Welding Galvanized Structural Steel

The weld strength should be the same whether welding galvanized steel or not.

Welding galvanized structural steel. The galvanized steel is removed and allowed to cool. Thus for galvanized structural fabrications the zinc coating should be removed at least 1 4 2 5 10 cm. Welding thick galvanized coatings or butt welds or welding creases or corners where the galvanization naturally builds up benefits from grinding the galvanization off first. Aws d 19 0 calls for welds of galvanized steel on areas free of zinc.

The challenge is welding over the zinc coating. Galvanized parts are used in a wide variety of industries including automotive structural steel construction oil field and many more. Arc welding requires striking a low voltage high current arc between an electrode and the workpiece base metal. While it is typically a good idea to complete any welding or fabrication before galvanizing the steel which will result in a more corrosion resistant finished product under some circumstances steel must be welded after.

Hot dipped galvanized steel is dipped into a vat of molten zinc which coats the steel. Welding galvanized steel has gotten a bad reputation over the years rightfully so as the fumes produced during welding can be incredibly dangerous to the welder s health. Galvanized steel welds similar to uncoated carbon steel when properly prepped. All commonly prac ticed welding and cutting techniques gas metal arc shielded metal arc man ual metal arc oxyacetylene friction re sistance can be used on galvanized steel see american welding society s.

Tions for welding galvanized steel as for galvanizing welded steel must be integrated into the overall structural fabrication design. Take the proper safety precautions by wearing a welding mask a good welding respirator gloves and an apron. Preparation of base metal and welding techniques for sheet plate and structural steel are the same as for welding ungalvanized steel. Welding on galvanized steel can be necessary if the final structure is too large to be dipped in a galvanizing bath or for structures that must be welded in the field.

Structural shapes such as angles channels are frequently hot dipped. The intense heat generated with this arc melts the base metal and allows the joining of two components. It is a great process to prevent corrosion. Techniques for avoiding entrapment of zinc as discussed in sections 6 1 and 6 2 shall be employed.

As long as the zinc oxide gets access to air to burn off. Structural steel welding semih genculu p e.