8 1/2 inch PDC bit M166
|Number of Blades||6|
|Primary Cutter Size||16mm|
|Gauge Length||2.2 Inch|
|Flow Rate (lps)||22~35|
Soft to medium-hard formations with low
compressive strength interbedded with hard
layer , such as claystone,marl,lignite,
The M1663 is a matrix body PDC bit with 6
curved blade with back-reaming and spiral
gauge protection. Optimized Hydraulie design
and enhanced cleaing and cooling effects of
the bits to prevent bit from balling.
Matrix-body PDC bits are commonly preferred over steel-body bits for environments in which body erosion is likely to cause a bit to fail. For diamond-impregnated bits, only matrix-body construction can be used.
** Steel-body bits
The strength and ductility of steel give steel-bit bodies high resistance to impact loading. Steel bodies are considerably stronger than matrix bodies.A beneficial feature of steel bits is that they can easily be rebuilt a number of times because worn or damaged cutters can be replaced rather easily. This is a particular advantage for operators in low-cost drilling environments.
|Rock hardness and bit selection|
|Cone bit IADC code||PDC||Formation||Rock Types||Compressive strength (Mpa)||ROP(m/h)|
|111/124||M/S112~M/S223||Very soft: low viscosity, low compressive strength.||
|116/137||M/S222~M/S323||Soft: the formation is soft with low compressive strength and good drillability.||
|417/527||M/S323~M/S433||Medium soft: weak to medium, low compressive strength.||
|517/537||M322~M443||Medium to hard formation with high compressive strength and poor abrasion resistance.||
|537/617||M422~M444||Medium hardness: hard, dense formation with high compressive strength and moderate wear.||