Submerged arc fluxes

Figure Al compares moistures levels of electrode coatings and submerged-arc fluxes. (The histograms show the relative frequency of measurements over the total range.) Typical levels of moisture in both agglomerated and fused submerged-arc fluxes are shown, hut it is emphasised that in this process the filler wire is an additional source of potential hydrogen.

Consumables to be tested shall be prepared according to the information wanted from the results of the test. For example, manual metal arc electrodes or submerged-arc flux would normally be dried... 

Often used when MMA electrodes and submerged-arc fluxes are dried at high temperatures, e.g. above about 250 °C, to remove moisture. When fluxes are dried at temperatures above about 800 °C the term pre-sintering is sometimes used. 

Submerged-arc Welding metal-arc welding in which a bare wire electrode is used the arc is enveloped in flux, some of which fuses to forin a removable covering of slag on the weld. 

A submerged-arc process is commonly used for welding stainless steels and carbon steels when an automatic operation is acceptable. The electrode is a continuous roll of wire fed at an automatically controlled rate. The arc is submerged in a granulated flux which serves the same purpose as the coating on the rods in the shielded-arc process. The appearance and quality of the submerged-arc weld is better than that obtained by an ordinary shielded-arc manual process however, the automatic process is limited in its applications to main seams or similar long-run operations. 

Moisture in the coating of manual metal-arc electrodes, in the flux used in submerged-arc welding or in flux-cored wires. 

This technique was devised specifically for testing covered electrodes but has been adapted to examine gas shielded welding processes with solid and flux-cored wires and also the submerged-arc process. It is important to note that results are not necessarily directly comparable between processes (see Appendix A). A sketch of the copper jig used for the submerged-arc process is given in Fig. B4b. 

It comprises an outer sheath of steel (usually mild steel) which contains flux and/or metallic ingredients. The sheath may be a fine hollow tube or a strip wrapped round the core. Cored wires may be used for MAG, MIG or submerged-arc welding. 

In submerged arc-welding, the strip electrode is fed from a coil into the flux bed and fused in the arc. The width of the weld deposit corresponds approximately to the width of the electrode, and mixing with the substrate depends on the process parameters. The procedure is preferably used to clad stainless steels. Because of bum-off and mixing, the electrode must be overalloyed to compensate for the loss of important elements. 

Explanation of material abbreviations 10,12 or 15, mean value of carbon content in mass% Kh, chromium M, molybdenum N, nickel F, vanadium T, titanium B, niobium Kh2/N2, mean value of chromium/nickel content Sv, weld wire A, clean steel AA, very clean steel AN, EC, flux for submerged arc welding. 

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