2. Welding Joints, Positions, and Symbols3
Chapter
Welding Joints, Positions, and Symbols

3. Identify the five basic welding joints.
Identify and describe the various welds that may be used in each welding joint.
Label the parts or areas of a grooved butt weld and a fillet weld.
Locate and apply required weld and joint information from an AWS welding symbol.
List and describe the four welding positions.

4. Basic Weld Joints
A welder should understand the type and location of welds needed by reading the welding symbols
A weld joint refers to how the parts are assembled prior to the welding
The item to be joined is base metal or base material

5. Basic Weld Joints There are five types of joints used in welding Butt
Lap
Corner
T-Joint
Edge
(American Welding Society)

6. Butt Joint Butt joints are used when parts are joined edge-to-edge
Edge preparation refers to how the edges are shaped prior to welding
A groove weld is made by fusing molten filler metal into a butt joint

7. Butt Joint The various parts of a groove joint have names Groove face
Groove angle
Bevel angle
Weld root
Root face

8. Butt Joint Various terms are used to describe a completed groove weld
Weld face
Face reinforcement
Weld toe
Root reinforcement
Joint penetration
Weld size

9. Lap and Corner Joints
A lap joint is formed by two overlapping pieces of base metal
A corner joint is formed by placing two pieces of base metal perpendicular or at an angle to one another
Inside corner joints are welded along the inside of the joint
Outside corner joints are welded along the outside edge of the joint

10. T- Joint
A T-joint is formed by two pieces of base metal that are at an angle of approximately 90°
The edges may be prepared as a square, bevel-grooved, J-grooved, or flare-bevel-groove joint

11. Edge Joint and Flange Joint
An edge joint is formed when the surfaces of two pieces are in contact and their edges are even
A flange joint is formed when the edge of one or more pieces is bent to form a flange

12. Flare-Groove Joint
Flare-groove joints are formed when the flanged edges of one or both pieces are placed together to form a single-flare-bevel or a double-flare-groove

13. Types of Welds
A weld is a fused joint between two or more pieces of metal or nonmetal
Fillet welds are made at the intersection of a surface and an edge or in a corner where two surfaces meet
A groove weld is made in a groove or gap between two pieces of metal

14. Types of Welds A fillet weld is made up of three primary dimensions
Weld size
Effective throat
Leg

15. Bead Welds and Weld Passes
A weld bead is one weld pass of filler metal that is added to a weld joint
The first weld pass is the root pass
The second weld pass is the filler pass
The final weld pass is the cover pass
Generally, a weld bead should not be thicker than 1/4″

16. Bead Welds and Weld Passes
Three weld passes are used in this example
The cover pass is a weave bead

17. Stringer Bead and Weave Bead
A weld bead may be a stringer bead or a weave bead
A stringer bead is used when a standard bead width is acceptable
A weave bead is used to create a wider weld pool
The crescent motion is a popular pattern for a weave bead

18. Joint Geometry
Joint geometry is defined as the shape and dimensions of a joint, in cross section, prior to welding
Joint geometry is generally determined by a welding engineer or designer
The joint geometry design should provide space for the welder to reach near the bottom of the weld joint

19. Preparation The edges of thick metal are prepared for welding
Flame cutting
Gouging
Machining
Preparation allows the weld to penetrate as deep as required

20. Joint Alignment The alignment of a joint before
welding is very important
A tack weld is a small weld
used to hold pieces in alignment
Parts may also be held
mechanically using clamps or
other devices
(Bessey Tools North America)

21. Penetration A completed weld joint must be as strong as the base metal
The weld must penetrate deeply into the base metal to be strong
Penetration is the depth of fusion of the weld below the surface

22. Welding Positions Welds may be made in various welding positions
Flat welding position
Horizontal welding position
Vertical welding position
Overhead welding position
Welding positions are determined by the positions of the weld axis and weld face

23. Welding Positions
The weld axis is an imaginary line running lengthwise through the center of a weld

24. The Welding Symbol
Welding symbols are used on drawings of parts and assemblies that are joined together by welding
A complete welding symbol contains all the information about a welded joint
Dimensions may be in SI Metric units or in US Customary units

