KEIM Concretal MKH is a mineral corrosion protection and bridging coat for Keim concrete repair systems.
KEIM Concretal MKH is suitable for application as corrosion protection corrosion protection on de-rusted steel reinforcement which, after blasting, exhibits degree of cleanliness SA21/2 to DIN EN 12944-4. For application as bonding bridge, use as follows. For a non-interlocking bond between cement bound substrates and Keim Concretal Repair Mortar for concrete repair to ZTV-ING for applications PCCI and II, and in building construction to DAfStb guidelines.
Single component, polymer modified, cement bound, to be mixed with water. Active corrosion protection for steel reinforcement and protection against chlorides in
the context of concrete repair. Bonding bridge for manually applied coarse mortar with elevated bond strength.
For corrosion protection apply by paintbrush, for bonding bridge apply by brush. Substrate preparation - For Steel reinforcement, The steel reinforcement must be prepared to standard degree of cleanliness SA 21/2 to DIN EN ISO 12944-4. It must have no rust film and be free of other substances that have a release or corrosion promoting action. Quartz free bead blasting is a suitable cleaning method. For Concrete substrates - The substrate must be clean, sound, open pored and absorbent. Concrete substrates must be at least of quality B25. Roughen smooth, dense substrates. Remove dirt, laitance and unsound layers by blasting. Surfaces which have been treated with water repellent sealants or evaporation protection agents are not suitable. Surfaces should be pretreated using a suitable process, such as sand blasting or high pressure water blasting.
Keim Concretal MKH should be added into the required amount of water with constant stirring and mixed to a homogeneous, lump free mixture until a readily brush-able consistency is obtained. The duration of mixing is 5min. Slow running stirrers should be used.
Approx. 3.6 to 3.8lt of water is required for a 20kg sack and approx. 0.9 to 0.95 Litres for a 5kg sack. Water should be added according to temperature conditions: low temperature will require less water than high temperatures.
Application as corrosion protection
Keim Concretal MKH should be applied onto the prepared steel reinforcement using suitable paintbrushes in two or three applications. Two coats are necessary for PCC applications, three coats for SPCC applications. Each coat must be applied all round, covering the entire surface. Care must be taken to ensure that tie wires,
edges etc. are carefully coated in order to achieve the necessary application rate. Waiting time at 20°C: 1st Coat: immediately after de-rusting. 2nd Coat: after a minimum period of 3 hours. Application of bonding bridge: after a minimum period of 3 hours. (3rd Coat for SPCC after a minimum period of 3 hours, application of SPCC after a minimum period of 12 hours).
Application as a bonding bridge
The cleaned substrate must be pre-wetted and kept moist, if possible for 24 hours, but for at least 2 hours before applying Keim Concretal MKH. Apply Keim Concretal MKH onto the prepared area and work in well. Apply bonding bridge over entire area. Apply mixed Keim Concretal MKH within the working time see data sheet. Stiffened Mixed materials must not be diluted with water or mixed with fresh Keim Concretal MKH. Do not allow Keim Concretal MKH to dry out. Immediately apply Keim Concretal Repair Mortar wet-on-wet, otherwise prepare again with fresh Keim Concretal MKH. Work Keim Concretal MKH into large areas, section by
section, to ensure that the subsequent coat of Keim Concretal Repair Mortar can be applied fresh-on-fresh.
- Quantity of mixing water: 3.6 - 3.8 Litres for 20kg of dry powder, or 0.9 - 0.95 Litres for 5 Kg of dry powder
- Mix for 5 minutes
- Working Times: at 5°C 75 minutes, at 20°C 60 minutes, and at 30°C 45 minutes
- Waiting Times: between 1st and 2nd coat at least 3 hours, between 2nd coat and bonding bridge at least 3 hours, (between 2nd and 3rd coat, for SPCC, at least 3 hours, before application of SPCC at least 12 hours)
- Theoretical Consumption: 120g per linear metre 1mm diameter as corrosion protection (2 coats), 180g per linear metre 16mm diameter as corrosion protection (3 coats), 1000-1100g per m2 as bonding bridge (consumption figures dependent on substrate texture and temperature)
- Clean tools, machinery and mixers with water immediately after use. After hardening, mechanical removal is the only option.
- Available in 5 and 20 Kg