To improve the welding quality of the locally drying underwater SMAW

develops a new device in the locally drying underwater SMAW and carry out a lot of systematic technology experiments. By the experiments

we finally get such results:the structure of the device is simple

the welding formation is well. Compared to the drying welding

the penetration improves a lot in the welding and the weld width decreases a little under the water

because of compression of the arc by gas. With the increase of water depth

the gas pressure increases accordingly

the penetration improves and the weld width decreases further. In addition the transition between weld and base metal is more smooth

and this reduced stress concentration.