Injection of cracks and joints repair

Injection of cracks and joints

also known as injection sealing

is a process of repairing dry and wet cracks (that conduct water). Before starting the injection process, an inspection of the cracks should be conducted and the appropriate injection resin should be selected. It is also important to identify the causes of crack formation to better understand their nature and to choose the optimal solution.

Preparation:

• inspect the cracks (element thickness, crack opening, degree of moisture, etc.)
• Secure the work area

• Notch the crack

• Clean off construction dust

• Plan out the location, angle, number of injection holes, and their diameter (more information on proper drilling can be found in the "ResinBau - Proper Injection Drilling" manual)
• Drill the injection holes:

• Close the crack in the surface by applying CrackOn.5 (quick surface closure solution, sets in 4-7 minutes). If the crack is not visible but there is active seepage, you can use a torch to dry the surface and try to locate the crack.
• For large leaks, use LeakFix tamponade immediately to stop the surface leak.

• The injection hole should be cleaned with water under pressure (ideally using a long tube inserted to the end of the hole, through which water under pressure will flow and flush out the entire hole).

• The packer should be installed in the injection hole so that the entire rubber seal is immersed in the hole's diameter plus about 1cm of the body
• If the hole is excessively widened, compress the packer with your fingers and insert it into the hole as described above.
• For long holes in soft materials, where the holes are excessively widened, packers with wings such as PI-SPHW 10/110 or drilling a short hole (5cm) for a larger diameter packer may be helpful
• Packer installation is best done with a drill set to screw tightening (with a clutch). This is the fastest way to install
• The tightening force must be checked for each new object. It is usually the maximum power of the drill for tightening. Sometimes you may need to add one and a half turns with a flat wrench, and sometimes reduce the power of the drill. The appropriate tightening force ensures optimal working conditions. Excessive tightening force can break the rubber seal, and the hole will not be suitable for injection. Remember the tightening force and do it consistently. You can always tighten the packer more if it loosens, but an over-tightened packer will not hold high pressure.

• Check if the pump works correctly and "prime" the pressure gauge to protect it from resin clogging.

• Injection should be carried out from the lowest point of the crack. Install the nipple grease with pre-coating application on the injection packer. Begin injection. The best results are achieved by starting with low pressure and gradually increasing it if necessary. Watch for water or resin appearing in the neighboring packer. If it does appear, stop injection and install the nipple grease on the "vented packer".
• Repeat the process until the section is complete
• (*) If the pump maintains high pressure but there is no sound of flow, the borehole under the packer may have missed the crack

• After injecting 5-8 packers, we recommend repeating the saturation of the packers with resin. The reason for performing another injection in the same packers is the loss of injection material in the crack. This is caused by capillary absorption of low-viscosity resin through pores and small cracks around the main crack in the structure.

• The removal of the injection packer should take place after full curing of the resin (24-48 hours after injection)

Some practical tips to conclude:

• After using the tools and pump, clean them thoroughly using PI-CLEANER. For pump and pressure gauge maintenance, use PI-SAVER
• If the pressure is very low, the flow rate is too high, and no resin or water is visible in the adjacent packer, it may indicate that we have encountered a void. In this case, the resin moves to further corners and will appear later or flow out of the structure. You can move on to the next packer and return to this point in a few minutes when the resin thickens slightly, but injection is still possible
• To better observe the injection process, pour some resin into two plastic cups:

1. This will allow you to determine how many hand pump strokes correspond to a certain resin volume, or in the case of an electric pump, approximately calculate the time to volume. In the case of a diaphragm pump, sometimes it is necessary to reduce the pressure to "0" (with an open valve) to check if it decreases. If it does not decrease, it means that there is no flow in the crack. If it decreases, the resin penetrates, but slowly.

2. Add some water to one of the cups and leave the other without water. This will allow you to observe the resin working time (temperature and humidity affect the working tinge)

Thank you for your attention. If you have any questions or think there is anything else I should mention, please let me know.

I would like to thank Hammpack and ResinBau for providing marketing materials. All data and suggestions presented in this article were determined during practical applications or in the laboratory and therefore are not binding by default. The information, suggestions, and explanations contained in the article are non-binding. I am not able to control the conditions in which the products are used and the knowledge applied, so the user is obligated to conduct their own tests before starting work. The information contained in the article does not constitute a guarantee of suitability for a specific purpose. The user is responsible for complying with regulations and requirements regarding the use of products and knowledge.

?ukasz Jan Jó?wiak