- Concrete Crack Repair Home
- Floor & Slab Crack Repair
- How crack injection works A cost effective permanent fix for basement leaks
- Low-Pressure Crack Injection (Basement Walls and Foundations)
- Do-it-yourself crack repair A kit for contractors and homeowners.
- Basic steps in the injection pocess Installing injection ports, sealing, epoxy vs. polyurethane, injection and port removal
- Allowable crack widths At what width does a crack become a problem?
- Related Information
- Concrete Repair General overview of concrete repair
- Concrete Patch Repairing cracks in concrete flatwork
- Foundation Repair Repairing a concrete foundation
- Find Crack Repair Products
ADVANTAGES OF DUAL-CARTRIDGE DISPENSING
Dual-cartridge dispensing, using disposable or reusable cartridges or containers, is a cost-effective completely portable method of injecting two-component polymers. The equipment also requires minimal maintenance and virtually no cleanup. At the end of the day, you simply discard the spent cartridges or reseal a partially used cartridge for reuse on another job. Each cartridge contains 16 to 22 ounces of material.
Automated proportioning equipment that dispenses bulk quantities of material also is available and may be the best choice on jobs requiring higher injection pressures or large volumes of material. But this equipment is expensive and cumbersome, and typically overkill for smaller residential jobs requiring only a few gallons of epoxy.
A spring-assisted dispensing tool (such as Rhino Carbon Fiber's Dual Epoxy Gun) allows complete control of injection pressures to keep them between 20 to 40 psithe best range for complete crack filling. The user simply changes the spring tension to adjust the force generated. Manual tools using a drive rod rather than a spring are difficult to control and may result in injecting at pressures much higher than desired. Air-powered tools are also available for dual-cartridge dispensing and allow control of injection pressure.
Because the epoxies and polyurethane foams used for crack injection are two-component materials, it is critical to mix them at the correct ratios to avoid problems with unreacted polymers. The dual-cartridge dispenser also acts as a proportioning device by using a static mixer, available in various sizes, to accurately mix the two components.
"The cartridges and static mixer eliminate a lot of problems," says Cole. "You don't have to be a chemist onsite. You just put the static mixer on the dispensing tool to achieve the right ratio and to properly mix the two components."