Tel : +244 222 67 2097 Cell:+244 912 641 681 Email: pedro.junior@total.com
		Mailing Address: TOTAL E&P Angola Rua 6 IL 6 B.I SONILS, Boavista Luanda B.I- 100-Office 011 Luanda - Angola

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