If you need to secure or hang something heavy and massive, then it’s impossible to think of a better option than an anchor bolt. Have you seen all those fiber optic wires running between buildings? They are quite heavy. It is the anchors that hold this entire web.
An anchor bolt is optimal under two conditions. Firstly, if you plan to hang a heavy load. Secondly, the material of the attachment point is dense and hard. Yes, such fasteners are not suitable for fragile surfaces. Its main area of application is concrete, natural stone and solid brick. In our article we will talk in detail about the types of popular anchor bolts, define their purpose, installation methods and design.
There are enough types of anchor bolts to surprise the average person. This is quite fair. Each fastener was created for a specific type of cargo and the nuances of its fastening. There are even hardware that are only used for certain things. Let's look at the most basic ones.
Anchor fastening types and features of anchors application tightening technique
Using a kit for fastening to anchor supports, it is possible to install the coupling on power transmission line supports and wind the free length of the optical cable onto the frame.
This type of connection is used to ensure the safety of work performed at height according to the permit. To carry out such activities, a permit is required, issued by a labor protection specialist and endorsed by officials from among the managers, and the work itself is carried out by a group of workers under the guidance of foremen and supervisors. The most widely used are anchor bolts that have a spacer operating principle based on the expansion of the rear section of the sleeve when a cone-shaped sleeve is screwed into it. Among the well-known types of anchors, experts call driven, expanding, chemical, expansion and wedge structures. Each of them ensures reliable retention of the fastening part due to the use of the friction force between the contact surfaces of the bolt and the installation area, the thrust force, which ensures compensation of the effective stress by the resistance of the metal of the product. Increasing the diameter of the spacer sleeve when screwing a bolt into it ensures a reliable connection due to the combined action of thrust and friction forces.
Experts emphasize the importance of choosing the right type of anchor, based on studying the manufacturer’s documents that determine the specifics of each type of product. since the reliability of the system largely depends on the building material used at the point where the bolt is attached. Proper execution of fastening is necessary to prevent damage during operation of the parts that make up the connection and to ensure comfortable work in the support. Such a connection will ensure safety when working at heights, fastening heavy static (horizontal bars) and dynamic (diamond drilling rigs) structures.
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General characteristics
Anchors (anchor-type fastenings) are needed for permanent installation in dense, hard, brittle and porous bases. They are used to hang heavy pieces of furniture or equipment, fix massive structures on floors, ceilings and walls with a mineral composition (bricks, concrete, foam blocks, etc.). In reality, this is a fastening that is more durable and is a reliable alternative to nails and screws. The material for creating anchors can be adhesive mass, polyamide, hard plastic or metal alloy:
Brass or aluminum with zinc for use in the domestic sector.- Carbon or structural steel for increased load and joint strength.
- Alloy or corrosion-resistant steel with high moisture resistance can also withstand heavy loads.
The operating principle of all kinds of anchors is based on the physical phenomenon:
- Crumple and fracture resistance.
- Friction force.
- Voltage compensation.
The consequences of incorrect installation of the fastener or exceeding the permissible load on the fastener can be very different:
- Tearing out a section of the base or anchor, which is used for its immersion.
- The shape or integrity of the body or bolt is damaged.
- The fastening is destroyed due to overheating or corrosion (burnout or melting).
In order for the “anchor” to work according to the stated scheme, the fastening element must be equipped with an internal thread for bolting. As a result, as it advances, the functional body will expand in the middle or at the end. The chemical group of products will work somewhat differently, and we suggest looking at the types of anchors in more detail.
What is an anchor
Initially, this is the name given to the type of fastener that is held in the mounting hole due to the expansion (wedging) of a special element (spacer sleeve or sleeve). The powerful friction forces that arise prevent the fastener from being removed from the mounting socket. This is the so-called mechanical anchor.
Now there is another type of anchor - chemical. It is attached using an adhesive composition made on the basis of synthetic resin. The mounting hole is filled with this composition, then one or another fastener is screwed into it: a bolt, a pin or fittings. Obviously, using “chemistry” we have a wider selection of fasteners.
