Drill string · Drilling
Drill Pipe
Steel pipe fitted with threaded ends called tool joints that makes up most of the drill string.
What it does
Carries drilling fluid down to the bit and lets the rig raise, lower and rotate the bottomhole assembly. Joints stay connected in stands of two or three during trips to save time.
Basics
| Ends | Tool joints |
| Stands | Two or three joints, racked in the derrick |
| Connections | Torqued to the right value |
Common failures
- Parting of the string from fatigue or excessive torque
Troubleshooting
- Symptom
- Gradual loss of pump pressure
- Likely cause
- Eroded hole in a pipe body or joint
- What to check
- Pull out and inspect the string before it parts