Injection Packers

Diameter

Various factors including the volume targeted for pumping, the depth of drilling, intended injection pressures, as well as aesthetic and other criteria, influence the selection of the packer size. Packers, designed for placement into pre-bored holes in materials such as concrete or rock, are selected to match the diameter off the drill holes. 

As a rule, and in addition to the packer material, a larger mechanical packer diameter permits higher injection pressures. 5/8” (16mm), ½” (13mm), 3/8” (10mm) and 1/4” (6mm) are most common diameters for man made structures such as concrete substrates and seem to be the best compromise in strength and size and can be called a standard.

Larger diameters are mostly utilized in rock and other natural structures as found in tunnel and mining applications.

Caution: Packers and ports can exit the drill hole at high velocities under pressure. Correctly installed packers of the right dimensions will minimize this probability. In general, larger diameter packers prevent blow-out better than smaller packers.

The size of the drill hole equals the diameter of the packer. We discuss diameters and drilling angles and techniques in detail in our 1-2-3 at 45 Degree Crack Injection Guideline.

Length

The shaft of the mechanical packer needs to be embedded sufficiently deep within the drilled hole to establish an effective compression seal in the substrate. This depth also prevents spalling of the substrate during the installation and injection processes. For more fragile substrates or deteriorated concrete, we recommend using longer packers ranging from 4″ to 6″ (10-15 cm).

During the injection phase, the drilled hole serves as a conduit for the injected product. In instances where the contractor needs to bridge a substrate gap, a longer shaft length can be beneficial. To accommodate such scenarios, SealBoss offers specially designed packers with extended lengths, enabling the accurate delivery of the material to a specific location within the substrate.

Top Mounted Valve Placement

Two types of top-mounted valves are commonly used: zerk-valves and button-head (also known as button-top) valves. Of the two, button-head valves provide a more reliable connection with the least amount of leakage. Certain top-mounted zerk valves are supplied separately, which allows for the observation of injection grout’s port-to-port grout travel during the injection procedure. As soon as the material starts leaking from the succeeding packer(s), the contractor promptly installs the valve.

Bottom Mounted Valve Placement

Valves installed at the bottom or on the stem enable the removal of the packer’s top section shortly after injection, while maintaining the seal of the drilled holes. This arrangement facilitates the patching of the hole with the remaining part of the packer still embedded in the substrate. As a general guideline, packers should not be removed until the injected product has fully cured to ensure the most effective seal.

Surface Ports

Surface ports, which are often utilized for epoxy injection, provide a surface-mounted alternative to packers. They are ideal for situations requiring lower injection pressures or when drilling into the substrate is unfeasible.

These ports are either glued directly to the surface or positioned within a drilled hole. Many of them feature an open or valve-free design to accommodate quick-release connectors, offering a multiple port injection solution. Generally, surface ports come with caps to hinder epoxy backflow, ensuring a clean and efficient injection process.

For applications requiring a firm fit under higher injection pressures, surface ports with zerk fittings are also available. In addition to these, we offer corner ports, specifically designed for installation in 90-degree construction corners.