Making an anchor
In the elongated nut, use a grinder to make a longitudinal cut about 2/3 of the length. Drill two holes from the side of the cut.
It will also be necessary to drill a hole of the same diameter in the “tongue”.
Using a steel pin, we connect both parts of the homemade product together. The edges of the pin are fixed by welding (or can be riveted).
We put a metal washer on the hook bolt and screw on the nut. Screw it into the extended nut. The homemade anchor is ready.
Working principle and application
Concrete is a porous material with a heterogeneous structure. At the attachment point, forces are created - pullout, compression, shear, shear, bending, twisting, which the anchor perceives together with the supporting structure.
Three operating principles are used:
- When the surface of the bolt interacts with the base material, frictional forces arise. The expansion is created by metal collets and dowels.
- At the anchorage depth, the material resists crushing or fracture. This is facilitated by collet bushings on the fasteners, extensions, and the curved shape of the rod.
Effective loads are compensated by tangential stresses at the point of contact between the monolith and the metal rod during gluing or embedding. Adhesive anchors and smooth embedded parts work on this principle.
If the fasteners are selected incorrectly, damage to the structural material, the body of the anchor, or its tearing, bending, melting, burnout, and corrosion may occur. The consequences of this can be catastrophic - collapse of roofs, facades, walls or fences.
Improper design, fastening and operation of anchors in bridges, dams or overpasses leads to emergency situations. But even an unexpected fall of a book shelf, curtain rod or TV is not the most pleasant event, fraught with injuries and material losses.
To prevent this from happening, anchors are designed to withstand loads. To design fasteners, use the Manual for SNiP 2.09.03, which contains a classification, calculation algorithm, recommendations for the formation and marking of wells, and installation of bolts.
Anchors perform a load-bearing or structural function. In the first case, this is a loaded mount, where the following is connected to the base:
- beams;
- floor slabs, balcony consoles;
- trusses, columns;
- elevators, flights of stairs and landings;
- wall or finishing panels;
- communications, engineering equipment;
- window or door frames;
- awnings, canopies;
- extensions;
- ceiling lamps, hoods;
- dropped ceilings.
Hardware is used for laying joists on concrete floors or slabs with voids. Installation of anchor bolts is used when attaching hanging furniture and electrical equipment to the wall.
Structural fasteners are used to prevent displacement of parts of the assembly, the stability of which is ensured by their own weight, as well as their straightening during construction.
No building is erected without anchors. They are installed before pouring concrete or after - in a prepared hole or finished well.
Types and methods of fastening
Anchoring is performed by various types of steel products, where one or several acting forces are used simultaneously - friction, thrust and intermolecular bonding during gluing.
Anchors are classified according to the following characteristics:
- purpose - foundation, ceiling, frame, universal;
- shape - straight or curved;
- design - solid or prefabricated;
- surface - smooth or threaded;
- contact area - for dense or porous material;
- installation method: hammering, screwing, gluing, through fastening.
Spacers
To solve critical problems, expansion anchors for concrete with nuts are used, where the friction force operates. They are a threaded stud with a conical tip and a sleeve. When screwed in, it wedges and firmly holds the bolt in the body of the concrete.
Advantages of these wedge fasteners:
- ease of installation of anchors in concrete;
- possibility of through installation;
- high load-bearing capacity.
Wedge hardware is used only for dense concrete. They need to be immersed deep enough and cannot be reused.
If a bracket is installed at the end of the rod instead of a nut, equipment can be suspended from such a mount.
Varieties of wedge anchors are sleeve or sleeve hardware. Available in the form of a bolt with a special wedging nut at the end or a stud with a conical widening. To ensure uniform distribution of internal stress, they are reinforced with double thrust.
These hardware are used in high and medium density concrete. A sufficient contact area with a small diameter of the rod allows it to withstand significant loads.
Drivers
For dense concrete, short drive-in anchors with metric threads and an internal cone are used. It wedges the base when screwing in a bolt or stud.
The mount is simply made and does not protrude to the surface. This option is used for installation of ceiling air ducts, ducts and other engineering equipment.
