Tips To Perform Diamond Drilling Through Hard Rock

Tips To Perform Diamond Drilling Through Hard Rock

Drilling in extremely hard rock is not at all an easy task. There are several things that a diamond driller needs to consider in this regard to accomplish their job. To understand this well, one should have a good idea about the Mohs scale. Really hard rock in drilling is specifically about 7 to 8 on the Mohs scale. 

Mohs hardness scale is a chart that shows the relative hardness of different minerals. This scale consists of numbers from 1 to 10, and here, 10 suggests the hardest minerals, whereas 1 suggests the softest ones. Hard rock includes quartz and gneiss, and extremely hard rocks are taconite, quartzite, and jasperite. 

Now that you know about the Mohs scale, it is time to determine how hard your rock is. Well, one of the easiest and most reliable ways to determine the hardness of rock involves performing a scratch test. 

This specific test uses a hardness kit and compares the results with the Mohs scale. If you do not have such tools, you can still determine the hardness by using a metal saw or a pocket knife. But, the results may not be as accurate in this case. 

So, if you are performing diamond drilling through hard rock, then there are some of the essential tips that you need to consider. Here, we will talk about these tips to help you make your diamond drilling work more manageable. 

Let’s begin with our discussion. 

• Choosing The Right Core Bit

Every type of rock will call for a particular kind of matrix. And, again every matrix is made up of alloying elements, metallic powder and diamonds. The hardness of the matrix and how many diamonds are used, both of these factors determine the hardness of the rock. 

The drill matrices are developed to carry out a specific scale range ideally. So, you are required to choose a bit that effectively suits the hardness of the ground that is to be drilled. 

Harder ground requires a bit specifically with a higher number. It looks counterintuitive, but hard rock requires a softer matrix. A bit with a higher number possesses a softer matrix, exposing diamonds well. 

Now, the exposed diamonds can cut the rock much better. Therefore, the diamond drill bits are perfect for drilling holes through rigid materials like gemstones, stone, rock, minerals, glass, shells, and a lot more.   

• Watch Your Diamonds

It becomes essential to avoid overexposing your diamonds when drilling in hard ground. There is a high risk of having them break or pop-off in this case. For avoiding this particular problem, you should necessarily pay attention to your drilling parameters. Your main goal should be to play around with them. 

It would help if you were careful about the ratio where you are advancing and getting the best penetration rate possible, especially with the least amount of feed pressure. Generally, there is an increased risk of burning the bit if you fail to maintain enough water flow. 

On the other hand, if the water flow is more than required, then there are chances that it can keep the bit from sharpening. Too high rotation speed can polish the diamonds, whereas too low rotation speed can lead to excessive wear on the matrix. 

Even in some worst circumstances, you can end up polishing the diamonds. But, if this type of situation occurs, you can sharpen those. However, if the diamonds break off, then the life of your bit will also be reduced as you will have lost matrix height.  

• Frequently Have A Check On Your Core Lifters

It becomes challenging for the core lifters to operate in hard ground formations. There are chances for tearing the core lifter springs more quickly if the ground is silicified and hard. The spring now has to perform more work for breaking the core. 

So, it is suggested that you effectively check those after every run. One of the best ways involves wetting a core piece and positioning it into the end portion of the core case. By adopting this particular approach, you would be able to check whether it is functioning correctly or not. Always ensure that the wet piece of core does not slip. 

Final Thoughts

While drilling in hard ground, the most significant decision always involves choosing the perfect core bit. So, you should essentially consider all of the tips mentioned above to make your job of drilling through hard rock much easier. But, you should also have a close look at other variables like variability and abrasiveness. 

We hope you have found this guide to be very helpful and informative. Are you looking forward to opting for diamond drilling services in london? If yes, contact CA Drillers today to get in touch with our professional and skilled drilling specialists.