SOME INVESTIGATIONS IN STRENGTH CHARACTERISTICS OF FILLET WELDS

Abstract

The present investigation has been carried out to determine the influence Of heat input-on the strength of the fillet welds of low carbon structural steels. The investigation reveals that a minimum-heat input of the order of 850 J/mm is needed to provide safe cooling, rate to prevent martensitic structure in HAZ. However, to get adequate root penetration, the minimum heat input varies with the size of the electrode selected. The minimum heat input for various size of electrodes is given as below. Size of Electrode Heat Input (mm) (J/mm) 3.15 900 4.0 1000 5.0 1350 Further it was observed-.that for this type of steel, it is desirable to build a single layer root weld of larger leg length with higher heat input as compared to build the'.same size leg length using two or three passes of low heat