Page 146 - CITS - Welder - Trade Theory

WELDER - CITS

Welding symbols as per BIS & AWS. Reading

of assembly drawing

Objectives ; At the end of this lesson you shall be able to
• describe the welding elementary symbols
• explain the reference line, arrow-head
• explain the welding symbols.

Necessity: For conveying the information required for welding for designers and welders, standard symbols are
used. The symbols described below provide the means of placing on drawing the information concerning type,
size, location of weldment.
Elementary symbols (As per IS 813 - 1986): The various categories of welds are characterized by a symbol
which in general is similar to the shape of the weld to be made. (Table 1)
Supplementary symbols: Elementary symbols may be complemented by another set of symbols (supplementary)
characterizing the shape of the external surface of the weld. Supplementary symbols on elementary symbols
indicate the type of weld surface required.
TABLE 1
Elementary symbols

SI.No Designation Illustration Symbol No

1 Butt weld between plates with raised
edges (the raised edges being melted
down completely)

2 Square butt weld

3 Single V butt weld

4 Single bevel butt weld

5 Single V butt weld with broad root face

6 Single bevel butt weld with broad root
face

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CITS : C G & M - Welder - Lesson 33 - 43 CITS : C G & M - Welder - Lesson 33 - 43