Glued anchors, also called chemical or resin anchors, are an alternative solution for mechanical anchors which are not always and not everywhere suitable for use. Under certain conditions it is necessary to use fastenings which do not generate stresses, and glued anchors are ideal for such applications. What are they? How do they work? What types of chemical anchors can we distinguish

What are chemical anchors?

Chemical anchors are a product used in the building industry for building structures, and are a combination of glue and an assembly element. We have here a special tube with resin and a hardener, where both components are spread by means of a squeezer, commonly called a pistol. The proper use of the glues also requires the use of a screen sleeve made of plastic or metal. Glued anchors are described in, specifying their advantages and working principles. It is worth remembering that their choice should be determined by the type of substrate and the goal of assembly.

What types of glued anchors can we distinguish?

There two types of glued anchors. The first one includes catalytic and non-catalytic resins. How do they differ? First of all, in the catalyser to resin ratio. In the case of catalytic anchors this ratio is approximately 10:1, and it is the catalyser which is responsible for proper hardening. However, appropriate proportions need not be maintained – any catalyser volume is ok. In turn, non-catalytic anchors require accurate proportions in catalyser-resin mixtures, which are usually 1:1 or 1:3. Other proportions will not ensure resin hardening. Another type concerns catalytic anchors which include:

  • Chemical polyester anchors – they have high density, quick drying time, and are most often used in hollow concrete blocks; their disadvantage is low resistance to loads.
  • Chemical vinyl-ester anchors – characterised by lower density, but their drying time is short with a simultaneous higher load bearing capacity. Therefore, they can be used for hard materials, such as concrete.
  • Chemical epoxy-acrylic anchors – intended for the biggest loads and use in solid materials – their disadvantage being a long binding time.

We can also select among different packaging types for chemical anchors, and can distinguish:

  • chemical anchors in cartridges,
  • chemical anchors in foil packages,
  • chemical anchors in ampoules.

What are the advantages of glued anchors?

There are numerous advantages of glued anchors. First of all, they do not cause any stresses, and, what is more, the anchors can be used even in damaged and weak substrates, while ensuring high stability levels. They can be used in applications where mechanical anchors are not suitable, e.g. at edge zones or when short spacing is required between anchorage points. In addition, the fastening systems are tighter, as resin precisely fills the fastening hole, preventing any permeability of humidity. The high load bearing capacity of these anchors should also be kept in mind, allowing for the fastening of elements with variable load levels.

Where are chemical anchors used?

The applications of glued anchors can be found in various sectors, such as the building industry, road construction, mining, as well as in structural fastenings. Thus, they can be used in the assembly of protective railings, balustrades, steel and wooden structures, lighting installations, as well as in the assembly of shelves, railings, supporting brackets or platforms. In addition, in order to make the chemical anchorage efficient, it should be made in positive temperatures and after prior thorough cleaning of a drilled hole.