The rate of penetration, or ROP, is the speed at which the drill bit advances through rock and is often measured in inches per minute or meters per hour.
The ROP is seen as a benchmark for most drillers. The better your ROP, the faster your drill goes through rock and the faster you deepen your borehole. It has a direct impact on your productivity. As a result drillers look for ways to improve their ROP so they can recuperate more core quickly. Whenever you change a piece of equipment or change a process, you will compare the ROP before and after this change to see how it has been affected. Let’s look at some variables that will affect ROP.
Core bit matrix: Always choose a core bit that is suitable for the type of rock you will be drilling. Consider core bits that are self-sharpening, such as the Hero 11 Abrasive, as regular sharpening will optimize your penetration rate.
Crown heights: Core bits with a higher crown that is impregnated with diamonds, such as the Vulcan series, may improve penetration rates. For example, if you are averaging 200 meters with a 13 mm crown, but your borehole is 250 meters, a Vulcan bit can allow you to complete the hole without changing the bit.
Waterway configuration: The number of waterways, the pattern and width between waterways should always be considered and chosen according to ground type.
Water flow: Drilling fluid must reach the core bit to cool it and to flush away rock cutting. The use of drilling fluid additives, such as DD-2000 and Torqueless can cool the bit, help flush the cuttings, and reduce wear and tear on equipment.
Rotation speed: Rotation speed should be chosen based on the diameter of the system you are using. This is the first step however, if you are penetrating the rock quickly, it is possible to rotate the rods faster which will enhance ROP. Or if you are having difficulty penetrating the rock, you can reduce RPM and help increase ROP.
Bit pressure: You should only put as much bit pressure as needed to advance. To achieve a good penetration rate, you must aim for the ideal combination of rotation speed and bit pressure and this will change with each rod added.
Your rate of penetration will be impacted by all of the variables above, and the ability to improve your rate is also affected by drilling experience. To learn more about each variable in detail and rate of penetration in general, get our new ebook, “Essential Guide to Improving Your Rate of Penetration”.