In water well drilling, the drill bit is known as the "teeth that bite through rock." Choosing the right bit leads to fast drilling, low cost, and high well quality; choosing the wrong bit results in slow footage, frequent tripping, or even bit scrapping and borehole collapse.

Common Formations and Drilling Difficulties

• Loose overburden: Clay, sand, gravel, and pebble layers are prone to hole collapse and mud loss.
• Soft sedimentary rock: Mudstone, shale, and soft sandstone are prone to bit balling and deviation.
• Hard sedimentary rock: Dense sandstone, limestone, and dolomite are highly abrasive with slow ROP.
• Igneous/metamorphic rock: Granite, gneiss, and quartzite have extremely high hardness and strong abrasiveness.

Bit Type Selection Guide

• Soft to medium-hard formations: PDC drag bits or concave bits with strong aggressiveness.
• Hard and abrasive formations: Impregnated diamond bits or TCI tricone bits.
• Gravel and interbedded formations: Step-type PDC bits or tricone pilot bits.

Correct formation-bit matching is the key to improving drilling efficiency. Provide your geological conditions, and our technical team will recommend the most suitable bit model for you.