Welding processes and the use of electrodes
Thread Content
For Class D welds of Q3454R plates and 20# steel pipes, as well as Class B welds of 16Mn forgings and 20# steel pipes, is it better to use welding rods of type J507 or J427? If welding is carried out using J507 electrodes, the welding procedure qualification for Q345R can be utilized. However, if J427 electrodes are used, either the welding procedure qualification for Q345R or that for Q245R would have to be applied – in one case the filler metal changes, and in the other case a lower-grade material is used in place of a higher-grade one; neither approach seems appropriate. Solve
Under normal circumstances, it is better to use welding rod 507. It’s not a matter of performance; the main parts of the equipment are made with 507, while using 427 for those areas can lead to confusion and make quality control more difficult.
From the perspective of welding procedure specifications, it is advisable to use weld material J507 for Class D fillet welds of Q345R and 20# steel, while J427 is more suitable for Class B welds of 16MN flanges and 20# pipes. In current welding procedure specifications, welding is generally performed between dissimilar materials, using the lower grade rather than the higher one.