Weld joint preparation.pdf

Based on weld joint

1. Weld Joint Preparation
(ISO 9692)

2. Edge Preparation -Need
Poor penetration
Poor strength
Good penetration Good strength
(100% joint
efficiency)

3. Edge Preparation
Factors which influence choice of edge preparation
-Thickness
-Material
-Welding process
-Extent of penetration required
-Welding distortion
-Cost

4. Basic Joint Types
butt
tee
lap
corner
edge

5. Basic Weld Types
Groove welds Fillet weld
Plug / slot weld
Spot / seam weld

6. Applicable Welds for Butt joint
Square Groove weld
V Groove weld
U Groove weld
Bevel Groove weld
J Groove weld

7. Applicable Welds for Butt joint
Double V Groove weld
Double U Groove weld
Double Bevel Groove weld
Double J Groove weld

8. Applicable Welds for Tee joint

9. Applicable Welds for Lap joint Plug / slot weld
Spot / seam weld
Fillet weld

10. Applicable Welds for Corner Joint

11. Applicable Welds for Edge Joint
Edge weld

12. Butt joint
Square Groove weld
Root gap

13. Butt joint
Single V Groove weld
Groove angle α
Root face
Root gap

14. Weld Reinforcement
Correct
reinforcement
Minimum cost
Good joint
strength
Excess reinforcement
High cost
Poor joint strength
Under
reinforcement
Poor joint strength

15. Butt joint –Complete Joint penetration
Weld from face side
Back gouging
Back weld

16. Butt joint –Complete Joint penetration
Backing weld
Back gouging

17. Butt joint –Complete Joint penetration
(welding from one side)
TIG / SMAW
welding
Consumable
guide

18. Butt Joint –Double V groove
Less weld metal
Less distortion
Higher edge preparation cost
Better for thickness > 20 mm
More weld metal More distortion
Lower edge preparation cost
Better for thickness < 20 mm
Double V groove
Single V groove

19. Butt Joint –U groove
Good access at the root
Less weld metal
Higher edge preparation cost
Better for thickness > 40 mm
Groove angle
Root face
Root gap
Root radius

20. Butt Joint –Bevel groove
Double bevel groove
Single bevel groove
Bevel angle 40 to 50°
Difficult to approach
the root
Weld defects
Back gouging to
remove root defects
Good weld quality

21. Butt Joint –J groove
Good access at the root
Back gouging and back welding to get good weld quality
Less weld metal
Higher edge preparation cost
Better for thickness > 40 mm

22. Tee Joint –Full strength joint
leg
leg
throat
throat = 0.707 x leg
leg = 1.414 x throat
In a full strength
joint, leg = 0.75 x
thickness

23. Tee Joint –Full penetration joint leg = throat
leg = throat
45°or 60°

24. Tee Joint
Theoretical throat
Actual throat
AWS D 1.1 recommendation when gap > 1.6 mm –
to increase leg size of fillet by the amount of gap

25. Lap Joint
AWS D 1.1 recommendation
Overlap = 5 x thickness (1 inch minimum)
Gap between mating faces = 1.6 mm max
overlap

26. Welding Position –Groove
1 G
2 G
3 G
4 G

27. Welding Position –Groove
1 G 2 G
5 G 6 G
45°

28. Welding Position –Fillet
1F
2F
3F
4F

29. Welding Position –Fillet
1F
2F
5F

30. Welding Positions –Groove
Position Inclination of axis Rotation of face
Flat 0°to 15° 150°to 210°
Horizontal 0°to 15° 80°to 150°
210°to 280°
Overhead 0°to 80° 0°to 80°
280°to 360°
Vertical 15°to 80° 80°to 280°
80°to 90° 0°to 360°

31. Welding Positions –Fillet
Position Inclination of axis Rotation of face
Flat 0°to 15° 150°to 210°
Horizontal 0°to 15° 125°to 150°
210°to 235°
Overhead 0°to 80° 0°to 125°
235°to 360°
Vertical 15°to 80° 125°to 235°
80°to 90° 0°to 360°

32. Joint preparation
According to ISO 9692
Weldingandalliedprocesses-Recommendationsforjointpreparation
Part1:Manualmetal-arcwelding, gasshieldedmetal-arcwelding, gas
welding, TIG weldingandbeamweldingofsteels