Hardware is hammered into the drilled hole, wedged with a center punch and a threaded rod of any length is screwed in.
Driven ones include a ceiling anchor or a dowel-nail, which is attached to the base through a part. This is a convenient connection for Armstrong ceilings, suspensions, slats, and mounting mortgages. Since the bolts are non-removable, they are often used as vandal-proof and fireproof fasteners.
Frame
Designed for securing window or door frames. The sleeve is cut along its entire length, and when tightened, a small wedging nut presses the structure against the opening to the desired position.
In the upper part of the sleeve, stops are located to protect against rotation and displacement around the axis.
Self-tapping screws for concrete
A strong connection is created by threads along the entire length of the hardware. When screwed into concrete, there is a high resistance to shear or pullout of the product. Thanks to this, the load-bearing capacity of the fastening is very high.
Concrete screws accept up to 100 kg of load, are easy to install and reliable in operation.
Expanding
These include the Molly bolt, commonly called a “butterfly”. Designed for mounting lamps, shelves, cornices, pictures in hollow concrete structures with low load-bearing capacity.
The collet on a bolt or screw is a drop-down skirt; when the rod is screwed in, it rests against the inside of the base cavity.
Special spikes on the outside of the collet go deep into the concrete and prevent the hardware from turning or moving during installation. The “butterfly” can be sold without a screw.
Chemical
A chemical anchor is a semi-liquid, quick-hardening mass with which studs or bolts are glued into the base.
The compositions provide a strong bond with concrete without point or local stresses. The load is evenly distributed along the length of the connection.
Important
Installing an anchor in concrete will be faster and easier if you follow a number of rules:
- Before installing the fasteners, you must correctly calculate the load. In ordinary concrete, the anchor can support up to 350 kg. And in cellular no more than 230. The diameter of the hardware can be from 8 to 24 millimeters, and it is selected depending on the load.
- The hole for fasteners must have smooth edges.
- The anchor is inserted as a whole and not in parts.
- The nut (bolt) is tightened clockwise.
Observe the correct selection of fasteners and follow these instructions, which will ensure reliable and long-term operation of the anchor installed in concrete.
With nut
The structural elements of this type of anchor bolt are:
- a threaded rod, one end of which is made in the shape of a cone, and a nut is screwed onto the other;
- a spacer screwed onto a stud (its lower end has longitudinal slots on the side surface, which form peculiar petals).
Anchor with nut suitable for through installation in a pre-drilled hole
Reliable fixation of such a fastening element is ensured due to the fact that the petals of the spacer sleeve are unclenched, which occurs when they are exposed to the conical end of the pin. In order for the tapered end of such a bolt to begin to enter the bushing and open its petals, a nut is used.
Mounting parameters of anchor with nut
Fasten an anchor bolt with a nut in the foundation or any other building structure made of concrete, performing the following steps:
- drill a hole, the diameter of which must correspond to the cross-sectional size of the spacer sleeve;
- thoroughly clean the mounting hole;
- carefully hammer in the anchor bolt and nut using a hammer;
- By tightening the nut, you achieve reliable fastening of the anchor.
After the installation of the anchor bolt is completed, you can unscrew the nut from the top of the stud and begin installing the required item.
Installation procedure for an anchor bolt with a nut
When choosing products of this type, you should keep in mind that they demonstrate their effectiveness only if they are mounted in durable and solid materials (concrete, brick, natural stone, etc.). Manufacturers, in order to ensure high reliability and corrosion resistance of such products, make them from high-quality steel with a zinc coating.
An improved model of this type of anchor bolt is a double-expansion anchor, which, due to its design features, can be successfully fastened not only in durable concrete, but also in hollow and porous materials. Such a bolt has two bushings at once, which expand during the process of tightening the threaded element, creating a more reliable fastening in the wall or foundation.
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Types of anchor fastening
Based on the installation method, they are divided into three categories:
- fastening due to mechanical changes in structural elements;
- with the addition of adhesive fixing fillers;
- using vibrocaulking.
Based on the type of fastening, they are divided into the following categories:
- wedge;
- bushing;
- expanding;
- driving;
- special.
