WELDING THEORY - OD1650 - LESSON 1/TASK 1
(3) Multiple Joint Flange Welds. For flange welds in which one or more pieces are
inserted between the two outer pieces, the same symbol as for the two outer pieces will be used
regardless of the number of pieces inserted.
Resistance Spot Welds.
(1) General. Resistance spot weld symbols (refer to figure 3, view B, on page 9) have no
arrow or other side significance in themselves, although supplementary symbols used in
conjunction with them may have such significance. Resistance spot weld symbols will be
centered on the reference line. Dimensions may be shown on either side of the reference line.
(2) Size of Resistance Spot Welds. Resistance spot welds will be dimensioned, by either
size or strength, as follows:
(a) The size of resistance spot welds will be designated as the diameter of the weld
expressed in fractions or decimally in hundredths of an inch, and will be shown, with or without
inch marks, to the left of the weld symbol (figure 15, view A, on the following page).
(b) The strength of resistance spot welds will be designated as the minimum
acceptable shear strength in pounds per spot, and will be shown to the left of the weld symbol
(figure 15, view B).
(3) Spacing of Resistance Spot Welds.
(a) The pitch of resistance spot welds will be shown to the right of the weld symbol
(figure 15, view C).
(b) When the symbols are shown directly on the drawing, the spacing will be shown
by using dimension lines.
(c) When resistance spot welding extends less than the distance between abrupt
changes in the direction of the welding, or less than the full length of the joint, the extent will be
dimensioned (figure 15, view D).