Cautions for tank welding

Welding of storage tanks

1. Welding process evaluation

For the first use of steel, according to the steel number, plate thickness, welding methods and welding materials, according to the current national standards and provisions of the process evaluation, to determine the appropriate welding process. Butt weld specimens and T-shaped fillet weld specimens were used for welding process evaluation, among which the butt weld specimens were subjected to tensile test and transverse bending test.

2, welder requirements

For ordinary welders engaged in electrode arc welding, submerged arc welding and gas electric vertical welding, usually according to GB50236-1998 assessment; Welders who have passed the examination according to the detailed rules for the examination of welding operators of special equipment and have obtained the certificates of steel class, group and specimen classification code issued by the quality and technical supervision departments may engage in the welding of storage tanks without having to take the examination again.

3. Preparation before welding

In order to ensure welding quality, welding equipment should meet the requirements of tank welding construction. For tank wall butt welds with tensile strength σb≥430MPa and plate thickness ≥13mm, low hydrogen welding electrode should be used. Before welding, the welding material should be dried and used according to the product specification or the provisions of Figure 1. After drying, the low hydrogen electrode should be stored in the insulation cylinder of 100℃ ~ 150℃, and be taken with use. It is worth mentioning that the sealed flux-cored wire and the flux-cored wire in the sealed box are no longer dried in principle, and the flux-cored wire should be cooled to room temperature after drying before use.