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ALUMAG 235
Unitor ALUMAG 235 is used for welding pure aluminium, seawaterresistant aluminum and cast aluminium.
Clean the joints and adjacent surfaces thoroughly. Use a stainless steel brush, not an ordinary steel brush which will rub iron oxides into the aluminum and contaminate the weld pool. Cast aluminum should be preheated to approximately 300°C. Make sure that pre heated cast components are well supported, so that they do not sag when the temperature rises. Cast alloys that have been pre-heated must be allowed to cool slowly after being welded.
Gas welding
In gas welding a flame with a slight excess of acetylene is used, together with ALUFLUX 234 F, a flux which reduces oxides and counteracts oxidation in the welding zone. This flux which is in powder form can be mixed with clean water into a paste that is painted onto the welding area and the welding rod. If the work pieces are thick, it is also recommended to use flux at the back of the joint. The flux is highly corrosive on aluminum and should be removed immediately after welding, by scrubbing with hot water.
TIG (GTAW) welding
For TIG welding of aluminium it is necessary to use a special alternating current (AC) power source. AC is required to break the oxide layer on the aluminium surface.
Repair of aluminium cover plate.
Carburising flame.
Slight surplus of acetylene.
3.04
Remember that fluxes can be contaminated. Therefore, always replace the lid after use.
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