What are the principal parts of V-and U-groove joint preparations?
•Depth of bevel
•Size of root face
•Root opening
•Groove angle
•Bevel angle
See Figure 4–3.
Figure 4–3Parts of V- and U-groove joint preparations
Edge Shape Combinations
What are the most common combinations of joint preparations for butt joints?
See Figure 4–4.
Figure 4–4Single-groove and double-groove weld joint
What common preparations are used on corner joints?
See Figure 4–5.
Figure 4–5Weld preparation for corner joints
What weld preparations are used on T-joints?
See Figure 4–6.
Figure 4–6Weld preparations for T-joints
What are the weld preparations for edge joints?
See Figure 4–7.
Figure 4–7Weld preparations for edge joints
What are the weld preparations for lap joints?
See Figure 4–8.
Figure 4–8Weld preparations for lap joints
Selection of Joint Preparation
What determines which joint preparation geometry to use?
The factors are:
•Kind of joint loads (tension, compression, shear, or torsion).
•Level of joint loading.
•Static or dynamic loading.
•Thickness and type of the metals joined.
•Welding position.
•One side/both sides access to the weld.
•Skills of welders.
•Trade-offs between joint preparation costs/filler metal costs/welding labor costs; each joint and geometry carries its own combination of total cost.
What is an excellent source of weld joint design and preparation information for steel?
The Structural Welding Code—Steel, ANSI/AWS D 1.1 is a document with over 50 detailed drawings for pre-qualified joint designs using SMAW, GMAW, and FCAW for steel plate. Joints for submerged arc welding (SAW) are also included. There is additional information for joining tubing, weld testing, and inspection. The document is available from the AWS.
Joint Preparation
What are the most common weld preparations?
See Figure 4–9.
Figure 4–9A few typical weld preparations
Parts of the Weld
What are the terms used to describe the parts of a groove weld?
•Effective throat or size of weld
•Face
•Toe
•Face Reinforcement
•Root Reinforcement
See Figure 4–10.
Figure 4–10Parts of a groove weld
What are the terms used to describe the parts of a fillet weld?
•Leg or size of weld
•Face
•Toe
•Convexity
•Root penetration
•Fusion zone
•Leg of a fillet weld
•Root of the weld
•Actual throat and theoretical throat
See Figure 4–11.
CONVEX FILLET WELD
Figure 4–11AParts of a convex fillet weld
CONCAVE FILLET WELD
Figure 4–11BParts of a concave fillet weld
Welding Positions
How are welding positions plate designated?
They are divided by the position of the axis of the weld with respect to the horizontal and whether they are made on plate or pipe. They are used to designate positions for testing of welders and the application of a specific process. See Figure 4–12.
Figure 4–12Groove weld (upper) and fillet weld positions (lower)
What are the welding positions for pipe?
See Figure 4–13. Note the difference between welding positions A , and C: In position A, (1G) the pipe may be rotated about its longitudinal axis to provide access to any part of the weld joint allowing the welder the opportunity to weld the entire pipe in the flat (1G) position; in position C, (5G) the pipe is fixed and cannot rotate forcing the welder to weld upward or downward vertically, flat on the top and overhead on the bottom; position