Concrete Cutting: An Insight To Concrete Core Drills and
Concrete Core Drilling
Concrete core drilling is the process of drilling perfectly
round holes through concrete walls, floors and other concrete
structures. Concrete core drilling is the most commonly
recognized use of any diamond concrete cutting tool. Concrete
core drills or "core rigs" can be operated in any orientation,
vertical, horizontal and even upside down thru concrete
ceilings. A concrete core drill bit consists of a steel tube
with diamond segments brazed or laser welded on the drilling
end. The core bits are mounted on the rotating shaft of various
types of concrete core drilling machines. Most concrete core
drills are connected to a stand that is secured to a wall or
floor with a concrete anchor and a bolt but there are also
concrete core drills that use vacuum pressure to attach to a
floor. There are also many different types of "hand held" core
drills. Concrete core drills can be powered by electricity,
hydraulic, gasoline or air power sources. Concrete core drill
bits can range in diameter from 1/2 inch to 72 inches in
diameter and drilling depths are virtually unlimited with the
use of extensions. A solid cylindrical slug or "core" of
concrete is removed from the hole after the drilling is
complete. The applications for concrete core drilling are
virtually endless.
Core holes are used for "utility penetrations" such as
electrical, plumbing and heating but are also commonly used for
venting furnaces or clothes dryers. Concrete core drilling also
allows concrete structures to easily be made ready for sprinkler
systems, HVAC ducts, fiber optics, phone lines, computer lines
and much more. Core drilling methods are used widely in
underground utilities construction, most commonly, manhole taps,
underground vault taps, and wherever sewer, water, steam, air or
communication lines pass through a concrete or brick structure.
Line drilling or "line coring" is similar to perforating, when
core holes are drilled in a series of overlapping holes in a
row, allowing for one large piece of concrete to be removed.
Line coring is an effective method for cutting and removing
small, square or rectangle openings of almost any thickness of
concrete where other concrete sawing or cutting methods cannot
be applied.
Although not recommended, concrete core drilling can be
performed by an advanced "do it yourselfer" and the equipment
necessary to perform concrete core drilling is readily available
at your local tool rental and supply store. Most professional
concrete cutting companies have a minimum charge of $250 to core
a hole for you and it can take a professional as little as 10
minutes to unload his equipment, core the hole, and reload his
equipment. Yet, I have seen homeowners rent the equipment and
spend an entire weekend trying to core a single hole and then
call a professional concrete cutter in to complete the project
anyways. Just like with any trade a professional concrete cutter
will make his job look easy.