Hind Hydrafoam PU injection is used for cracks in concrete to stop the flow of moving water. It will provide an effective system for cracks sealing in wet conditions. It is a complete system for water cut off in concrete, masonry structures where strong leaks are encountered. The system only reacts when it comes into contact with water, providing semi-flexible polyurethane foam, thus providing permanent solutions to the leaking problems.
Semi- flexible Polyurethane resin type is designed to stop the movement of water in cracked concrete. Crack widths of between 0.1 mm and 5 mm can be treated depending on the water flow. Hind Hydrafoam PU is designed as a solution to water ingress or movement to structure and must be used in conjunction with manufacturer provided catalyst proportion to make homogeneous grout for stopping the water flow, which become when contact with water from hydrophobic reaction and chemically resistant semi flexible polyurethane foam. On certain injections it is advisable to give second pass using varying the catalyst ratio from 5% to 10% to provide a flexible seal. The reaction time can be adjusted from 10 minutes to 30 seconds.
The following properties were obtained at temperature of 200 C unless otherwise specified.
|Pot life in the absence of water||6-8 hours at 200 C3-4 hours at 300 C|
|Reaction time with water||5-30 secondsDependent on temperature|
|Specific gravity||1.14 0.06|
|Density of foam||0.025|
|Viscosity||3-5 poise at 200 C|
Water-stopping crack injection resin
The foam water-stopping crack injection resin shall be a two part foaming liquid polyurethane. When mixed in the proportions supplied and injected to cracks in concrete, the resin shall react with moving water to from a foam water stopping barrier.
The water-stopping injection resin shall have the following properties ; pot life, in the absence of water, 6 – 8 hours at 200C, 3-4 hours at 300C; reaction time with water, 5-30 seconds, dependent on temperature; viscosity of 3 – 5 poise at 200C specific gravity of 1.14 ± 0.06; foam density of 0.025.
When used in conjunction with flexible polyurethane resin type, a flexible two part Polyurethane injection resin shall form a permanent seal in cracked concrete.
Hind Hydrafoam PU can be applied using either injection packers fixed into holes drilled directly into the crack or drilled diagonally from concrete adjacent to the crack or by the fixing of injection nipples bonded to two surface using Hind Proof No.3 admixed with cement. On wide cracks and where there is a large flow of water the use of Hind Plug S, rapid setting cement based, water stopping mortar, should be considered for initial control of water.
If water flow permits, clean the surface adjacent to the cracks and remove any dust, unsound or contaminated material, plaster, oil, paint, grease, corrosion deposits or algae.
The surface should preferably be prepared using high pressure water jetting or light abrasive blasting, followed by thorough washing to remove dust and remaining particles. Dirt alone may be removed with wire brushes or similar mechanical means.
Oil and grease deposits should be removed by steam cleaning, detergent scrubbing or the use of a proprietary degreaser. The effectiveness of decontamination should then be assessed by a pull-off test. Blow the cracks and treated surface with oil free air to ensure complete removal of all dust and loose particles.
Fixing injection packers
The injection packers inserted into pre-drilled holes shall be fixed at intervals along the length of each crack. The distance between each packer will depend upon the width and depth of the crack. Spacing shall be close enough to ensure that the resin will penetrate along the crack to the next point of injection. This will normally be between 200 mm to 500mm.
Where practical the surface of the cracks between the packers shall be sealed with a band of polymer mortar, 30 to 40 mm wide and 2 to 3 mm thick. Both sides of any cracks which go all the way through a wall or slab shall be sealed this way. Please note where water flow is severe the polymer mortar application can be omitted.
In the case of a wall or slab which is cracked all the way through, packers shall be located on both sides with those at the back placed at midway points between those at the front. Where application, the polymer mortar shall be allowed to cure for 8 hours at 350C. At low ambient temperatures (5 0C To 12 0C) the curing time will be extended and the applicator shall ensure that the surface sealant has adequately cured prior to continuing.
One end of the injection hose shall be attached to the lowest packer on vertical cracks or to either end of horizontal cracks. Each crack shall be treated in a single, continuous operation. Sufficient material shall, therefore, be made ready prior to the commencement of the work.
Remove the packers or nipples. Apply any holes or voids with Hind Plug S, or Hind Grout GP and allow to cure. Do not allow to burn.
Hind Hydrafoam PU and polymer mortar should be removed from tools, equipment and mixers with solvent immediately after use. Hardened material can only be removed mechanically.
6 months from the date of manufacture stored at 200C , in a dry place in unopened containers.
Hind Hydrafoam PU is supplied in 21 Kg. (Pack A – 20: Pack B -1) HDPE Container
Hind Hydrafoam PU contains isocyanate which may cause sensitization by inhalation. During use avoid contact with skin and eyes and inhalation of vapour. Wear suitable protective clothing, gloves and eye/face protection.
Should accidental skin contact occur, remove immediately with a resin removing cream followed by soap and water. Do not use solvent. In case of contact with eyes, rinse immediately with plenty of clean water and seek medical advice. If swallowed seek medical attention immediately do not induce vomiting. Use only in well ventilated areas. In cases of insufficient ventilation wear suitable respiratory protective clothing.