The first type is structurally made in the form of a metal rod, at the end of which a cone with a spacer sleeve is formed. On the opposite side there is a thread. To improve consumer characteristics, the fixing nut is installed in tandem with a washer. The rod itself is inserted into a metal sleeve. When the bolt is screwed in, the bushing becomes wedged.
With a sleeve anchor, the sleeve is comparable to the length of the rod. A wedge head is made at its end. At the time of installation, the sleeve expands. Thanks to this, its diameter increases and it fits more tightly to the walls of the hole. This fastener is used in more porous building materials: lightweight and porous concrete, ceramic bricks, building materials with various additives.
One of the varieties of such an anchor is an expansion bolt. It has a more complex design due to the use of a 4-leaf spacer sleeve. For the most reliable fastening, an expansion spring with an expansion nut is inserted into the bushing. Changing the shape of the bushing can significantly increase the engagement force and load-bearing capacity. This fastening system does not create increased internal stresses in the contact zone. This significantly increases the service life of the entire mount. The expansion anchor is expensive. Therefore, it is used only by professional builders in critical construction areas. Where it is necessary to fasten the part to masonry made of cellular concrete or hollow brick.
The drive-in anchor gets its name from the way it is installed. It is secured using impact tools: a hammer, a mallet, a rotary impact drill.
To solve non-standard problems, special anchors are manufactured. These include:
- frame anchors with PVC sleeve;
- self-tightening bolts;
- anchors for hollow structures;
- some types of screw anchors;
- fasteners for geogrids.
Modern manufacturers offer a wide range of anchors for various building materials. The main types are given below.
With nut
An anchor fastener with a nut is one of the most common among such fixing devices. Its popularity is due to its simplicity of design, reliable connection and low price. Structurally, it consists of three parts:
- screw with conical thickening;
- steel tube (equipped with slots for more efficient expansion);
- fixing nut (when screwed onto the bolt, it retracts).
The principle of operation is quite simple. Due to the rotation of the nut, the bolt moves along the rod. This causes the tip of the rod to expand. The further the nut moves, the stronger the connection.
An anchor of this design is used for fastening parts in wall and ceiling structures. Permitted materials for use are dense concrete, solid silicate or ceramic bricks, and various types of natural stone. The main overall dimensions are the outer diameter of the rod, the length of the bolt, and the metric size of the nut. In practice, anchors with a diameter of 6 to 28 millimeters are used. In length, manufacturers produce products from 60 to 300 millimeters.
Wedge
This anchor bolt is a modification of the design discussed above. The main difference is the sleeve placed at the end of the rod, which, when expanded, creates the necessary effect. At the other end there is a nut and lock washer screwed on.
The scope of application coincides with the anchor bolt and nut. It is made from carbon or stainless steel. The galvanizing process is used to protect against corrosion.
The main mechanical characteristics are:
- geometric dimensions (the diameter of the bolt is made from six to twelve millimeters, the length of the entire structure is from forty to one hundred and twenty millimeters);
- permitted thickness of the product that can be attached (no more than twenty millimeters);
- thickness of the bearing surface (not less than 53 mm);
- the value of the pulling force (with proper installation it reaches 6 kN).
Installation is carried out using a standard set of tools. To understand how to fasten an anchor bolt of this type, it is enough to familiarize yourself with the method of fastening conventional anchors. A part secured with a wedge anchor can withstand heavy loads. This is possible due to the creation of high internal stress, which significantly increases the value of the tearing force.
Hex head
To fasten structures with heavy weight to surfaces with increased hardness, use an anchor bolt with a hex head. It is especially widespread during repair and design work, in which the aesthetic design of fastening elements is of great importance. This is possible because during installation the rod (stud) does not move in the opposite direction.
The design difference is the presence of a hexagonal head. When installed, it rotates along the threads of the spacer bolt, which causes the bushing to expand. The material used for manufacturing is yellow-passivated galvanized steel. This provides good anti-corrosion protection.
It is advisable to tighten such a bolt using an appropriate spanner or socket wrench. The hexagonal head design allows the effective use of electric tools, such as a wrench. When installing it in the hole, you must ensure that there are no distortions or displacements.
