One of the welding processes that used in Engineering field is the electrogas welding. There are several types of welding processes similar to. Abstract. Electrogas arc welding (EGW) is used for vertical position welding of sheer strakes and hatch side coamings of container ships because of its higher. (13 mm) could be satisfactorily welded in the vertical position in a single pass. This technique is called electrogas welding (EGW). EGW has enjoyed steady.
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Water-cooled copper retaining shoes are elsctrogas used on each side of the joint to retain the molten weld metal. Compared to other processes, a large amount of molten metal is present during welding, and this poses an additional safety and fire hazard.
The condition shown in Figure 7. The weld should be carefully exam- designed to accommodate as much variation as practical, ined in these regions.
The cavity can be filled with sound metal deposited by conventional arc welding processes. Before machining commences two water-cooling shoes  are placed on each side of the weld zone weldin prevent the melt flowing out during the welding process.
Electrogas welding of quenched and tempered or normalized steels may not be permitted by some codes. Operators should also check the workpiece t,o verify that the joint is correct, and that the base metal condition will allow free passage of the welding head to the top of the joint. Vertical travel controls, either electrical, optical, or manual, maintain a given electrode extension, with the top of the movable shoe a specific distance above the molten weld pool.
As shown in Figure 7. It must be narrow enough to be contained in the gap with clearance to permit horizontal oscillation, if used, between the two shoes. For selding, an electrode meeting the requirements of the EG62 classification, also meets the requirements of EG6Z. For the more susceptible steels, each of the other factors becomes more critical.
Most of the heat generated in electrogas welding is conducted into the workpieces.
Electro gas welding
Check operation of ventilating equipment if used. Moreover, it is fairly easy to prevent. Some standards presently permitting use of the EGW process sometimes with additional restrictions are listed below: Electrode is used without externally supplied shield gas. Sliding shoes mayor may not contain gas ports for supplying shielding gas directly into the cavity formed by the shoes and the weld groove.
Specific line-up settings and tolerances are listed in each welding procedure. The weld seam has lesser cracks than electroslag welding. The general classification system of ewlding for EGW is illustrated in Figure 7.
Setup for Electrogas Welding (EGW) | Metallurgy
After reading this article you will learn about the setup for Electrogas Welding EGW with the help of diagrams. BoxMiami, Florida The moving shoe molds the metal at the weld face, and the stationary shoe molds the root electroas. The sump is cut away after welding.
To prevent them from melting, they are made of copper and are water-cooled. In general, increasing root opening or the voltage increases the form factor, while increasing the current or decreasing the root opening decreases the form factor.
Shielding gas for flux cored electrodes is as noted eelctrogas Table 7. An opening should be left so that gases expanding between the sump and the work as a result of the welding heat are driven away from the molten weld metal.
This also will reduce the slag burden. The welding head is attached to an apparatus that elevates during the welding process. Note that there are two strength classifications, and that different base metals are used in the standard test weldment for each classification.
Applications involving aluminum alloys and stainless steel will not be discussed, although successful examples have been reported. The required properties are normally obtained in the as-welded condition. A wire feeder is used to supply the electrode, which is selected based on the material being welded. Fixed backup bars must reach to the top of the runoff area, finishing 1 to 2 in.