are proprietary to the manufacturer. After upsetting, the tube then goes through a heat treating process. Drill pipe steel is commonly quenched and tempered to achieve high yield strengths (135 ksi is a common tube yield strength).

The tool joints (connectors) are also received by the manufacturer as green tubes. After a quench and temper heat treat, the tool joints are cut into box (female) and pin (male) threads. Tool joints are commonly 120 ksi Specified Minimum Yield Strength (SMYS), rather than