Surface Set Diamond Core Bits BQ NQ HQ PQ Sizes

A range of surface set core bits are manufactured to the highest quality standards to give long service life and maximum penetration in soft to hard formations. The range includes a variety of diamond grades, stone sizes and face profiles enabling a cost effective solution to be taken for most conditions.

Diamond Grades
Drill 1 : Very good quality, processed, well rounded diamonds, free from flaws for medium to very hard fromations.

Drill 2 : Good quality, processed, rounded diamonds, free from flaws for soft to medium formations.

Carbonado : Microcrystalline natural diamonds with a very tough structure, used in severe drilling conditions where conventional natural stones tend to fracture, such as badly fractured formations.

Diamond Stone Size: Stones Per Carat (spc)
10/15 spc: Soft to Medium Formation

20/25 spc: Medium to Hard Formation

30/40 spc: Medium Hard to Hard Formation

40/60 spc: Hard Formation

60/80 spc: Hard to Very Hard Formation

Face Profiles
Semi Round : Standard profile. Very strong in hard broken formation.

Stepped : High penetration and stability but fragile in hard fractured formation.

Conical : Good penetration rate and stability. Stronger than stepped profile.

Pilot : Good core recovery in soft, friable formation especially when used with face discharge. Good stablisation but fragile nose.

Biconical : Only used on thick kerf core bits in soft unfractured formation.

See also: 
Tungsten Carbide Core Bits
Geotechnical & PDC Diamond Core Bits