'Screw anchors are great for mounting building components on concrete'

Anchors are usually used for mounting building components on concrete. There are roughly three types of anchors: chemical anchors, mechanical anchors and screw anchors. It is not that one of these types is necessarily better than the other, but there are applications where a particular type of anchor offers distinct advantages. Chemical anchors are suitable for fixings in soft materials; mechanical anchors and screw anchors are mainly used in concrete. They are cheaper and easier to work with. Screw anchors are becoming increasingly common because innovations and new approvals make them suitable for a wide range of applications. 

Chemical anchors have undergone considerable development, but the basic principle has not changed. A chemical anchor uses a two-component material, which reacts with the substrate in the borehole and thus fixes the anchor or threaded rod. When assembled, chemical anchors do not exert pressure on the material in which they are secured and are therefore especially suitable for use in masonry and brittle materials. They are relatively expensive; processing may require special tools and curing the material can be time-consuming. 

Mechanical anchors, such as wedge bolts or spread anchors, have a tapered screw at the end that, when tightened, presses metal parts against the wall of the borehole, clamping the anchor in place. A mechanical anchor causes considerable pressure on the material in which it is installed. Thus, there must be sufficient mass around the anchor to prevent the material from cracking. Mechanical anchors are therefore less suitable for weaker materials such as brick, natural stone or gas concrete blocks. The major advantage of mechanical anchors is their low price and relatively easy processing. 

Screw anchors

Screw anchors have a thread, which cuts into the concrete. Thus, the connection is realized only with the thread. When installed, screw anchors exert much less force on the substrate than mechanical anchors and are even easier to work with. The drill hole can be easily cleaned by moving the drill bit in and out of the drill hole a few times after which the screw can be immediately screwed in and loaded. 

Screw anchors can handle very high loads and are suitable for hard stone types and cracked or uncracked concrete. Thanks to innovations, they are now also approved for fixings in various types of limestone, aerated concrete, brick and in hollow-core slabs - even with potential exposure to fire or seismic loads. 

Because screw anchors can also be unscrewed, they are useful for (temporary) constructions such as braces, formwork, scaffolding, tunnel and wall plates. They are also widely used for mounting cable trays, light fixtures, piping systems, suspended ceilings, railings, guard rails and sun blinds.  

The German company HECO Schrauben has developed a comprehensive range of screw anchors. Thanks to an extensive range of official approvals, screw anchors are available for many applications. In addition to the "normal" screw anchors, an MMS-plus V pre-piercing anchor is available for mounting fences and railings. MMS-plus SSK has been developed for temporary fixings of construction props, shoring and scaffolding on construction sites. For the installation of wooden elements on concrete, one can choose between the MMS-plus S or the MMS-TC. The different head types such as round head, flat round head or internal and external threaded anchor allow the assembly of mounting rails, pipes or ceiling systems. 

HECO's MMS-plus is approved for exposure to fire (fire resistance class R120 and fire test in accordance with RWS 180). The anchors are also approved for use in earthquake zones (category C1 and C2) and have ETA approval for multiple use. In addition, they meet the requirements of the VdS Directive CEA 4001 for the installation of sprinkler systems.