WELDING THEORY - OD1650 - LESSON 1/TASK 1
(2) Field welds are welds not made in a shop or at the place of initial construction and
will be indicated by means of the field weld symbol (figure 4, view D, on page 10).
Extent of Welding Denoted by Symbols.
(1) Symbols apply between abrupt changes in the direction of the welding, or to the
extent of hatching or dimension lines, except when the weld-all-around symbol is used.
(2) The welding on hidden joints may be covered when the welding is the same as that of
the visible joint. The drawing will indicate the presence of hidden members. If the welding on
the hidden joint is different from that of the visible joint, specific information for the welding of
both will be given.
Location of Weld Symbols.
(1) Weld symbols, except resistance spot and resistance seam, will be shown only on the
welding symbol reference line and not on the lines of the drawing.
(2) Resistance spot and resistance seam weld symbols may be placed directly at the
locations of the desired welds (refer to figure 4, view E).
Use of Inch, Degree and Pound Marks. Inch, degree, and pound marks may or may not
be used on welding symbols, as desired, except that inch marks will be used for indicating the
diameter of arc spot, resistance spot and circular projection welds, and the width of arc seam and
resistance seam welds, when such welds are specified by decimal dimensions.
Construction of Symbols.
(1) Fillet, bevel and J groove, flare bevel groove, and corner flange symbols will be
shown with the perpendicular leg always to the left (figure 8, view A, on the following page).
(2) In a bevel or J groove weld symbol, the arrow will point with a definite break toward
the member which is to be chamfered (figure 8, view B). In cases where the member to be
chamfered is obvious, the break in the arrow may be omitted.