Hole Products - Products

Impregnated Bit Selection Guide

Impregnated bits are typically designated by "Series." Each series is designed to work under specific
conditions of ground hardness and abrasiveness.

Please refer to the selection table to identify the appropriate series for your drilling conditions.

Hole Products Bit Selection Guidelines
ROCK TYPE	CHARACTERISTICS	HOLE PRODUCTS IMPREGNATED BIT SERIES GUIDE	CONDITION	HOLE PRODUCTS DIAMOND SURFACE SET SIZE GUIDE
EXTREMELY HARD Chert, Glassy Quartzite, Ironstone, Jasperite, Volcanic Tuff	Non-Abrasive Very Fine Grained Competent	10 *	All Types	Not Recommended Use Impregnated Bit
VERY HARD Dolerite, Gneiss, Granite, Porphyry Quartzite, Rhyolite,	Non-Abrasive Fine Grained Competent	8,9	All Types	Not Recommended Use Impregnated Bit
HARD Andesite, Basalt, Dolerite, Gabbro, Quartz, Silicified Volcanic	Moderately Abrasive Fine to Medium Grained Competent to Fractured	7,8	All Types	Not Recommended Use Impregnated Bit
MEDIUM HARD Diabase, Dolomite, Pegmatite, Sandstone, Schist, Siltstone	Moderately Abrasive Medium to Coarse Grained Competent to Fractured	6,7	Competent Broken	45/55 SPC 35-45 SPC
SOFT Limestone, Marl, Peridotite, Serpentine, Shale, Weathered Granite,	Abrasive Medium to Coarse Grained Competent to Fractured	4	Competent Broken	25/35 SPC 15/25 SPC
VERY SOFT Clay, Gypsum, Potash, Talc,	Abrasive Coarse Grained Fractured	2,4	Competent Broken	15/25 SPC 10/15 SPC 6/10 SPC
VERY ABRASIVE Conglomerate, Hard Shale, Limestone, Sandstone	Very Abrasive Coarse Grained Highly Fractured	2	All Types	10/15 SPC 6/10 SPC