2. Reaming Operation Summary

Basic Operating Data

• Drilling interval: 6235–7045 m

• Reamed interval: 6223–7013 m

• Formation: Kumglemu Group

• Lithology: salt rock, mudstone, gypsum

Drilling Parameters

• WOB: 3–8 T

• RPM: 60–80

• Torque: 6–15 kN·m

• Flow rate: 23–25 L/s

• Pump pressure: 28–31 MPa

Mud Properties

• Density: 2.35 g/cm³

• Viscosity: 72–76 s

3. BHA & Tool Performance

A 9.5″ × 10.5″ hydraulic reamer specifically designed for salt formations was used.
Total run duration:

• Pure drilling: 212 h

• Total downhole time: 298 h

Performance results:

• Reamer condition: no tooth loss or damage

• Bit condition: intact, minimal wear

• Rating: 1-1-WT-A-X-X-X-0-NO-BHA

The tool successfully expanded the 9-1/2″ hole to 10-1/2″ in a single trip.

4. Operational Achievements

This operation represents:

• The first reaming-while-drilling trial in the Tarim Oilfield

• The first successful hydraulic reamer application in salt-formation sections of the Kumglemu Group

Key performance highlights:

• Successfully activated at 6256 m

• Reamed through the gypsum interval at 7045 m

• Zero downhole or personnel incidents

• Total reaming time: 231 h

• Downhole temperature: static ~150°C, circulating ~145°C

5. Technical Benefits Observed

Compared with conventional PDC drilling:

• No significant increase in torque or drilling time in the salt formation

• Average ROP in salt: 9–11 m/h

• Improved tripping efficiency—no sticking or obstructions

• Reduced non-productive time

• Enlarged borehole minimised formation creep risks

6. Conclusion

The successful application in Well Keshen-17 provides valuable operational experience for safe and efficient drilling in the salt formations of the Kumglemu Group within the Keshen Piedmont block. It demonstrated high-quality execution, operational safety, and set a new performance benchmark.