How to Use a Concrete Drill Bit
Overhaul, laying of communications during the construction of concrete buildings need an effective drilling tool. The work may involve through drilling of thick monolithic walls for laying pipes, cables, or it may be necessary to make a recess for the socket, switch. The right choice of the drilling tool of the right diameter for concrete will ensure the quality of work, drilling performance and the longevity of the crowns.
Inside hollowing equipment for drilling and drilling (through and through) concrete is designed for excavation of material of any strength from monolithic structures, which allows you to create technological holes of large and small diameters. And also to solve everyday problems, for example, to prepare places for the installation of socket boxes for electric networks. Crowns greatly accelerate and simplify these operations, ensuring accuracy and accuracy.
A crown on concrete is a piece of metal pipe made of tool steel, on the end edge of which there are cutting elements of high strength, and on the other end there is a shank (flange) for mechanical fastening in the rotation drive clamp. The crown is a prefab or a single design. The heads of the products have a wide range of diameters and lengths, in a number of modifications in the center there is a centering interchangeable drill with a carbide tip. In the cup (cylinder) on the sides there may be cavities for removing dust and materials from the drilling zone. Drives for such a tool. perforators, drilling machines, drills, impact drills, etc.
Crowns on concrete differ primarily in the material mounted on the cutting edge of the cup. It is he who sets the tool durability, productivity and quality of work. Hard metal alloys, tungsten carbide alloys, diamond chips are installed in cutting crowns.
Also, the material of construction of the working part of the cup determines the drilling method. Impactless is used for carbide-tungsten and diamond crowns, impact. for carbide (gear). Methods of cooling the working part. water (wet) and air (dry). In both versions, the device can make holes for the socket.
From hard alloys
They are used for percussion drilling with a hole puncher in concrete to the level of metal reinforcement or without it. The cylindrical fixture is equipped with a cutting edge consisting of soldered carbide working teeth. The cup is attached to the rotary drive using shanks: SDS max, SDS, SDS.
Products are widely used for household drilling of a small number of holes with a diameter of 20. 100 mm (including a diameter of 70 mm for sockets). The resource of the heads (without the possibility of recovery) reduces the intensive shock load of the drive, which also negatively affects concrete structures.
This is the modern most technologically advanced and effective tool for drilling holes in concrete. Diamond concrete crowns are equipped with soldered wide cutting segments (solid cutting surface) with diamond (corundum) abrasive. They are used for drilling reinforced concrete using the shockless method, which protects the supporting structural elements.
Cutting ring spraying is also used for drilling, for example, tiles, ceramic tiles, which requires subtlety in work. The tool has a significant resource (worn edges are subject to restoration), which increases its economic efficiency. The surface of the holes has predetermined dimensions, smooth walls, since the concrete is crushed with a crown with ultra-strong tiny crystals, and not cut.
Video: How to Use a Concrete Drill Bit
Types and characteristics
Crowns with a diamond cutting edge are distinguished by diameter, design of the connection with the drive, cylinder length, type of cutting segments, method of use and method of operation of the drive mechanism. Working segments with a soft matrix (marking "M") in the crown are used on especially strong concrete. They are easily self-cleaning from clogging with drilling products. On ordinary reinforced concrete, bundles of medium hard diamonds are used (marking “C”).
Segments with solid matrices (type “T”) are used at reduced speeds, including on high-quality concrete. There are products with different frequency of segments and a continuous ring of diamond crystals. All nozzles are used for wet and dry drilling. However, the KS crown (“C” matrix) is structurally different in that it has special-shaped cavities on the cylinder that contribute to air cooling.
A concrete crown with a diamond cutting surface is used in shock-free mode, which makes it easy to pass reinforcement. Drilling machines have many standards for fixing crowns on the shaft. They differ in size, design, ways of attaching the shank (BSP, SDS, thread). It is important that the shank (with adapter) matches the clamp of the drilling machine. According to the outer diameter, the cups are classified into: small (up to 1.2 cm), medium ones. 3.5. 8.2 cm (used to form holes for socket boxes. 70 mm), large. with a diameter of 15 to 40 cm and especially large. 40. 120 cm.
The design of the heads depending on the diameter may contain a different number of working segments. For example, a cylinder with a diameter of 4.6 cm has 5 cutting elements, and a product with a diameter of 65 cm has 32 segments. The length of the fixture pipe characterizes the working depth of drilling through holes in structures of various thicknesses. The length of the passage of concrete material is up to 500 cm. Such products have a significant resource, for example, a cylinder with a diameter of 20 cm with high-quality diamond cutting segments passes up to 20 m / pog. medium reinforced concrete.
Principle of operation
Concrete work involves the use of a hammer drill in shock-free mode. The machine is fixed on anchors, which ensures the accuracy of the drilling direction, eliminates distortions and jamming of the cylinder in the hole. This feature reduces noise and dust. However, accurate use of a hand tool is also possible, for example, when drilling recesses with a diameter of 70 and 100 mm for socket boxes. The crown is installed and fixed in the drive lock.
In the process, it destroys the material only under a thin diamond cutting surface, and at the end of through drilling, a stone cylinder remains in it. The best option is to drill with a flow of running water that protects the cutting edge from overheating, eliminating sludge and dust. An alternative would be to use cylinders designed for air cooling.
The market is filled with crowns that have various features and advantages. BOSCH is a high-precision, durable, professional product with universal adapters. CEDIMA. products effectively pass concrete up to 5 m thick. AEG. products with universal adapters that provide quick replacement and are compatible with other equipment. Reliably works at a speed of 8000 rpm.
Tyrolit. Offers a wide range of hollow drills. Rothenberger. produces diamond crowns and components in cooperation with leading enterprises. High quality products are also provided by Adele, SPLITSTONE, Alaton, EuroPrice. Niborite, etc.
Only reliably work with unreinforced concrete. Products are also well suited for drilling tiles. The drive can be a drill with a capacity of 800 watts, in which a special 6-sided shank of the cup is fixed. Suitable for drilling holes for socket boxes (a plastic product into which sockets are installed) with a diameter of 100 and 70 mm.
How to choose a crown size?
The choice is based on a preliminary determination of the hardness of concrete (reinforcement), the drilling method (dry or wet), hole diameters, based on the sizes of pipes, sockets, cable thickness, etc. For example, for a set, a socket (switch) is a sock (6.8 and 10 cm) the crown should be chosen with a diameter of 2. 3 mm more so that the gypsum mortar well strengthened the base in the wall. An important factor is the power, type of drilling machine, its compatibility with the tool. Cups with a diameter of up to 25 cm work well on drilling devices with a power of about 1 kW. However, it is advisable to avoid the use of adapters, since a low-power drill can fail due to the use of a larger diameter crown.
How to use?
Work is carried out in compliance with safety and electrical safety rules in protective equipment. The correct and reliable assembly of the crown is checked. The machine is exposed and fixedly mounted or a manual punching device is used. The equipment is guided exactly along the axis of the planned passage of the hole. First, a centering drill works according to the marking, and then a cylinder cup is completely immersed in concrete without effort.
If necessary, allow the cutting cup to cool. Upon completion, the drilled material is removed from the hole. A correctly selected crown allows you to easily, quickly and accurately make a hole of the desired diameter even in the most durable concrete structure.