Downhole · Completion
Production Tubing & Accessories
The string of pipe that carries well fluid to surface, together with the short subs, called jewelry, that are made up into it.
What it does
Gives the produced fluid a sealed path inside the casing. Crossovers, swages, perforated nipples and plugs adapt sizes, let fluid in and close off the end of the string.
Basics
| Standard | API Spec 5CT |
| Selected by | Rates, pressures, depth, temperature and corrosion |
| Accessories | Crossovers, swages, perforated nipples, bull plugs |
Common failures
- Internal corrosion or pitting from produced fluids
- Thread leak at a connection
- Grade or size not suited to the loads
Troubleshooting
- Symptom
- Tubing to annulus communication
- Likely cause
- Hole or thread leak in the string
- What to check
- Pressure test the tubing, plan a pull and inspection
- Symptom
- Rate drops with rising tubing restriction
- Likely cause
- Scale or paraffin inside the tubing
- What to check
- Check deposits, review chemical treatment