Effect of Welding Conditions on the Transverse Distortion in Butt-Welded Joint
Shrinkage Distortion in Welded Joints (Report 3)
1956 Volume 25 Issue 8 Pages 455-460
Details
1956 Volume 25 Issue 8 Pages 455-460
From the results of our previous paper (Report 1), the transverse shrinkage St in butt-welded joint is given by eq. (3), where w is deposited metal per unit weld length (gr/cm), w0 is deposited metal per unit weld length per one pass of weld (gr/cm), W is total deposited metal per unit weld length (gr/cm) (see Fig. 1), h is thickness of plate (cm) and C1 is a constant. C1 is proportional to (I/μα)(1/√φ), where I is welding current (Amp.), u is deposition efficiency of core, α is weight of melted core of electrode per unit current and unit time (gr/A. sec) and is diameter of electrode (mm). Trsnseverse shrinkage of first pass of Sto is given by eq. (5). I/μα depends on the welding conditions and W/h2 depends on the grove of butt-joint.
The result of three series of experiments in Table 1 are plotted on the abscissa of log w. (see Figs. 2-4). Transverse shrinkage curse is decided by the following two factors :
(1) Point of shrinkage of first pass {abscissa log w0
ordinate St0=C0√W/h2∞√I/μa√W/h2
(2)Tangent of St-log w curve =2.302 C1(W/h2)∞(I/μa)(I/√φ)(W/h2)
Transverse shrinkage is decreased by the increase of w0 and by the decrease of 1/μa, 1/√φ and W/h2. (see Figs 5-7).
Angugar change is given by eq. (7) and Fig. 8. It is most affected by the type ob bevel of groove. Angular change is very small when deposited metal of top surface is about 60% of total deposited metal.