25. Reference Line, Arrowhead, and Tail
The reference line is always drawn as a horizontal line
The arrow may be drawn from either side of the reference line
The tail is used only when necessary to give additional information

26. Weld Symbols
Weld symbols may be part of the complete welding symbol and indicate the type of weld
(American Welding Society)

27. Arrow Side and Other Side
On the drawing of a weld part, the arrow touches the line to be welded
The side of the metal that the arrow touches is called the arrow side
The opposite surface is called the other side
The arrow side information is always shown below the reference line

28. Root Opening and Grove Angle
The root opening is the space between the pieces at the bottom, or root, of the joint
Prior to welding, the two pieces will be spaced apart the distance indicated by the root opening
The root opening size appears inside the weld symbol

29. Contour and Finish Symbols
The shape of contour of the completed weld bead is shown in the welding symbol
Straight or curved line
Placed between the weld symbol and the finish symbol
If the weld is not to remain in an “as welded” condition, a finish symbol is used

30. Depth of Bevel and Groove Weld Size
The “S” position on the welding symbol
Indicates the depth of the bevel
May indicate the size or strength of welds
May show the size of each leg in a fillet weld
Groove weld size
Is the depth to which the weld penetrates into the base metal
Is given in parentheses in the “E” position on the welding symbol

31. Depth of Bevel and Groove Weld Size
This illustration shows the depth of the edge shape and groove weld size

32. Length and Pitch of Weld
Intermittent welding
Short sections of the weld are spaced across the joint
Used when full strength is not needed
The length dimension indicates the length of each weld
The pitch dimension indicates the distance from the center of one weld to the center of the next weld

33. Length and Pitch of Weld
Intermittent fillet welds may be required on both sides of a joint
With chain intermittent welds, welds begin and end at the same spots
With staggered intermittent welds, the welds are offset
This is shown on the welding symbol by offsetting the fillet weld symbols

34. Length and Pitch of Weld
This illustration shows a staggered weld
Notice the staggered fillet symbols

35. Backing Welds and Melt-Through Symbols
Weld joints that require complete penetration may be welded from both sides
A stringer bead or a cover pass may be all that is required
In such cases, a backing weld symbol is used
The melt-through symbol is used when 100% penetration is required on one-side welds

36. Weld-All-Around and Field Weld Symbols
The weld-all-around symbol indicates that the same type weld joint is to be used on all edges of a box or cylindrical part
When welds are to be
made away from the shop,
a field weld symbol is used

37. Multiple Reference Lines
Two or more reference lines may be used when a sequence of operations is to be done
The reference line nearest the arrow indicates the first operation
The reference line furthest from the arrow indicates the last operation

38. Plug and Slot Welds A plug weld is a weld made in a hole that is round
A slot weld is a weld made in a hole that is not round
The pitch is the center-to-center distance in a series of plug or slot welds

39. Spot Welds
A spot weld is a method of joining two or more pieces together with a weld not at the edge of a part
The spot weld symbol is a small circle
Projection welding is another process used to produce spot welds

40. Spot Welds The following information is given for a spot weld Size
Strength
Spacing
Number of welds
Welding process

41. Seam Welds
A seam weld is another method of joining two or more pieces together
Lap joint
Butt joint
No hole or slot is cut into any parts
The size and strength of the weld are shown to the left of the weld symbol

42. Review of Welding Symbols
This illustration shows examples of various types of welds in various positions

43. Electrode Angles
Two terms are used to describe the electrode angle, or position, in relation to the material being welded
Travel angle
Work angle

44. Travel Angle
The travel angle is measured from a line perpendicular to the weld axis in the plane defined by the weld axis and electrode axis

45. Travel Angle Backhand welding Forehand welding
The top of the electrodes leads the welding end of the electrode
The welding arc is pointing back toward the weld bead
The travel angle is called a drag angle or drag travel angle
Forehand welding
The welding end of the electrode points forward in the direction of travel
The travel angle is called a push angle or push travel angle

46. Work Angle
The work angle is measured from a line perpendicular to the major or nonbutting surface to the plane containing the weld axis and the centerline of the electrode

47. Commonly Used Angles For a butt weld, the work angle is usually zero
For a fillet weld, the work angle is often 45°
Drag or push angles usually range from zero to 40°
A large push angle, up to 85°, is used for gouging