Core Drilling Guide: Introduction to Core Drilling
Are you ready to obtain the best drilling results for your project? If so, you need to determine what kinds of diamond bits or drills are perfect for the job. This is important since knowing the right tools to use will save you both time and money.
To which category do you belong? Are you a novice, an experienced engineer, hobby enthusiast, researcher, or a contractor? Knowing this will help narrow down your choice to the types of diamond bits that are most appropriate for completing your project.
To ensure that everything goes smoothly, take heed of these three prerequisites to core drilling success:
- Proper detailing
- Suitable preparation
- Following basic techniques
Type of Material
What kind of material are you working with in your core-drilling project? What are its features or characteristics? This will help in determining the tools and techniques you’ll need to obtain the desired outcome.
The kind of material you are planning to drill is an important consideration in your choice of drills:
a) Hardness of Material
For ultra-hard Alumina, Sapphire, natural/precious stones, materials with high metal content and advanced ceramic; metal bonded sintered diamond drills are the best.
For less expensive or softer materials such as tile, soft stones, glass, and composites, nickel bonded electroplated diamond drills work the best.
The basic rule for core drilling is that you will require soft bonds for hard materials, for free and fast drilling. Similarly, abrasive or softer materials require hard bonds for long-lasting performance.
b) Cost of Material
What kind of material are you going to drill? Determine how expensive it is. For expensive or precious material, the cost of the bit or drill matters little.
The use of a diamond thin wall core drill will help minimize deformation and loss of material. Having an estimate related to per-hole quality and target cost surely helps.
c) Density & Geometry of Material
Each type of material has a specific composition, density, and hardness. A method or technique that works for one, may not work for the other.
If you are looking for optimal, consider custom diamond drills that suit perfectly the type of material you’re planning to drill.
Material properties such as brittleness, size, shape, hardness, and diameter, will help in your choice of bits, clamping methods, feeds, speeds, and drilling equipment.
d) Thickness of Material
The thickness of the material you’re drilling determines how much pressure and coolant to use.
Multiple direction coolant works the best with through the drill, coolant submerged drill, and from the sides. This ensures enough lubrication and coolant will reach the drilling zone.
Running the coolant at high pressure through the diamond bit/drill centre using a swivel water adapter is ideal for drilling a material thicker than 1 inch or 25.4 mm. With, long-depth drilling you will require a stepwise mechanism using multiple bits or drills.
Five Essential Tips For Core Drilling
It is recommended to hire professional concrete drilling or sawing company for core drilling or concrete cutting tasks. Hence, if you wish to give a try on your own, here are some tips to help you to become the best choices available and ensure the success of your core-drilling project.
Choose the Right Drill Machine
There are different kinds of drill machines available for use on concrete. You may choose to either rent them or purchase them for good. Core handheld drills allow the creation of holes, which are up to a diameter of 3 inches. However, for successful spring testing of concrete you need to drill a hole, which is at least 3.7 inches in diameter. For this reason, you will need to use rig-mounted or drill stand units. For those who are considering the purchase of such units it is necessary to go for multi-function purposes. This way you can ensure the best value for the money spent. You can use them for dowel-hole drilling or electric/plumbing holes.
Find Suitable Stand Attachment
Based on where you need to drill holes specific stands are required. For example, for doing it on slabs having flat surfaces just use vacuum stands that use suction power to keep it attached to the floor. In such cases, you do not need to drill anchor holes. For core drilling in the walls, securing the stand on it is necessary. Presence of safety chains with stands prevent accidental slipping.
Consider Your Power Options
For powering the core drill one can go for one of the three available options. This includes electric, hydraulic, and air-powered sources. The work environment along with the availability of power on the job-site determines the type of source ideal for your requirements. Units available in the market allow appropriate speed choices related to concrete hardness and hole-size.
Consider the Drill Depth
Regular core drilling requirements can be dealt with successfully using simple 1-foot long bits. For drilling requirements higher than this, utilization of barrel bits will do quite well. The barrel bits are bit extensions allowing deeper core drilling compared to the size of existing cutting bits. You can move to increased depths based on requirements, using such drilling extensions. Consider the type of extension you may require for getting the best results in specific scenarios.
Choosing a Diamond Bit
For choosing the appropriate core diamond bit, users need to consider the aggregate hardness and psi of the concrete surface to be used for drilling purposes. In to get the best effects the core diamond bit needs to be in complete proportion to the drilling material or surface. The basic rule of thumb is that construction workers should use a soft diamond bond for core drilling on hard surfaces or materials. Similarly, they should use a hard diamond bond for core drilling on soft surfaces or materials. There is no single solution available that affects all and one needs to consider their choices based on the current situation and drilling require for ensuring project success.
