tubing and casing strings are the main parts of the well construction. all wells drilled for the purpose of oil or gas production (or injecting materials into underground formations) must be cased with material with sufficient strength and functionality. tubing and casing are key portions of octg

induction weldingthe two main aspects of hf welding are processes and power supplies. each of these can be broken down further into subcategories. processes. the two hf welding processes are hf contact and hf induction. in both processes, the equipment that provides the electrical current