SPOTLIGHT: HECO screw anchors - flexible even under heavy loads

German screw specialist HECO has expanded its range of screw anchors. Here the Schramberg-based firm explains the benefits of new large diameters for heavy-duty anchoring and a version for temporary support mounting in young concrete...

HECO screw anchor range has grown with the MULTIMONTI-plus which is now available in diameters of 16 and 20 mm, and a special version named “SSK” for the temporary fastening of push-pull props in concrete and formwork structures.

The new dimensions mean that the range of approval compliant products is now even broader from HECO, which is bolstering its expertise as a provider of efficient and cost-effective solutions for heavy-duty anchoring with the anchors. The new ETA-rated screw anchors are even approved for multiple use and for insertion in young concrete with a compressive strength of min 10 N/mm². Simple anchor calculation and installation is able to save a lot of mounting time when fixing supports for formwork, for example.

With the large screw diameters of 16 and 20 millimetres, HECO is entering the field of classic heavy-duty anchoring, which was previously dominated by sleeve anchors and resin bolts in particular. For example, when applying the MMS-plus 20 in cracked concrete with a compressive strength of C20/25, tensile resistances of up to 44 kN can be achieved, according to ETA-15/0784 – including all the advantages plus simple mounting when using screw anchors. Screw anchors with diameters of 16 and 20mm recently received an approval for seismic actions C1 and C2. HECO provides the MMS-plus screw anchors in the new dimensions with a hexagon head and a combined washer as well as a pre-set anchor with a metric connection thread.

HECO has developed the MULTI-MONTI-plus SSK in the dimensions 16 x 130mm specifically for temporary anchor plate installation of push-pull props in pre-cast concrete component and formwork structures according to the general technical approval Z-21.8-2061. SSK is a German abbreviation which translates as “hexagon head with washer and cone”. The screw anchor with the proven MULTI-MONTIplus thread and combined washer has an additional, extremely adaptable cone under its head so it can be put flexible use when fastening anchor plates with different sizes of clearance holes. HECO provides customers with a load chart for various compression strengths of concrete as an additional evaluation tool. Furthermore, the MULTI-MONTIplus SSK can be calculated with the HCS calculation software for permanent fixations according to ETA-15/0784.

In the case of smaller hole diameters, the screw secures the base plate by pressing it securely onto the substructure via the conus. The bigger the clearance hole, the further the screw is countersunk when installed in the component to be fastened. The combined washer enables fastenings in even larger clearance holes, so hole diameters of 17 to 23mm in the base plate can be covered with a single screw dimension. Any hole tolerance is reliably eliminated, HECO says. Another practical advantage is that HECO uses a screw head with the size for a 24mm spanner, which is commonly used in formwork structures, so users can therefore work with their usual tools.

Use of all the MULTI-MONTI-plus versions is very easy and saves time. A newly developed function tip reduces wear due  to a larger outer diameter and strengthened serration. The core and thread geometry enables effortless driving and high loads. The anchor can be screwed in easily with a tangential impact wrench.

It is also easy for contractors to determine whether the anchor is suitable for reuse. The gauge used for this is  available in the HECO range and also covered by the approval. If the anchor remains inserted in the gauge without the tip protruding, it can be used again.