Core Drilling Techniques, Applications and Available Tools
If you want a perfect round shaped hole in a horizontal or vertical concrete object, then core drilling is the way to go. Core drilling is a process of using core drills to cut holes in any concrete surface. If you want the same thing done on a construction site, then you first need to know how it can help you.
There are different types of methods and tools that are used for core drilling. The concrete surfaces are hard and drilling in them requires power. However, cutting perfect holes on the surface is even harder, provided you follow a correct method. This is where the core drilling can help. Once the drilling process is done, the concrete can be removed from the wall to get the perfect holes. To remove large amounts of concrete from solid objects, core drilling is used to create multiple holes in the surface first and then the concrete is removed. There are many different uses of core drilling.
The drilling is needed for setting up heating facilities, plumbing, electric lines, and a lot more. The core drilling techniques are used to create the different sizes of holes in the concrete walls of buildings, as per the need. It is readily availed for all kinds of underground works, too. Installation of phone lines, water pipes, and drain lines; these chores require heavy amounts of core drilling. This is why construction workers rely only on the best tools and equipment for any core drilling job requires holes with a diameter of 1-2 meter to get accurate results.
Depending on the job type and the required results, different techniques of core drilling are used by the workers. Rotary core drilling is one of the most commonly used methods. It’s needed to make perfect holes in rocks and concretes. There are both dry and wet drilling methods that are used according to the surface. The hydraulic and electric core drilling methods are commonly used in construction sites. The hydraulic method is used when large and deep holes are needed in a concrete surface. The electric core drilling is mainly used for setting up electric lines, plumbing, and gas lines.
The hand held and mounted drills are the primary types of core drilling tools. Other tool types include mini electric drills and large electric drills. The mini hand held core drilling tool is perfect for small projects like installing a cable inside a house or office. However, for larger holes, mounted drills are used. A professional core drilling service offers tailor-made solutions to a wide ranging drilling need.
What Is The Procedure For Concrete Core Drilling?
Are you in the concrete cutting industry? Do you want to learn about procedures for concrete core drilling? If so, please keep reading for more information.
Core drilling is an essential task for virtually all concrete structures at some point.
Whether you want to pull a sample of concrete for testing purposes, drill an opening for manholes or install electrical and plumbing lines, core drilling is important.
Core drilling should be performed only by highly skilled and experienced concrete cutting technicians. Such technicians can provide safe and quality work.
In this article, we will take a look at the following:
- Basics Of Concrete Core Drilling
- Concrete Drill Types
- Choosing The Best Concrete Drilling Service
Basics Of Concrete Core Drilling
Concrete drilling is a specialised service offered by concrete cutting companies. A cylinder of concrete material or a core is removed with a concrete drill.
Diamond core drills are the most effective tools to use when core drilling concrete. Core drilling is common when installing common utilities such as:
- Recessed lighting and fixtures
- Cutting walls, floor slabs, and ceilings for plumbing, HVAC, cabling, electrical, and communication services
- Analyse concrete samples
- Roadway holes for doweling drilling, drainage, or rebar tie-ins
The concrete cutting technician will use a small threaded anchor to secure the drill post to the wall or concrete slab. He will then bolt the drill post – which acts as a guide for the core drilling process.
This will let the drill hit its mark straight on and make a consistent and smooth core. Once the drill post is fastened, the technician will mount the drill bit.
The drill bit will depend on the size the client specifies. Once the drill bit is mounted, the drill is turned on. Water will be applied as a coolant while pressure is placed on the crank.
The core drill has a hand crank to drive the drill to the surface and cut through the concrete. Once the surface is penetrated, the core will come out with the bit.
You can pull out the core manually if it is found in a slab.
Concrete Drill Types
There are two types of core drills such as impact and non-impact core drills. Impact drills have two sub-types such as hammer drills and rotary hammers.
A hammer drill is a small tool equipped with a bit that drills into the concrete. The hammer drill has a ramped ratchet system with a high-speed vibration or rattling action.
Regular bits are not the best to use with hammer drills because they can easily break under repeated impact conditions.
Even though rotary drills are similar to hammer drills, they are more efficient. A rotary drill can drill up to 100mm diameter. A hammer drill can only drill up to 12mm compared to a rotary drill.
You need a non-impact drill if you want to drill larger holes – up to 250mm. A non-impact drill has diamond teeth.
Because these drills don’t impact the drilling surface, the drill bit needs to be exceptionally strong. Drilling with a diamond-embedded drill is quite complex.
Frictional grinding can generate a lot of heat in the process. That’s why you need a professional concrete cutting service to perform such tasks.
Concrete Coring Allows the Creation of Precisely Positioned Openings in Concrete Structures
Core cutting or concrete coring is the process of drilling a large hole in concrete.
