New developments in advanced welding

Future trends

The following trends can be anticipated in GMA welding within the next

five years. The following areas are important:

(1) process simulation and modelling,

(2) sensing and control,

(3) cost reduction and

(4) new applications.

• Improved computer simulations of the welding process and implementation in production welding;

• Improved sensing and signal acquisition before, during and after welding and inclusion in a comprehensive control system. This effort will require increased sensitivity to downstream manufacturing practices to improve part fitup;

• Improved power source technology via digital controls and improved control of the welding arcs;

• Applications: extension of the process to reduced base metal thickness and higher deposition rates. Even further miniaturisation (or MEMS: micro­electro-mechanical systems) can be expected to penetrate the GMAW equipment world;

• Automation: remote operation (depths, heights, hazardous environments);

• In semi-automatic applications: integration of all essential functions in the welding torch;

• Deposition rates and cost reductions - more hybrid and new process variants, lower cost filler wires and shielding gases (push toward self­shielded fluxed core arc welding;

• Controls: digital networks, qualifications.

1.2 References

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