How Concrete Core Drilling Works: Hole Sizes from 12 mm to 600 mm

How Concrete Core Drilling Works: 12 mm to 600 mm | Alpha Core Drill

Concrete core drilling makes clean, round holes through slabs, walls and beams for pipes, ducts, cables and structural testing. Unlike a hammer drill, it cuts a neat cylinder and leaves the surrounding concrete intact. Here is how the process works and what to know before you book it.

What core drilling is

A core drill uses a hollow cylindrical bit set with industrial diamond segments. As the bit rotates, it cuts a ring into the concrete and leaves a solid cylinder, the core, in the middle. The core is then lifted out, which gives a smooth-sided hole with little damage around it.

Alpha Core Drill offers coring diameters from 12 mm to 600 mm.

The process step by step

1. Scan. GPR scanning locates rebar, post-tension cables and conduits so the hole can be placed safely.
2. Mark. The position and diameter of each hole are marked on the surface.
3. Secure the rig. For larger holes the drill is fixed to the slab or wall so it stays steady and cuts straight. Smaller holes can sometimes be drilled with a hand-held machine.
4. Drill with water. Water cools the diamond bit and carries away the fine slurry. It is collected and removed to keep the area clean.
5. Remove the core. Once the bit passes through, the core is freed and lifted out.
6. Clean up. The slurry is cleared and the opening is left ready for the next trade.

Choosing the hole size

The right diameter depends on what passes through the hole.

• Small holes suit anchors, cables and small conduits.
• Medium holes suit pipes, drains and ventilation sleeves.
• Large holes, up to 600 mm, suit big ducts and service openings.

Tell us what is going through the opening, and give us the exact outside diameter, including any sleeve or insulation. We can then confirm the bit size that leaves a suitable fit.

Why scanning comes first

A core bit cuts through steel as well as concrete. Without a scan, it can hit reinforcement, a post-tension cable or an embedded conduit. Reinforcement can sometimes be avoided by moving the hole a few centimeters, but a damaged post-tension cable is a far more serious matter. Scanning shows where the safe positions are.

Coring or saw cutting?

Coring is the right choice for round holes. For rectangular openings such as doors and windows, or for cutting slabs and walls into sections, wall saw or floor saw cutting is the better method. See our concrete cutting service for those jobs.

Before you book

Have ready the number of holes, their diameters, the thickness of the concrete, and what lies on the other side. With these details we can plan the work and the clean-up.

Alpha Core Drill provides concrete core drilling and GPR scanning across Dubai, Abu Dhabi, Sharjah and Ajman. Contact us for a quote.