Download - Atlas Copco

Secoroc Rock Drilling Tools
A Complete Rotary Drilling System
Rotary Drill String PV-235

Floating Cushion
Shock Sub
Top Spindle Sub
Top Thread Saver Sub
Drill String Components
Drill Pipe Lifting Bail
TEAMALLOY TM
Drill Pipe
Carousel Pot/Cup
TEAMALLOY TM
Starter Drill Pipe
CENTEROLL TM
Deck Bushing
Deck Bushing
DURALLOY TM
Bit Sub
EZ-DRILL TM
Roller Stabilizer
Bit Lifting Bail
Secoroc Tricone Drill Bit
Bit Breaker Basket
Pit Viper Series

In rotary drilling, the selection of each purpose suited drill string component
is vital to achieve accurate holes and operational efficiency –
parameters which affect operational costs.
When developing a rotary drilling system, most of the attention is given to the drill
rig – the capital equipment that requires significant investment and hence a planned
payback. The second priority in the system tends to be choice of rotary tricone drill
bit. However, to utilize the full power and capacity of the rig and the bit and at the
same time increase service life and productivity, serious consideration should also be
given to each component within the drill string.
The optimal drill string includes a shock absorber at the top, a rotary
deck bushing to centralize the drill string as it passes through the deck
of the drill rig, strong and straight drill pipes and finally a hole stabilizing
roller stabilizer or bit sub-adaptor to optimize the performance.
Giving the necessary attention to every part of the drill string will lead
to the lowest total drill operating costs.
The primary purpose of the drill string is to transmit the rotational torque
and weight from the rotary head power source to the rock breaking drill
bit. As in every rock drilling method, the power must be transmitted as
efficiently as possible, and return as few vibrations as possible, as these
cause unnecessary wear on the drill rig and reduces penetration rates.
When selecting components for the drill string, attention must be given
to the different roles of the support tools in the string. With the Secoroc
rotary drill string the aim is to always:
• Absorb damaging vibrations from the bit.
• Reduce wear on the drill rig’s rotary drive, mast and power train.
• Improve transmission energy from the rotary head to the drill bit.
With the Secoroc rotary drill string the aim is to always:
• Centralize drill string within the hole, ensuring axial alignment
top to bottom.
• Longer and more effective bit life.
• Compliment performance potential of the drill rig and drill bit.
• Reduce friction as the drill string passes through the drill rig deck.
With the Secoroc rotary drill string the aim is to always:
• Stabilize the hole wall to prevent hole caving in softer formations.
• Increase penetration rates, lowering total drilling costs.
• Achieve blasthole accuracy for improved blasting efficiency.
• Improve the end result – the correct fragmentation of the blasted rock for
lower downstream operating costs!