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Core Drilling
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Typical Applications:
• Floor
and sewer drains
• Sewer tie-ins
• HVAC openings
• Plumbing and electrical lines |
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Core
drilling techniques are used when precise, circular cuts
are needed. Holes of almost any diameter are easily
drilled to make openings for plumbing, electrical and
HVAC installations. Core drilling is also commonly used
to create holes for routing cables or placing anchoring
bolts, installing load carrying devices or dowel bars,
or for concrete sample analysis.
A 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 drilling machines. Core drills can be operated in any
orientation, vertical or horizontal. Core drill machines
can be powered by electric, hydraulic or air power
sources. Core drill bits can range in diameter from 1/2
- 60 inches (13 - 1524 mm) and drilling depths are
virtually unlimited with the barrel extensions.
Core
drilling played a major part in a hospital renovation in
Halifax, Florida. A CSDA contractor was hired to remove
a 20-foot by 20-foot by 4-foot (6.1 x 6.1 x 1.2 m) tower
crane footing that had been left behind when the
hospital was originally built. Three electric drills
were used to line drill 355 6-inch (152 mm) diameter
holes to a depth of 4-foot 6-inches (1.4 m). Line
drilling is a process whereby the holes are drilled one
next to another in a line. This process was used to
partition the footer into 4-foot by 4-foot by 4-foot
(61. x 61. x 61. m), 6-inch (152 mm) sections weighing
approximately 11,000 lb. each. A total of 355 holes were
drilled in 10 days. This project utilizing core drilling
allowed the renovation to be completed within budget;
allowed undisturbed use of the existing facilities; and
demonstrated the advantages of today's diamond tool
cutting techniques as used by a professional CSDA
cutting contractor.
(description of core
drilling partially provided by: Concrete Sawing &
Drilling Association) |
