1.This round bead, it's a successful weld.
2.Narrow and fall bead.This is caused by too much pressure during welding.
3.Too small bead. Pressure is not enough while welding.
4.There is a noticeable gap between the welding beads, either because the welding temperature has not been reached or the change-over time has been too long and the end of the pipe has cooled down.
5.High & low bead. Different heating time or fusion temperature causes that.
6.This occurs because the pipes are not aligned during welding and deviate by more than 10 per cent of the wall thickness.
Once the user has a good understanding of the welded pipe, the welding beads can be used to check for problems arising from the welding and to correct them.