Torque
Torque indications are very useful as a check on smooth operation. No
absolute values have been set up, but a steady torque is an indication that
the previous three factors are well coordinated.
Bit Stabilization
A diamond is extremely strong in compression, but relatively weak in
shear, and needs constant cooling when on bottom. The bit is designed and
the rake of the diamonds set, so that a constant vertical load on the bit
keeps an even compressive load on the diamonds, and even distribution of
coolant fluid over the bit face. If there is lateral movement or tilting of the
bit, an uneven shear load can be put on the diamonds with coolant leakage
on the opposite side of the bit.
Any of the standard “stiff-hookup” or packed hole assemblies are suitable
for stabilization when running diamond bits. It is recommended that full
gauge stabilizers be run near the bit, and at 10 feet and 40 feet from the
bottom.
Torque indications are very useful as a check on smooth operation. No
absolute values have been set up, but a steady torque is an indication that
the previous three factors are well coordinated.
Bit Stabilization
A diamond is extremely strong in compression, but relatively weak in
shear, and needs constant cooling when on bottom. The bit is designed and
the rake of the diamonds set, so that a constant vertical load on the bit
keeps an even compressive load on the diamonds, and even distribution of
coolant fluid over the bit face. If there is lateral movement or tilting of the
bit, an uneven shear load can be put on the diamonds with coolant leakage
on the opposite side of the bit.
Any of the standard “stiff-hookup” or packed hole assemblies are suitable
for stabilization when running diamond bits. It is recommended that full
gauge stabilizers be run near the bit, and at 10 feet and 40 feet from the
bottom.
