In many organisations, the design engineer expected to provide welding procedure sheets alongwith his designs. For this purpose he takes help from the welding engineering and the shop supervisor. To be a good designer he should have the knowledge of welding technology (welding processes, procedures and weldability of metals. He is advised to study this entire book.

5

16K

Fig. 8.7 Size of fillet welds

8.2.1 Steps in Preparing Welding Procedure Sheets

1. Plate preparation. This includes plate cutting and edge preparation. Plate cutting could be done by using:

Punch press blanking Nibbling

Cut-off on Lathe (bars/tubes)

Edge preparation could be done by using:

Flame cutting torch; for single-V single tip, for double-V multiple tip torch is pre-

ferred.

Edge planer is most suitable for U and J preparation.

Flame or arc guaging or chipping for back-pass.

2. Plate forming. Forming is the next step. Common forming methods include:

— Flanging and dishing

— Press die forming and drawing.

3. Jigs, fixtures, positioners and clamps. A designer may be called upon to design jigs, clamping systems and fixtures to assemble parts quickly and accurately for welding. With­out a good fit-up a quality welded product is not possible. Toggle clamps, cam clamps and hydraulic clamps are used to clamp the parts before welding. Magnetic clamps could also be used for instance in fixing a stiffener to a flat plate.