Fig. 2 - Notch toughness is an important factor in the construction of Ships Proper Welding Conditions in Use of DW-IOOE DW-100E offers very little spatter and easy slag removal in uses over a wide range of welding currents as shown in Fig. 3 in all positions including vertical-down position.
Fig. 3 - Proper welding current ranges for all-position welding (DW-100E, 1.2mm^)
Heat input (HI = AXVX60/S where A: welding current, V: arc voltage, and S: carriage speed) is a predominant factor in arc welding in common, affecting quality of welds. Table 3 shows recommended heat input for DW-100E. The minimum heat input is to
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Table 3 - Recommended heat input ranges
In horizontal fillet welding, control of leg length is essential. Welding speed is the governing factor that determines the leg length of a single-pass fillet weld. Fig. 4 shows data of leg length as a function of welding speed in use of DW-100E.
Fig. 4 - Leg length vs. welding speed in use of DW-100E in single pass horizontal fillet welding Weldability of mild steel and 490N/mm2-class high strength steel is quite good. However, cold cracking can occur in the welds when the base metal is a thick section with high carbon equivalent, the weld contains a high amount of diffusible hydrogen, and welding is carried out in a low ambient temperature. Diffusible hydrogen content of DW-100E weld metal is as low as the ship- class requirement of Grade H10, however, 30-150øC of preheating is needed depending on atmospheric temperature and plate thickness. |