Simplification of weld joint geometry

When using Fig. 5.2-5.15 it is therefore necessary to decide whether the welded joint under consideration is best simulated by plate or cylinder geometry. 

Fillet welds are thus best simulated by cylindrical geometry. Certain configurations do not fit this simple subdivision T butt, cruciform butt and corner butt welds, for example, are best considered as fillets simulated by cylindrical geometry. No rigid subdivisions can be made in such cases and each problem must be considered individually taking into account material thickness. 

Roberts and Wells have shown that in a single-pass weld with a characteristic of between 0.25 and 1.0, the thermal cycle approxi- 

25 and 1.0 cover the majority of welding conditions, so that this criterion may be used to determine the plate widths for which the infinite plate assumption is applicable to partial penetration butt welds. 

Rectangular slabs whose width and length each exceed three times the thickness can also be considered as infinite plates. The plane plate simplification can thus be extended to fully penetrating butt welds using this criterion. 

---