Concrete Drilling Basics – A close look
Concrete drilling is an arduous task. If done incorrectly, it can even become downright dangerous. Here we take a close look at some key concrete drilling basics.
What Is Concrete Drilling?
As concrete is a far hardier building material than most others (for example: plasterboard or wood), drilling into it is not an easy task. When used on concrete, a regular steel drill bit will not be able to penetrate neatly and effectively into it. That’s the reason concrete drills are equipped with diamond bits.
Concrete Drill Types
Concrete drills are of two types – impact drills and non-impact drills. There are two further sub-types of impact drills – hammer drills and rotary hammers.
The regular hammer drill is quite small and is equipped with a bit that drills into concrete and simultaneously also gets pushed into it. To speed up drilling, hammer drills employ a ramped ratchet system high speed vibration or rattling action to the three jaw chuck. You cannot use regular bits in a hammer drill for concrete drilling as these will break under the condition of repeated impact.
Rotary hammers are much the same as hammer drills; only more efficient. A rotary hammer can drill holes of up to 100mm diameter. Standard hammer drills on the other hand can drill only up to 12mm. In contrast to regular hammer drills, rotary hammers employ piston/crankshaft assembly that beats on the end of the bit that slides freely inside the tool holder, and keeps turning and hammering back and forth.
If you are looking to drill larger holes (250mm or more in diameter), you require a non-impact drill that is equipped with diamond embedded teeth. These drills do not put impact on the surface undergoing drilling and hence the drill bits have to be exceptionally strong. On the flip side, you require a big rig, loads of setup work and long drilling time.
When required, a vacuum pump sucks the drill down to the floor and hence requires smooth and crack-free surfaces. If your surface is otherwise, you need a different setup.
Drilling using a diamond embedded bit is complex and requires frictional grinding of concrete that generates high amount of heat. The drill bit has to be kept cool as otherwise overheating of the matrix with embedded diamonds makes it glazed and unsuitable for drilling. This cooling is done by a constant and high pressure running stream of water that mixes into concrete dust being generated and requires vacuum cleaning of the resultant slurry.
Diamond drill bits can drill for about 16 inches per pass. After which the core plug has to be taken out, extension to the stump has to be added and then the drilling can progress further. Using this process, drilling of very deep holes is possible but as that falls outside the purview of concrete drilling basics, we will skip it.
These are only a few key concrete drilling basics. The drill operator must also be qualified to use the machinery as per the instruction manual, wear the prescribed protective gear and take due care of the drilling tools.
The two key caution areas to focus on are choosing unsuitable drill bits or letting the drills overheat, otherwise your equipment can suffer serious damage. Take time to choose the optimal parts and follow all prescribed guidelines to get your concrete drilling job done correctly and smoothly. Remember, mistakes can be expensive, grossly inconvenient and even potentially dangerous.
For that reason, we recommend using concrete drilling professionals to complete the job. Please call Auscut on 1800 AUSCUT for an obligation-free quote on your next concrete drilling project.