Page 127 - CITS - Welder - Trade Practical

WELDER - CITS

Skill Sequence

(ELBOW) Joint on MS pipe ø50×3mm wall thickness in

flat position

Objectives: At the end of this exercise you shall be able to
• prepare and weld (ELBOW) joint on MS pipe ø50×3mm wall thickness in flat position.

nozzle to the blowpipe to help in fusing both the edges of the joint (which is 3mm thick) to the full depth and get
good root penetration.

Also, the joint which is elliptical in shape can be welded properly with good fusion and root penetration only if the
tack welded pipes are welded in 4 segments.
The segments are divided on the tacked pipe elbow joint as shown in Fig 2 under job sequence.

This division into 4 segments will help to keep the job in the required position so that the welding is done partially
by vertical welding technique and partially by flat position.
In addition, the distortion in the pipe joint due to welding can be controlled by welding the segment in the sequence
1,3,2 and 4.
Maintaining a continuous keyhole as done in pipe square butt joint will help in getting good root penetration.
During welding fuse, the tacks fully and also ensure proper fusion of edges and root of the joint of each segment.
Use the blow pipe and filler rod angles of 60 - 70° and 30 - 40° to the tangent at the point of welding. Give a very
slight side to side motion to the blowpipe.

Pipe welding ‘T’ joint on MS pipe ø50mm and 3mm
wall thickness in flat position (OAW)

Objectives: At the end of this exercise, you shall be able to
• draw the development for 90° T branch
• cut and prepare the pipes as per dimensions
• set 90° angle of the branch pipe using try square
• tack weld the pipe and recheck the angle
• start and complete the weld in two halves
• manipulate the blowpipe and filler rod holding them at the required angles during welding
• clean and inspect for external weld defects.

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CITS : C G & M - Welder - Exercise 25