Welded Joints 171
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5. The arrow of the symbol must point towards the joint which requires welding (Fig. 11.6).
6. When only one member is to be edge prepared to make the joint, the arrow should point
at that plate (Fig. 11.7).
7. Dimensions of size are indicated in mm without writting the unit mm. The letter a or z
is placed in front of the value of the fillet size, depending upon whether the throat or leg
and length of the weld is shown on the right hand side. If no length is given, it implies
that full length is to be welded (Table 11.5).
8. If unequal legs of fillet are to be used, they should also be given on the left hand side.
9. If a weld is to be made all around a joint, a circle should be placed at the elbow, connecting
the arrow to the reference line (Fig. 11.4 a).
10. If a weld is required to be made on the site or during erection or assembly, it is represented
by a filled-in circle at the elbow, connecting the arrow and the reference line (Fig. 11.4a)
11. If a weld is to have a flush or flat finish, a straight line should be added above the
symbol.
12. The welding process is indicated, if required, at the end of the arrow (Fig. 11.4 b).
11.7 Welding Process Designations (Abbreviations)
In special cases, the technique of welding is indicated along with the welding symbol as a
convention. To avoid lengthy notes, the abbreviations (Table 11.6) are written as a note. In
some cases, code number is given with a foot note on the drawing near the title block.
11.8 Examples
The assembly drawing of a shaft support fabricated by welding is shown in Fig. 11.13 c, using
the conventional weld symbols.
The drawing of the individual components (part drawings) with edge preparation
wherever necessary, before they are joined by welding, are shown in Fig. 11.13 a. The isometric
view of the assembly is shown in Fig. 11.13 b.
Table 11.6 Welding process designations
Designation Welding process Designation Welding process
CAW Carbon arc welding IB Induction brazing
CW Cold welding IRB Infra red brazing
DB Dip brazing OAW Oxy-acetylene welding
DFW Diffusion welding OHW Oxy-hydrogen welding
EBW Electron beam welding PGW Pressure gas welding
ESW Electro slag welding RB Resistance brazing
EXW Explosion welding RPW Projection welding
FB Furnace brazing RSEW Resistance seam welding
FOW Forge welding RSW Resistance spot welding
FRW Friction welding RW Resistance welding
FW Flash welding SAW Submerged arc welding
GMAW Gas metal arc welding TB Torch brazing
GTAW Gas tungsten arc welding UW Upset welding
