Description
A range of surface set bits manufactured to the highest quality standards to give long service life and a maximum rate of 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 chosen for most conditions.
Diamond grades
Super N1: Highest quality unprocessed natural drilling diamonds, specially selected and suitable for hard to very hard formations.
Drill 1: Very good quality, processed, well-rounded diamonds, free from flaws for medium to very hard rock.
Drill 2: Good quality, processed, rounded diamonds, free from flaws for soft to medium formations.
Regular: Congo diamonds supplied in larger stone sizes, suitable only for soft formations.
Carbonado: Microcrystalline natural diamond with a very tough structure, used in severe drilling conditions where conventional natural stones tend to fracture, such as badly broken formations.
Stone sizes (SPC)
10/15 stones per carat: Soft to Medium rock.
20/25 stones per carat: Medium-hard rock.
30/40 stones per carat: Medium hard to Hard.
40/60 stones per carat: Hard rock
60/80 stones per carat: Hard to Very hard rock.
Matrix type
Available in two matrix types: O for normal abrasion and E for extreme abrasion resistance.
Waterways
Usually shallow to allow even cooling and flushing of the face. Face discharge ports are used only in soft formations to minimise core-washing.
Face profiles
Semi round: Standard profile. Very strong in hard, broken ground, but requiring high bit load to achieve fast penetration.
Stepped: High penetration and stability but fragile in hard, fractured formations.
Conical: Good penetration rate and stability. Stronger than stepped profile but not as fast penetration.
Pilot: Good core recovery in soft, friable formations especially when used with face-discharge waterways. Good stabilisation. Fragile nose.
Biconical: Only used on thick kerf bits in soft un-fractured formations. Good penetration but fragile nose.