Drums
A driven or impact anchor bolt is used at the initial stage of construction or the rough finishing stage for fastening massive structures. With its help, heavy parts are fastened up to load-bearing structures, routes are laid for cables and plumbing equipment, and suspended elements of building structures are mounted. The main condition for use is the required density of the base where the anchor is installed.
The main characteristics are:
- the length of the entire bolt structure (manufacturers produce products from 25 to 50 mm);
- outer diameter (the size is determined by the manufacturer, but according to established standards it can reach 20 mm);
- the thickness of the part that is fixed is not standardized;
- the minimum thickness of the base in accordance with established standards must exceed 100 mm;
- The magnitude of the pullout force, depending on the dimensions of the bolt and the density of the base, varies from 3.9 to 12.6 kN.
To ensure the reliability of the connection, you should understand the principle of operation and imagine how to correctly drive anchor bolts?
Fastening the part with a driven anchor bolt is carried out in the following sequence:
- a hole of the required diameter of a greater length than the anchor itself is drilled in the load-bearing surface;
- the hole is cleaned of any dirt and dust that has formed;
- using a hammer, hammer the sleeve into the hole (under the influence of the impact load, the split part of the anchor expands and fits tightly to the walls of the hole);
- screw in a bolt or pin (fastening the required part).
The anchor bolts must be driven in perpendicular to the fastening surface for the entire length of the bolt.
Four-segment
Anchors of this type are used for fastening structures with large weight and size characteristics. The presence of four segments in the sliding part gives the fastening increased reliability. It has an increased degree of wedging and is used not only in solid materials, but also in materials with a porous structure.
The anchor sleeve is made of galvanized steel in the form of four independent segments. On one side the segments are fastened with a ring. On the other hand, the segments are fastened with a restraining spring. A spacer element is provided to increase efficiency.
When a bolt is screwed into an anchor, it moves down the anchor. At this moment wedging occurs. Thanks to this design, reliable fixation is ensured along the entire length of the anchor.
Screw
This type of bolts is made from rebar. It represents a long screw with a large pitch thread. Fixation in the prepared hole is achieved through the hardening of mineral, polyester or other special fillers. Screw anchors are used from mining to capital construction. When they are fixed in a brick wall, it is possible to obtain a reliable connection. The kit includes: screw rod, washer, spherical nut.
The use of special fastening fillers ensures reliable and durable fastening.
Dimensions and characteristics of anchor bolts
Anchor bolts for concrete are classified according to size into three groups:
- small - with a diameter of up to 8 and a length of up to 55 mm;
- medium - up to 12x120 mm;
- large - maximum size 24x220 mm.
Mark the anchor according to the dimensions, indicate the thread diameter, drill number, thickness of the attached part, and the depth of the mounting hole.
For example, the designation of fastener M8 10/60-115 stands for:
- thread diameter - 8 mm;
- drill diameter - 10 mm;
- anchor length - 115 mm;
- The thickness of the attached element is 60 mm.
Technical characteristics - minimum pull-out force, permissible bending and maximum torque, weight of hardware - are indicated in the table of fastener parameters.
Wing bolts and nuts made of plastic
Such fasteners are also made from unnecessary scraps of plastic pipes.
On a note! They are great for various threaded connections, and you can screw them on even without a wrench.
In addition to the pipes, you need to prepare:
- construction hair dryer;
- vice;
- cutting tool;
- large socket head;
- bolts and nuts.
Plastic tubes are crushed in any way, for example, using a miter saw, electric planer, etc. The bolt is placed with a rod in the socket head, a washer and nut are put on. The fastener head is clamped in a vice, plastic shavings are placed inside, and heated with a hair dryer (you can use a gas burner instead).
As soon as the plastic begins to shrink, new portions of chips are gradually added. Afterwards, the semi-liquid plastic mass is pressed with the head of the bolt, which is the size of the socket head. When the plastic has hardened, the finished wing bolt is removed from the head, and the excess mass is cut off with a sharp knife.
