Weld Procedure for 425C11 stainless steel

Author: Dr. Bob Cattley

Applicability

Weld procedure for repair of casting defects and corrosion resisting overlay to ASME IX for material group P6, 12% Chromium Martensitic stainless steels.

Procedure

Remove all traces of grease and moisture.

Clean and grind the defective area and remove all traces of cracking.

Inspect the area to be repaired by magnetic particle or dye penetrant method for cracks.

Ensure all traces of cracks and traces of penetrant are removed before proceeding.

Pre heat 100 – 150°C.

Weld defect by the TIG process

1              Shield gas argon
2              Flow rate 8 – 12 litres per minute
3              Tungsten electrode, φ 3.25 mm WT 20
4              Power source DC
5              Tungsten electrode negative
6              Current 150 – 250 Amps
7              Filler rod matching composition to the parent metal.
8    Inter-pass temperature 100 – 200° C
9             Grind clean the edge of the weld to remove oxides before depositing the next run

Grind or machine the repair down to the finished profile and inspect for cracking using magnetic particle or dye penetrant techniques.

Post weld heat treatment:

1                                Heat slowly to 600 – 620°C
2                                Hold for 1 hour
3                                Cool in still air