1.1 This specification covers the requirements for 33 grades of titanium and titanium alloy welded pipe intended for general corrosion resisting and elevated temperature service as follows: 1.1.1 Grade 1—Unalloyed titanium, low oxygen,1.1.2 Grade 2—Unalloyed titanium, standard oxygen,1.1.2.1 Grade 2H—Unalloyed titanium (Grade 2 with 58 ksi minimum UTS),1.1.3 Grade 3—Unalloyed titanium, medium oxygen,1.1.4 <