2. Objectives
• Translate the following seam weld
dimensional information:
– Size of the weld
– Strength of the weld
– Extent of the weld
– Center-to-center spacing
3. Objectives (cont’d.)
• Identify a flush-control symbol
• Distinguish a seam weld on a print
– Not parallel to the joint
– Not parallel to the axis of the weld
4. Seam Welds
• Continuous weld made on or
between overlapping members
• May consist of a single weld or a
series of overlapping spot welds
• Arrow side or other side
significance
• Symbol not used with both side
significance
5. Seam Welds (cont’d.)
• When symbol astride the reference
line
– Arrow side or other side significance
– Weld located between members
• Tail must be used to indicate the
process reference
6.
7. Seam Welds (cont’d.)
• Dimensions applied to seam welds:
– Size
• Expressed in fractions or decimals of an
inch, or millimeters
– Strength
• Shear strength in pounds per linear inch
or Newtons per millimeter
• Newtons expressed with “N”
– Extent
– Center-to-center spacing
8. Seam Welds (cont’d.)
• Dimensions applied on same side
of reference line as weld symbol
• When symbol astride the reference
line, dimensions on either side
• Size of a seam placed to the left of
the symbol
– Indicates width of the weld
9.
10. Seam Welds (cont’d.)
• Strength placed to the left of the
symbol
• Used in place of size when strength
is a required specification
• Length or extent placed to right of
symbol
• When weld extends the full length
of the joint, length not necessary
11.
12.
13.
14. Seam Welds (cont’d.)
• Extent shown when weld extends
less than full length of joint
• Center-to-center distance shown to
right of length dimension
• If length and pitch specified without
detail drawing
– Measured in parallel to axis of joint to
be welded
15.
16.
17.
18.
19. Seam Welds (cont’d.)
• Detail drawing must be used when
intermittent seam weld not parallel
– Reference must be made in tail of
arrow
20.
21. Flush-Contour Symbol
• Indicates the member to be made
flush
• When flat finish required, note
placed in the tail
– Method for postweld finish may also
be indicated
• Not applied to seam-weld symbol
when it is astride the reference line
– Weld between members indicated
22.
23. Multiple-Joint Seam Welds
• One or more pieces inserted
between the two outer members
• Same symbol and elements used
– Regardless of number of pieces
inserted
• Symbol has arrow side or other
side significance only
24.
25. Summary
• Continuous weld made on or
between overlapping members
• Dimensions applied to seam weld:
– Size, strength, extent, center-to-
center spacing
• Flush-contour symbol may be
applied
• Same symbol for multiple-joint
seam welds
