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 B is pipe in a vertical position and welded on the horizontal plane; pipe in D is on a 45° angle and all positions (flat, horizontal, vertical and overhead) are welded when pipe is in this position; the final position is pipe at a 45° with a restrictor in place (the restrictor allows the welder to weld only from one side of the restrictor) making this the most difficult of all welding positions.
Figure 4–13Pipe weld positions
Plug and Slot Welds
What are plug and slot welds and why are they used?
They join two (or more) parts together by welding them at a point other than their edges. Plug and slot welds are used to secure multilevel parking garage and ship decks from shearing forces. They are particularly useful in sheet metal and auto-body work where welds can be completely concealed by grinding and painting. A hole or slot is made in the work-piece facing the welder and weld is made inside the hole. Filler metal completely fills the hole or slot and penetrates into the lower work-piece(s) securing them together. Plug welds are round and slot welds are elongated and rounded at the ends.
See Figure 4–14.
Figure 4–14Examples of plug and slot welds
Intermittent Welds
What is the difference between a chain intermittent and a staggered intermittent weld?
See Figure 4–15.
Figure 4–15Chain intermittent fillet weld (left) and staggered intermittent fillet weld (right)
Welding Terminology
What terms describe the position of the electrode with respect to the weld?
They are:
•Axis of the weld—an imaginary line drawn parallel to the weld bead through the center of the weld.
•Travel angle—is the smallest angle formed between the electrode and the axis of the weld.
•Work angle—for a T-joint or corner joint, the smallest angle formed by a plane, defined by the electrode (wire) and the axis of the weld, and the work piece.
•Push angle during forehand welding—this is the travel angle during push welding when the electrode (wire) is pointing toward the direction of weld progression.
•Drag angle during backhand welding—this is the travel angle during drag welding when the when the electrode (wire) is pointing away from the direction of weld progression. See Figure 4–16.
Figure 4–16Orientation of the electrode
What is travel speed?
It is the velocity or speed of the electrode (wire) along the travel axis, usually in inches/minute or cm/minute.
What is a tack weld?
Welders place small, initial welds along joints to hold the work pieces in place so the parts remain in alignment when they are welded. Tack welds work hold work firmly in position, but can be broken with a cold chisel