Installation instructions
Concrete anchors are installed before pouring the monolith or on a ready-made foundation. In the first case, a pin, bolt or other embedded part is secured with wire or welded to the reinforcement frame, then the solution is poured.
To protect the thread from contamination, it is covered with film. Subsequent work begins after the concrete has gained strength.
In the second case, the technology includes preparing the well and installing the product.
Drilling
Before installing an expansion, drive or expansion anchor bolt in concrete, prepare the hole:
- Mark the positions of the hardware on the base
- Using a drill or hammer drill, drill a hole 20 mm longer than the rod and with the diameter recommended by the bolt marking.
- Using a vacuum cleaner, clean the hole from drilling residues.
If you need to secure any part to the base, first drill it, and then make a hole in the supporting element through the finished hole.
Installation of anchor with nut
Installing an anchor bolt with a nut is used to secure structures of small thickness, for example, a wooden board or a metal corner, to the base.
The bolt is driven into the hole with a hammer, and the nut is tightened with a wrench. It is recommended to use a block of wood or a piece of board to avoid damaging the top threaded part of the hardware.
If the bolt needs to be removed, loosen the nut and remove it from the wall.
To hang household appliances or equipment on a vertical surface, use anchors with a bracket instead of a nut. It is screwed in all the way, making sure that the hook takes the desired position.
Chemical anchor installation
Liquid or injection dowels are installed according to the manufacturer's instructions. They are produced in capsules or cartridges.
Each type of installation has its own characteristics:
- The capsule is placed in the hole, then a bolt or pin is screwed in. Wait until the composition has completely hardened.
- The cartridge is loaded into the gun, the well is filled under pressure, and the hardware is installed.
Preparatory work
We screw two elongated nuts onto the stud, press them together, and scald them. The weld seam must be cleaned - this can be done on a grinding machine or using a grinder.
If you don’t have any power tools at hand, you can process the part using a file.
From sheet metal 10-12 mm thick, we cut out a diamond-shaped blank (“tongue”).
Next, on the grinder you will need to sharpen the end of the bolt with the hook to a cone.
Hex head
The threaded part of such a fastener is a classic bolt, the reverse end of which also has a conical shape. Screwing into the spacer sleeve, such a bolt opens it with its conical shank, ensuring reliable fastening of the product to the wall or foundation.
Such an anchor should be secured by inserting and carefully hammering it into a previously prepared and cleaned hole. Then you need to securely fasten the bolt by tightening its hex head.
Procedure for installing a hexagonal anchor bolt
Bolts of this type, which may have a hook or ring instead of a hex head, are used to perform installation work on concrete, stone and other building materials with a dense internal structure.
Homemade anchors and wing bolts: made in five minutes from available materials
Some construction and repair work requires the use of reliable fastening elements - anchors.
For example, to hang heavy cabinets on a concrete wall, you definitely cannot do without such fasteners. In order to save money, expensive parts can be replaced with homemade ones made from waste materials or cheaper products.
Finished elements will not be inferior in quality to factory ones and will last no less a long time.
Making your own anchor
Drums
Anchor bolts of this type consist of:
- a hollow metal rod, on the upper part of which there is a thread for a fastening nut, and the lower part is a spacer coupling with longitudinal slots on the side surface;
- a striking element (nail), which, when driven into a hollow rod, precisely ensures the expansion of its lower part;
- nuts and washers, which are needed only to secure the required object with such a bolt.
The hole for the impact anchor is made with a drill slightly larger in diameter than the anchor itself
Thus, in order to correctly and reliably fasten such a bolt in a wall or other building structure, it is necessary not only to insert it into the mounting hole, but also to drive an impact element into it, which will open the petals of the spacer coupling.
Taking into account the fact that when installing such a bolt, significant shock loads arise, it is not recommended to fasten it in porous and fragile materials.
Impact Anchor Bolt Installation
Installing an anchor in a concrete wall
Now the main thing: how to hammer an anchor into a concrete wall. Step-by-step instruction:
- Assess the condition of the wall. When calculating the length of the hole for the anchor, the thickness of the plaster layer is not taken into account, since it weakens the fastening of the hardware.
