Preparation for welding
The need for degreasing and oxide removal has been covered in Chapter 2. This chapter will review both the handling and storage of aluminium and the options available for cutting, machining and pickling and cleaning of the alloys prior to welding. There are a number of thermal processes available to the fabricator for either cutting or weld preparing, as discussed in this chapter. One process that is not available for the cutting of aluminium, however, is the oxy-gas process used so widely to cut the carbon and low-alloy steels. Instead, arc or power beam processes or machining must be used to provide the correct edge preparations for welding.
Correct and accurate edge preparations are essential for the production of sound, defect-free welds in aluminium. Edge preparations are required to achieve full penetration to the root of the joint, to enable the correct analysis of weld metal to be achieved, to assist the welder to produce defect - free joints and to do this at an acceptable cost. The design of edge preparations for specific welding processes will be dealt with in the chapters dealing with the individual processes.