Page 190 of 561

ALBRONZE-344

Unitor ALBRONZE-344 is a bronze electrode made specially for joining and cladding of bronze alloys as well as for joining these metals to steel and cast iron. It is also used for welding gliding surface overlays on steel.

Unitor ALBRONZE-344 is not recommended for welding Yorcalbro and Cunifer pipes.

The welded deposit has high strength properties and good resistance against cavitational wear and corrosion in seawater. The deposit has low coefficient of friction and excellent weldability.

Applications include ships’ propellers, pumps, pump parts, bearing shells, condensers, valves and turbine blades.

Clean the welding area thoroughly and remove all oxidation. Machine or grind off fatigued metal. Make a suitable welding groove using a 60–90° angle. The groove can be formed by grinding. Pre-heating is normally not required but it may be necessary to pre-heat large workpieces up to 150°C. The temperature must not exceed 200°C during welding. When surfacing steel parts, AC or DC positive polarity may be used. The pre-heating requirement will depend on the size and type of the base material.

3.01

Use a short arc. Hold the electrode almost at right angles to the workpiece and use a weaving movement. The length of each stroke should not exceed three times the electrode dia­ meter. Remove the slag from the bead with chipping hammer and wire brush before starting on the next bead. Cast cupro-aluminium parts and similar materials must be annealed after welding by heating the welding area to 650°C. The workpiece must then be allowed to cool down slowly to below 500°C to ensure that the metal does not lose any of its properties.

189