Manufactures of premium quality Diamond Core Bits, Reamer Shells, PCD Bits,
  Casing Shoes and Wedging Bits.

CORE BITS- Selection chart Rock Characteristics
Extremely Hard Non-Abrasive Very Fine Grained Competent	12-15 10-12
Very Hard Non-abrasive Fine Grained Competent	8-10 7-9
Hard Moderately Abrasive Fine To Medium Grained Competent to Fractured	7-9 6-8
Medium Hard Moderately Abrasive Medium to Coarse Grained Competent to Fractured	6-8 6
Medium Soft Abrasive Medium to Coarse Grained Competent to Fractured	2
Very Abrasive Coarse Grained Highly Fractured Abrasive	1

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