This feature includes small, round-top inserts located between conventional gauge inserts or teeth. GageGuard proves ideal on soft-to-medium formation bits, especially when drilling formation intervals of moderate-compressive strength and high abrasivity. The rounded inserts ream the gauge of the well bore, relieving the gauge inserts from the abrasive reaming action.
ReedHycalog® GageGuard inserts are useful in applications where gauge insert wear or gauge insert breakage limit bit performance. They enhance performance of both tooth and insert bits in these applications.

GageGuard improves gauge durability by relieving the primary gauge teeth from part of their high-velocity sliding action against the hole wall. Contact between gauge tooth and hole wall starts well above the hole bottom, with a high velocity and low force reaming action. As the bit and cones rotate further, the primary gauge tooth slides down the hole wall and slightly toward the bit center until it reaches the hole bottom. During this cutting cycle, sliding velocity continually decreases while force on the tooth increases as the gauge insert moves to the bottom.