What Is Core Drilling?

Concrete drilling, or core drilling, is used every day on construction and engineering projects around the world. Bridges, dams, telecommunications lines, rehab projects, sewer tunnels–these are just some of the many places you’ll find concrete drilling used.

Though the projects themselves are big news, you seldom hear specifically about the techniques used that made it a success. Cobra Concrete Cutting Services Co. is one of the premiere companies in Chicago’s concrete drilling industry. Of course it’s important to have the right equipment to accomplish the drilling that’s needed. Many companies have the drilling equipment that’s needed, but not every operator is fully experienced or prepared to use their equipment safely and effectively to achieve the desired effect.

Diamond coring techniques create a precise circular penetration to the concrete. These holes are anywhere from 1/2″ to around 60″ in diameter, and can be created in any type of concrete slab or wall, at any angle.

Some of the things that the drilling operator has to understand about the core drilling process include:

When drilling with a wet core bit, the correct amount of water needed is a key element determined by the operator’s experience. More water is not necessarily always better. The purpose of the water is to create a concrete slurry from the dust that drilling creates. If there is too much water, it simply washes the dust away. If there is too little, the bit continues grinding the same particles and is less effective. In either case no slurry is created and the result suffers. The slurry also serves to cool the diamond drill bit.

The drilling rig must be anchored properly in order to insure a straight core. If the rig is not anchored properly, it is difficult to produce the hole that’s needed with any degree of precision. In addition, there are safety issues involved with improperly anchoring the rig.

Setting the motor to the proper revolutions per minute is very important to success in diamond core drilling, as it determines whether the diamond surface is grinding correctly. Every core bit is run at its optimal speed, with smaller bits generally requiring higher speeds.

To maintain the correct drill speed, the power supply must be adequate and consistent. Most core drilling machines are electrically powered, although hydraulic is available for large diameter holes. Operators try to run the motor near its maximum rated amperage, but without exceeding it, which might cause the drill motor to overheat.

Another use for core drilling is concrete sampling analysis. This technique can assess the strength of concrete, frequently to determine whether it needs repair and reconstructive work. Cylindrical specimens of specific depth obtained with core diamond drilling are then prepared and tested by a lab. The results determine the concrete’s density and strength, its water and gas permeability, and a variety of other factors.

Whatever project you are working on, whether plumbing, electric, HVAC , or sample analysis, you can rely on the experience and training of Cobra Concrete Cutting to do the necessary concrete drilling effectively and safely. Please contact us to discuss the ways we can put our expertise to work for you.