Anchors for concrete - fasten unreliable structures
This type of fastening is used in cases where it is necessary not only to fix some material to the concrete, but also to hold it securely in such a position that no impact could affect the force of attachment. So usually connect with a hard and heavy base some lightweight structures that are easy to disrupt, for example, drywall or wood.
There are anchors made of several types of material: metal, nylon and plastic. The way of fastening at them also happens different: chemical and mechanical .Chemical is akin to glue, and mechanical does not need a special representation. What is based on chemistry, withstands much greater loads and is not afraid of moisture.
In turn, chemical anchors for concrete are divided according to the principle of mixing on ampoule and injecting .The first are presented in the form of a glass ampoule, in which there are two compartments containing the necessary components. This structure is inserted directly into the concrete( into the hole specially drilled under the fasteners) and there it is broken by the driven rod. Injecting anchors look like a syringe, in which there is either a one-component formulation, or a two-component one, which when mixed with the piston is mixed along the way to the outlet.
Mechanical anchor is also not one, there are stubborn, but there are those that are driven in and held by frictional force. By the method of fastening they are divided into spacer , driven , spring and universal .
Self-tapping screws for concrete or nagel - fastening of window frames and door frames
This fastener can usually be used in places where other types of fastening can not be used due to the complexity of the installation or the fragility of the structure. Screws for concrete are often used where the window frame, for example, is located almost at the edge of the slope. Then the situation is ambiguous, if you use other fasteners, then you need a place for the dowel, in which case you can split a piece of the wall. And self-tapping screws will be a miniature alternative, and quite reliable.
They are used without dowels, fasten directly through the profile to the wall, sometimes it may be necessary to pre-drill. In this case, for a reliable fixing, clean the hole carefully from the dust. You can put the screw on the glue for confidence. If you still need to drill a hole, do not use a perforator, shock vibrations will destroy the base, which we so tried to avoid. This screw for concrete is fixed "for centuries", so it is extremely difficult to twist it, sometimes it is impossible, so act reasonably.
Concrete dowel - reliable base
Concrete dowel is used as a fastening base for some screws and anchors. The quality of this material depends on the reliability of your mount, so among them there is also a separation by types. Criterion is the hardness of concrete, it can be heavy, light( porous materials).They differ in resistance to compression: in a heavy one this index is high, for a lung it is low, so it can not withstand the pressure for a long time.
The action of the dowel is based on its wedging. Antennae on its body are directed against the back stroke, so after it was inserted into the wall, it is almost impossible to get it( only breaking the integrity of the hole).
The final "dead" fixation occurs when a screw comes into the dowel, then a wedge occurs, which, together with these antennae, will not let the binding go out ever.
The material of the dowel depends on the field of application, or rather, on the weight of the object, which will be kept on the screw. If it is something light, such as furniture, then a plastic dowel will fit, and for heavy structures there is a metal dowel. For lightweight concrete, the dowels are made of steel, they are made in the form of a "Christmas tree", the principle of operation is the same.
