Carbide Drill Insert Extends Bit Life, Improves Penetration

Rockmore International has developed a new carbide insert design for their button bits. As the company explains, in percussion drilling penetration rates depend on efficient crack propagation. With a conventional hemispherical insert, there is a single tangent point striking the rock, resulting in the rapid development of wear flats. Rockmore says its new MultiPoint carbide insert design provides multiple strike points for more efficient rock fracture and longer insert life, and states that extensive rock-drilling trials showed that button bits with MultiPoint inserts last up to 20% longer than the standard hemispherical design, and can increase penetration rates by 10%. Wear flats appeared later in the insert life than with hemispherical inserts. Testing also showed that the MultiPoint inserts provided smoother bit rotation and advancement. The MultiPoint design is currently available in ½-in. to ¾-in. (12 to 19 mm) diameter carbide inserts, for Rockmore’s DTH and top-hammer bits of 3.5-in. to 10-in. (89 to 254 mm) diameter.

As featured in Womp 2009 Vol 06 -