1. 1
IMPORTANT CODE REQUIREMENT AND
PRACTICES RELATED TO WELDING
2. Checkthe seamnumberon the job.
( A ) BEFORE STARTING WELDING
1. Forspecific seam:
Refershop weld plan, WPS and test plan.

2. 2
( A ) BEFORE STARTING WELDING
6. Checkcable connections and earthing.
IMPORTANT CODE REQUIREMENT AND
PRACTICES RELATED TO WELDING
8. Provide run - in, run - out plates forL - seams.
25 mm 25 mm
25 mm25 mm
7. Clean WEP+25 mmon eitherside. Remove rust , paint, oil etc.

3. 3
11. Use SS wire brush /wire wheel forSS, Inconels , Monels and
Cupro-nickels. Do not use grinding wheels used on CS.
9. Get temperature sticks for preheat & interpass.
Temperature > Preheat
< Interpass
25 mm 25 mm
BURNER
10. Checkpreheat at least 25 mm
away fromWEPon both sides.
IMPORTANT CODE REQUIREMENT AND
PRACTICES RELATED TO WELDING

4. 4
IMPORTANT CODE REQUIREMENT AND
PRACTICES RELATED TO WELDING
2. Weaving < 3 x Electrode diameter.
( B) WHILE WELDING
1. Tacks and temporary cleats
- Use specified electrodes and preheats
- Qualified Welder
- No hammering
4. SMAWElectrode left overafter4 hrs - return to stores.
3. No stray arcing on job.

5. 7
• WELD JOINT NOT CLEAN
• LOWER PREHEAT TEMPERATURE
WELDING DEFECTS
POROSITIES:
• STRONG WIND FLOW ON ARC

6. 8
- GTAW / GMAW / FCAW :
• RUSTED FILLER WIRE
• DAMAGED TORCH- CLOGGED TUBE, GAS PASSAGE
• TURBULENT GAS FLOW - USE GAS LENS
• INADEQUATE GAS FLOW - FAULTY FLOW METER
• FCAW GAS PREHEATER NOT WORKING
• GAS PURITY CHECK
WELDING DEFECTS
POROSITIES:

7. 9
• IMPROPER INTERPASS CLEANING
• POOR BEAD FINISH- ROUGH, LUMPY BEADS NOT
DRESSED BEFORE WELDING
• FAULTY RESTART - LUMP AT STARING POINT - TO BE
GROUND
• WELDING PARAMETERS (I,V, T.S) NOT AS PER WPS
• WRONG BEAD PLACEMENT
SLAG INCLUSIONS:
WELDING DEFECTS

8. 10
• LOWER CURRENT
WELDING DEFECTS
LACK OF FUSION / PENETRATION
LF
LP
• POOR WEP / SET-UP - LOW ROOT GAP,
HIGH ROOT FACE, LOWER INCLUDED ANGLE
• RUST / PAINT ON WEP

9. 11
• UNBAKED ELECTRODES / FLUXES
• LOW PREHEAT
• INSUFFICIENT POST HEATING
• UNCLEAN WELD JOINTS
WELDING DEFECTS
CRACKS

10. 12
• HEAVY RESTRAINT- WELD TACKS WITH HIGHER
CROSS SECTION
• EXCESSIVE LOCAL HEATING - USE OF RING BURNERS
( NOZZLE# SHELL/ D.END JOINTS )
• USE OF WRONG ELECTRODE / FLUX
• FAULTY CONS. QUALITY / SELECTION
WELDING DEFECTS
CRACKS