Coal seams are soft with
developed bedding, making borehole collapse prone during drilling.water well drilling rig
- Collapse not only affects borehole quality but may also bury drilling tools, causing economic losses.
To prevent collapse:
2. Adopt mud wall protection: adjust mud density and viscosity per coal seam traits to enhance wall support.
3. For severely broken coal seams, use casing protection: run casing in time as drilling depth increases to isolate unstable seams.
4. Optimize drilling techniques: control speed to avoid excessive coal seam disturbance; apply low rotation speed and high WOB to reduce borehole wall stress.
5. Combining multiple anti-collapse technologies ensures smooth hole formation for water well rigs in coal seams.water well drilling rig
