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August 12, 2017 18:07

How to fix the anchor bolts

Anchor bolts are one of the main fastening elements without which it is difficult to imagine the process of building and repair.Without these essential assistants impossible installation of almost all structures at the base of which is concrete or masonry.With the German word "anchor" is translated as "anchor", and it is not in vain.The very principle of the anchor bolts is built on the fact that he seems to be holding in concrete curtain design due to its construction.


  • anchor bolts.Applications
  • Classification metal anchors
  • How to install the anchor bolt
  • anchor bolt "butterflies" to a false ceiling cornice
  • installation of anchor bolts to the foundation

anchor bolts.Applications


history anchor bolt started quite recently.Earlier this as a fastener used wooden plugs.The piece of wood cut from a larger diameter tube than the screw size.Then drill a hole in the concrete, slightly smaller diameter and scored in his cap, which, in turn, is screwed into the screw.Under the influence of its expanded tube and does not fall out of the hole, holding the entire structure.

True, this "anchor" had plenty of flaws.Firstly, the wood has not completely suitable characteristics for this purpose.Such plugs are often destroyed by moisture in the concrete.Moreover, they could not be used for installation of heavy structures such as a suspended ceiling.Secondly, the tube had produced manually, which took a long time.Imagine planed more than a hundred pieces of the fastener to make repairs in one room.

To solve these problems, engineers have developed a plastic anchors.They were able to remove part of the difficulties faced by the builders earlier.Such elements have become more accurate in size, they are easier to install, and they are less susceptible to harmful external influences.However, they were not a panacea.The fact that plastic can not withstand heavy loads, under which he usually deformed, leading to structural failure.

Almost all problems have decided to use metal anchor bolts.Thanks to them, it became possible to install on the wall pretty hard structures such as brackets air conditioners, satellite antenna, mount a massive steel door, cable suspenders, which used the anchor bolt with a hook.For the same purpose could well go the anchor bolt with a ring.Due to the different configurations of metal anchors, they are versatile and suitable for different tasks.

In industry anchor bolts used for a long time.If you look at the power line, you can see that it supports stand on a concrete foundation, it is bolted such bots.They put on the drawing data and poured concrete.Then anchors to secure the metal structure.Almost all heavy equipment to large industrial objects mounted on anchors.Calculation of anchor bolts for such structures is one of the most important tasks at the stage of the design object.

Classification metal anchors

types of anchor - bolts

Speaking on the classification of these fasteners, several categories can be distinguished.

Anchor bolts are distinguished by the method of action into two groups:

  1. Chemical anchors.The mode of action of this type of fixture is based on a substance that is encapsulated within the dowels.When a worker sets anchor and begins to tighten, with the adhesive capsule is broken, and fills the hole.Such anchors are indispensable when in the walls or floor slabs, on which they are installed, there is emptiness.However, these fasteners have their drawbacks.With their installation before you attach it to the structure, it is necessary to wait a little time.
  2. mechanical anchors.They are more common and popular than chemical.The principle of operation is based on such an anchor metal sleeve wedging, by the spacer which moves along the inner surface of the sleeve is threaded stud or bolt.


Depending on the design of the anchor bolts, they are divided into several main groups, which differ according to the principle of action.

  1. Wedge.This type of anchor works thanks to a wedge on the end of his sleeve.When it is driven into the hole, the wedge moves along the inner surface of the liner and thereby bursting it, thereby strengthening the anchor bolt in the hole.In some models of fasteners wedging liner is due to be installed inside a special rod, which subsequently is removed, and in its place is placed a special pin.
  2. score.Fastening of the anchors is due to the specially manufactured sleeve edges.These fasteners typically part made of soft metal, and when driving the anchor simply wedged, fixing it in the hole.Such a simple anchor design requires strict adherence to the holes sizes both in length and diameter.Use this type of fasteners mainly in the monolith, concrete or stone.
  3. expander anchors or butterfly.Use of such fasteners mainly in thin-walled materials.This through-anchor sleeve with a special structure that has slits in the middle.When the anchor bolt is twisted, its rear portion moves along the thread, thereby deforming the sleeve.It discloses forming the so-called pitch, which is pressed against the anchor plate to the inner surface.These fasteners are used for fixing to plasterboard structures, plastic or fiberboard.The light weight of this type of anchor bolts, ideal for solving very complex problems.
  4. expansion anchors.This type of fastener the most demanded and popular.Such popularity is based on the fact that they do not need to set the exact size of the hole depth.It works in the collet sleeve expansion method by the movement of the tapered sleeve on it.Such anchors are used in Solid brick or concrete.

material for the manufacture of anchor bolts are high-alloy stainless steel, which is further coated with corrosion-resistant coating.The inner bolt or stud are made with metric thread diameters from 6 mm to 30 mm.Qualitative indicators for the anchors are standard on the breakout force and shear.

How to install the anchor bolt

Hit Anchor installs

This operation does not require any special knowledge or skills, and the right to establish such fasteners can each.On the internet is possible to find a lot of videos, how to fix the anchor bolt.Algorithm installing anchor bolt nut following:

  1. assess the state of the wall.Quite often in the homes of old buildings at the wall layer of plaster was applied, which is not able to hold the anchor.Therefore, the estimated length of the fastening element is necessary to increase the value of the thickness of the plaster.That is, if the mounting bracket is required anchor length of 50 mm, and a layer of plaster of 20 mm, the minimum length of the anchor bolts should be equal to 70 mm.
  2. Pick up a drill diameter of 0.5 mm is less than or equal to the size of the anchor bolt.Do not drill the hole too large.Liner fasteners should go into the drilled hole with a little effort.
  3. Draw marks on the surface.This should be done as accurately as possible, otherwise after fixing anchors, it will be impossible to pull.
  4. Drilling holes in concrete carry hammer drill or impact drill bit with special carbide tip.Brick is better to drill without impacts, to prevent damage to its structure.
  5. drilled hole must be cleaned from dust with a brush, vacuum cleaner or a can of compressed air.
  6. further light hammer blows install the sleeve anchors.If it fails to do, do not beat strongly with a hammer, can spoil everything.Walk once again drill, drill a little shaking to razvaltsevat hole.
  7. is screwed into the sleeve then pin the anchor, and then cheat on her nut.When the sleeve nut reaches, hold it by means of a key.

anchor bolt "butterflies" to a false ceiling cornice


If you are in the house ceiling, the better to install a cornice on a special anchor, the so-called "butterfly".To do this, take the ledge and drill holes in it with a diameter equal to the size of the screw anchors.Then, drilled wells make marks on the surface of the ceiling.Thereafter zasverlivaem ceiling hole diameter equal to the dimensions of the liner.

Install the sleeve into the hole and fasten.One of the design features of such anchors are the hooks at the end of the sleeve, due to which she clings to the surface and does not scroll.Then grab the ledge and fasten it on the screws.When scroll the screws, the sleeve is deformed and expanded, while holding the ledge.

installation of anchor bolts to the foundation


If you need to install the metal structure on a concrete foundation, then after the base hardens, drill a hole with a diameter slightly larger than the size of the bolt.Then fill the hole with a special solution and bring it down to the bolt.After drying the solution set metalwork.