Welds/welding

BET24909 European collaboration in creep data development for welds weld[Pg.936]

Imperfection f When required examination is Girth and miter-joint hutt welds Longitudinal hutt welds Fillet, socket, seal, and reinforcement attachment welds Welded branch connections and fabricated laps... 

Welded Welded joints connect the subassemblies of some fluid power systems, especially in high-pressure systems that use pipe for fluid lines. The welding is done according to standard specifications that define the materials and techniques. 

Automatic Welding welding in which the welding variables and the means of making the weld are controlled by machine. 

Fusion Welding welding in which the weld is made between metals in a molten state without the application of pressure. 

Resistance Welding welding in which force is applied to surfaces in contact and in which the heat for welding is produced by the passage of electric current through the electrical resistance at, and adjacent to, these surfaces. 

Semi-automatic Welding welding in which some of the variables are automatically controlled, but manual guidance is necessary. 

High temperature hydrogen attack damage may occur in welds, weld HAZs, or base metal. Even within these specific areas, the degree of damage may vary widely. Consequently,... 

Rowe, M.D., Nelson, T.W., and Lippold, J.C., Hydrogen-induced cracking along the fusion boundary of dissimilar metal welds, Welding Res., February, 1999, p. 31. 

Welding Without Filler Metal (Autogenous Welding). Weld joint geometry shall be square-butt single welded. 

Attachment of suction and discharge nozzles shall be by means of full-fusion, full-penetration welds. Weld neck flanges are required for pumps handling flammable or hazardous liquids. Dissimilar metal weldments are not allowed. 

Lap fillet weld Double V butt Corner weld weld... 

If chlorinated solvents are used with titanium surfaces, they must be completely removed prior to bonding. Chlorinated solvents give rise to stress corrosion cracking in the vicinity of welds. Welding of titanium often occurs in the same plant as adhesive bonding, and it is sometimes done on the same parts. So the best practice is to avoid the use of chlorinated solvents completely. Several airframe manufacturers that fabricate titanium alloys no longer permit the use of chlorinated solvents. 

To ensure that a satisfactory quality of welding is maintained, welding-machine operators and welders working on the pressure parts of vessels are required to pass welder approval tests, which are designed to test their competence to make sound welds. Welding and brazing qualifications are discussed in Section IX of the ASME BPV Code. 

Argon is also used in welding. Welding is the process by which two metals are joined to each other. In most cases, the two metals are heated to very high temperatures. As they get hot, they melt together. 

---