smart143
Mechanical
- Feb 3, 2012
- 78
My welder has welded a PQR cupon of Duplex (UNS S31803) on 30 mm thick plate by GTAW +SMAW process, the electrode used was of E2209-15 having Ferrite value as 36 in MTC.
Heat input used during welding was from 0.80-1.00kJ/mm. I did not checked the ferrite in as welded condition. Cupon was subsequently solution annealed at 1060 deg C for 75 mins.
Now test lab reports ferrite in weld as 25% whereas ferrite in HAZ is 51% & in PM is 59%.
NACE MR 0175 compliance is required so though all ASME sec IX test are passed the cupon is failed as ferrite in not meeeting the requirement of 35-65.
Can some body guide me where I went wrong & what shall I do now. I know that ferrite in austenitic tends to reduce post solution annealing,does same phenomenon occures in Duplex also. I did not checked ferrte before soutional annealing.
Heat input used during welding was from 0.80-1.00kJ/mm. I did not checked the ferrite in as welded condition. Cupon was subsequently solution annealed at 1060 deg C for 75 mins.
Now test lab reports ferrite in weld as 25% whereas ferrite in HAZ is 51% & in PM is 59%.
NACE MR 0175 compliance is required so though all ASME sec IX test are passed the cupon is failed as ferrite in not meeeting the requirement of 35-65.
Can some body guide me where I went wrong & what shall I do now. I know that ferrite in austenitic tends to reduce post solution annealing,does same phenomenon occures in Duplex also. I did not checked ferrte before soutional annealing.
