AWS D10.6 – D10.6M pdf free download

AWS D10.6 – D10.6M pdf free download.Gas Tungsten Arc Welding of Titanium Piping and Tubing.
7. Titanium Grades (Base Metal)
Six grades of titanium are commonly used for pipe and tubing. They are covered by ASTM B 337 for pipe, B 338 for tubing, and B 363 for fittings. (See Tables 1 and 2 for the chemical and mechanical requirements for B 337. Requirements for B 338 and B 363 are similar to those for B 337.) The microstructure of these grades is essentially single-phase alpha titanium. These grades arc not hardenable by heat treatment. Certain other grades such as alpha-beta titanium alloys have been fabricated into pipe, however, they are not covered by this document. The manufacturers of these alloys should be consulted for welding recommendations.
8. Filler Metals
8.1 Filler Metal Classification. Bare welding rods and electrodes are commercially available for welding titanium pipe and should conform to AWS Classifications ERTi- 1, ERTi-2, ERTi-3, ERTi-4, ERTi-7, ERT1-9, ERT1- 9ELI, and ERTi-l2. The other welding rods listed in AWS A5.16 do not apply to welding the base metals covered by this standard. See Table 3 for chemical composition requirements for filler metals.
8.2 Welding Rod Size. For manual welding, welding rods up to 1/16 in. (1.6 mm) diameter are suitable for welding pipe with wall thickness up to about 0.175 in. (4.4 mm). Above that thickness, 3/32 in. (2.4 mm), 1/8 in. (3.2 mm), or 5/32 in. (4.0 mm) welding rod may be used.
Welding rods are supplied in straight lengths or in coils without support. Welding wire is wound on spools for automatic gas tungsten arc welding (GTAW). For automatic welding, wire diameters of 0.035 in. (0.9 mm), 0.045 in. (1.1 mm), and 1/16 in. (1.6 mm) are available.
8.3 Filler Metal Application. Generally, titanium filler metal is selected to match the composition of the base metal. However, a corrosive environment or high- temperature service may dictate the use of nonmatching filler metals. ERT1-l, ERT1-2, ERT1-3, and ERT1-4 filler metals are referred to as commercially pure titanium, with the level of impurities increasing slightly from ERT1- I to ERT1-4. While any of these alloys may be used with B337 or B338 Grades 1, 2, and 3, service conditions should he considered. Normally, ERTi-7 would be used with base metal Grade 7, ERTi-9 with Grade 9, and ERTi-12 with Grade 12. if corrosive environment or high-temperature-strength requirements did not dictate other filler metals. Refer to the Appendix of the latest edition of AWS AS. 16.
9. Joint Design
Square-groove butt joints should be used on piping with walls up 100.125 in. (3.2 mm) thick and a single-Vgroove (75 degree groove angle) on walls from 0.093 in. (2.4 mm) to 0.375 in. (9.5 mm) thick. U-grooves should be used for wall thicknesses over 0.375 in. (9.5 mm). The various joint designs are shown in Figure 1.
10. Joint Preparation
Joints are best prepared by sawing, machining, or milling. Such operations should be done with care to ensure accurate fit. Excessive heating, resulting in discoloration, should be avoided. Hand grinding can be employed if done with caution to avoid overheating. Clean grinding wheels should be used, and they should be dressed frequently. Carbide rotary files are also useful. Soft or rubber-bonded wheels should not be used. Abrasive particles embedded in ground surfaces should he removed by filing or machining. It is important that tools such as grinding wheels and files that can become contaminated with other metals be used only for titanium. Clamps and fixtures should be kept clean to minimize contamination by grease and dirt in the joint area. Chlorinated cutting lubricants should not be used.AWS D10.6 – D10.6M pdf download.