With this, you can make precisely dimensioned holes in concrete walls, floors or slabs or any other structure that requires the creation of such an opening.
Most concrete cutting companies offer this as a basic service and will have the specialized diamond tipped core cutters that can easily undertake such jobs.
Once the concrete has been laid it is necessary to create circular openings so that there are spaces for ducts, cables and other utilities. These will be used in the installation of phone lines, plumbing, and electrical wiring. Openings are also required to create ducts from climate control or other needs.
These needed spaces can be made without compromising the structure itself. Drilling can be done on any hard surface, not necessarily concrete, and to any required depth. Core drilling can make holes from three-fourths of an inch, up to about six feet in diameter. Depths can reach sixty feet.
When a hole is made, a solid core is removed from the structure.
This shows that the concrete does not get pulverised and the hole is made neatly. This undisturbed core of concrete has also been used by engineers to test the strength and soundness of any concrete structure.
These cutters are made from high strength steel that has carbide or diamond tips along the circular edges of a hollow or tubular drill bit. The drill bit to be used depends on the size of the hole you need.
Core drilling machines require a lot of power and most of the equipment uses electricity, hydraulic or air compressors. Machines that have adjustable speeds are the most versatile and make the work that much simpler and easier.
You can get equipment that is mounted on stands and may use a vacuum to grip a floor and retain the drill in position. If the drilling has to be done in walls, you need to secure the drilling stand with proper anchors that can take the strain of the equipment and drilling vibrations.
The spot where you require the opening must be clearly marked so that you will not hit rebars or conduits within the concrete.
Start drilling slowly without exerting any pressure so that the drill bit cuts the path you require it to follow. Once this is correctly determined, you can increase pressure and increase the speed of drilling.
You should check the correctness of the alignment at various intervals till the final depth is reached. If you have to drill through the thickness of the concrete the core will come out along with the drill bit. You may require a hammer or other means to remove the core from the drill bit.
How Core Drilling Can Save Time And Money On A Retrofitting Project
Due to the changing economic climate, there are plenty of older, well-built concrete buildings that are being retrofitted and repurposed into other types of uses. In older industrial parts of the city, old structures are converted to loft apartments, small retail businesses, and restaurants.
Doing these involves a lot of concrete core drilling, so that plumbing, electrical, and IT conduits can be installed. Let’s take a quick look at how this type of drilling can make working on concrete structures easier.
Most Older Warehouses And Manufacturing Facilities Are Shut Down
In many old cities, there are large sections that have been vacant, left in the aftermath of manufacturers relocating to other countries.
Good thing there are plenty of new companies that would like to get prime downtown locations that would love to move into the neighborhood. This has created a demand for retrofitting the older buildings into modern offices, lofts, artist studios, online offices, and restaurants.
For this to work, each small section of the building should have bathrooms, kitchens, plumbing and wiring and compliant to existing laws. This is where concrete drilling comes in. It allows pipes and electrical cables and conduits to run into every part of the building.
In concrete drilling, a diamond-tipped hole saw is used to make round holes of several different sizes to accommodate each type of access. Of course, an architectural plan will have to be made, approved by the local inspector, and then followed to the letter.
Core Drilling Can Also Be A Lifesaver In Removing Sections Of Concrete
This is also needed when you’re turning an old warehouse into a couple of townhouse apartments. Several staircases will have to be retrofitted into the structure.
One of the best uses of core drilling is to make core line holes in the thick concrete floor between levels and then connect the dots to remove a large portion of concrete. This makes concrete removal easier. Even with space limitations, the core driller has enough room to maneuver.
Another advantage of using diamond core drilling apparatus is that it makes precise cuts, making the job dust-free. With this, the activity won’t disrupt activities in an office or even a restaurant.
Basic Safety When Working With Core Drills
Always wear eye and hearing protection! Wear respiratory mask for dry cutting! Consider using a PAPR (powered air purifying respirator). For more info on silica, see OSHA’s info.
Careless or improper use of a diamond core drills could cause personal injury!
- Do not use any tools if damage is suspected.
- Beware of sun damage to the operator
- Have a fire extinguisher and first aid kit nearby
- Use a barrel that is suitable for the machine and the material to be cut.
- Check for suitability before cutting dry, and take extra precautions because of the dust
- Check barrel for damage before installing.
- Check machine condition before performing any cutting operations.
- Check for a tight fit to the shaft of the drill.
- Check condition of barrel regularly.
- Check all electrical cords and plugs (if applicable) and protect them from water.
- If you are drilling dry, always be aware of the danger of breathing in the dust. Ensure a dust extraction system is used with a suitable filter fitted. Use a half face respirator or a PAPR (Powered air purifying respirator).
- If you are drilling wet, the slurry created can dry out and create a hazard for other users – dispose of slurry as per your local regulations.