- It is necessary to select a drill of the required diameter (equal to the outer size) of the fastener shell. A smaller drill size is allowed, but never larger.
- Measure the location of the fastening and apply markings.
- Drill a hole. To do this, use a hammer drill. You can also use a drill, but it will be difficult to make a hole in a concrete wall. The drill for concrete should be: carbide, with carbide brazed plates, with a special coating. Conventional drills are not used in this case.
- Clean the hole from dust. Use a brush, vacuum cleaner or compressed air.
- Insert the anchor into the hole. If it is tight, you can gently tap it with a hammer. Strong blows are not recommended. The fastener may be damaged.
- Unwedge the anchor. The method depends on the type of fastener. In wedge and spacer - this is done using a nut and a wrench. In the hammer - a hammer.
Four-segment
The design of such an anchor bolt does not include a wedge part, and the expansion of the spacer sleeve, divided into four segments by longitudinal slots, occurs when the bolt is screwed in, which moves the tetrahedral element in its internal cavity. The four lobes, which are formed by slots on the side surface of the spacer, are initially compressed and form the conical tip of such a bolt. When a bolt is screwed in, which moves a threaded tetrahedral element inside the spacer sleeve, the segments expand, which allows the anchor to be securely fastened in the mounting hole.
The fairly large expansion of the lamellas of this anchor ensures responsible fastening in various types of materials
The petals of such a product open quite wide and this happens very carefully. That is why it can be mounted in porous and even hollow materials. The threaded element, which is usually not supplied with such an anchor product, can be a bolt with a regular hex head or a bolt whose upper part is crowned with a ring or hook.
Installing a 4-segment anchor
General recommendations
In order to correctly install anchor bolts, it is necessary to take into account the type and strength of the base, select the optimal type of anchor for a particular part and determine its load capacity.
And although some types do not require high precision hole drilling (for example, expanding), the more accurate it is, the more reliable the anchor’s adhesion to the base.
Information to note : Liquid glass , Solvent 646, white spirit.
Anchor bolt. Installation operating principle.
How to make an anchor with your own hands
In some cases, it is much easier (and cheaper!) to make an anchor yourself than to waste time looking for it in stores.
Materials required to make the anchor:
- extended nut - 2 pcs;
- sheet metal;
- hook bolt;
- metal washer;
- screw.
Drivers
A drive-in anchor is the simplest anchor-type fastener, the design of which consists of a spacer sleeve with a conical-shaped internal hole. To install such an anchor bolt at the required point in the building structure, it must be hammered into the mounting hole, and then a threaded element must be screwed into it, which will ensure the loosening of the bushing petals.
The material for the manufacture of such fasteners, the correct installation process of which can be seen in the video, can be galvanized steel or brass.
Attaching a drive-in anchor
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Drive-in anchor - how to attach an anchor bolt
One of the easiest types of anchor to install.
The device is a threaded bushing that has slots at the driven end, a conical internal shape and a wedge.
Installation - a hammer anchor is inserted into the prepared hole and, using a special impact attachment, the cut part is pushed apart with a wedge. When the anchor bolts are screwed in, the petals spread even wider, increasing grip.
Made from galvanized steel or brass.
Screw
The design of the screw fastener, which is very easy to use, differs from all other anchor-type products. The slots on the spacer sleeve of such an anchor, which ensure its expansion during installation, are made in its middle part and have a weakened design. The lower part of such a sleeve is a nut into which the anchor bolt is screwed, compressing it along its length and ensuring the opening of the petals.
Screw anchors are called anchors of different designs.
The process of installing a screw anchor bolt can also be seen in the video. Such an anchor can be fastened in “weak” materials: porous concrete, brick, etc.
Screw anchor
Has a special design. The slots in the sleeve are not cut completely and end with a ring with a nut. Closer to the head and in the middle of the liner, the lamellas are weakened. When tightening the screw, the nut moves and pushes the lamellas apart in the middle.
Specially designed for weak and hollow substrates. It can be produced not only with a screw, but also with pins, hooks, and rings.
Anchor bolt with ring