Page 131 - CITS - Welder - Trade Theory

WELDER - CITS

The techniques used for the positional welding of plates are also applied when welding pipes.
For thin walled pipes up to 5 mm, the leftward technique is used in any position. (Fig 2)
The leftward, rightward or all-position rightward techniques are used as appropriate on sections of 5 mm and
above. (Fig 3)

Fig 2

Fig 3

Differences between plate welding and pipe welding:
In the plate welding the total welding line can be seen at any time. In pipe welding only a portion of the welding
line can be seen at any time.
In plate welding, the line of weld is in only one position. In pipe welding, welding can be done in one position
when it can be rotated. (Fig 4) Otherwise all-position welding can be done in the pipe when the pipe is in fixed
position. (Fig 6) Sometimes the pipe may be in a fixed position and only one position of welding will be done. E.g.
2G Position. (Fig 5)

Fig 4

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