Definition
Welding joins two or more metal parts by melting and fusing them, usually as an assembly step after individual parts are machined or formed.
What it means for the calculation
Joint preparation and the heat-affected zone determine lead time and post-processing; welding is rarely a standalone drawing line, usually an assembly step.
Where it appears on the drawing
Shown with a weld symbol on a leader line indicating joint type, size and sometimes finish, usually on an assembly drawing rather than a single-part drawing.
Common mistakes
Treating a weld callout as a single quick operation without accounting for fixturing, distortion control or post-weld machining and inspection. Also overlooking that heat can distort a nearby tight tolerance.
Joint preparation and the heat-affected zone determine lead time and post-processing; welding is rarely a standalone drawing line, usually an assembly step.
See how Blake reviews a partFrequently asked questions
Is welding usually shown on the same drawing as a machined part?
Often not; it typically appears on a separate assembly drawing that references the individual part drawings.
Why can welding affect a nearby tight tolerance?
Because the heat-affected zone can distort the material, sometimes requiring a post-weld machining pass to restore tolerance.
What is a weld symbol?
A standardized leader-line symbol that specifies weld type, size and location without spelling it out in a sentence.