What are drilling parameters?

Drilling parameters play a large role in helping drillers achieve superior drilling performance and long equipment life. They are basic recommendations that help guide a driller avoid burning core bits or damaging other drilling equipment, and help achieve a good rate of penetration and core recovery.

How do I find the optimum ROP for diamond drilling?

The ROP is the key parameter in diamond drilling. Finding the optimum ROP for a given type of rock, ground condition, core bit and type of diamond drill rig will improve drilling performance. To find the optimum ROP, you should start by using the ROP suggested on the bit label.

Does rock strength affect drill rate?

When operating eficiently, rock strength and bit aggressive-ness efect the drill rate, but large changes in drill rate are usually due to ineficiency or dysfunction in the rock cutting process. If the bit is eficient, it is only necessary to raise the WOB or RPM in order to drill faster.

What are the parameters of a rock quality designation (RQD)?

Uniaxial compressive strength of intact rock material. Rock quality designation (RQD). Spacing of discontinuities. Groundwater conditions. Orientation of discontinuities. All of these are measurable in the field and can also be obtained from borehole data. The rating of each of these parameters are summarised to give a value of RMR.

What is a drillstring elongation?

The driller applies a high WOB, locks the top-drive position, and continues rotation. The rotating bit drills ahead and the locked string elongates, transferring the drillstring weight that had been applied to the bit back to the hook. The amount of drillstring elongation is called “stretch”.

How do you calculate ROP in a drill-of test?

The ROP can be calculated and plotted during each incre- Figure DP-5: Drill-of test conducted by observing the time required to drill of 3,000-lb increments of weight on bit. The highest ROP occurs at the WOB corresponding to the shortest required time per increment.