Hollow Anchor Bar Self-Drilling Anchor Tool Grouting Anchor Rod
Complete hollow self-drilling anchor bar system for drilling, grouting and ground reinforcement in unstable soil, fractured rock, tunnels, slopes and micropile works.
| Product Type | Hollow self-drilling anchor bar / grouting anchor rod system |
| Common Bar Series | R25, R32, R38, R51, T76 |
| Thread Type | Continuous R-thread or T-thread hollow steel bar |
| Typical Yield Load | About 150-1500 kN depending on bar size and wall thickness |
| Typical Ultimate Load | About 200-1900 kN depending on bar size and wall thickness |
| Installation Method | Rotary or rotary-percussive self-drilling with grout injection through hollow core |
| Accessories | Sacrificial drill bit, coupler, nut, bearing plate, centralizer |
| Applications | Slope stabilization, tunnel support, soil nailing, rock bolting, micropiles, excavation support |
Complete hollow anchor bar system for drilling, grouting and anchoring in unstable soil, fractured rock, tunnel headings, slopes, excavations and micropile reinforcement.
Product Overview
A hollow anchor bar is a self-drilling reinforcement member that works as the drill string during installation and as the final anchor tendon after grouting. The hollow core allows grout to be pumped through the bar, while the continuous thread improves mechanical bond with the grout body.
This system is used when conventional drilled holes may collapse before a separate tendon can be inserted. It is especially practical in loose fill, weathered rock, broken strata, sand seams, shallow tunnel portals and water-bearing ground.
The product can be supplied as a complete grouting anchor rod assembly: hollow bar, sacrificial drill bit, coupler, nut, bearing plate and centralizer. This reduces mismatch risk between anchor body and accessories.
Product Image Gallery
Real anchor product images from the current SunSea Steel media library, showing hollow bars, threaded profiles, grouting anchor rods and accessory details.
Technical Specifications
| Product Type | Hollow self-drilling anchor bar / grouting anchor rod system |
|---|---|
| Common Bar Series | R25, R32, R38, R51, T76 |
| Thread Type | Continuous R-thread or T-thread hollow steel bar |
| Typical Yield Load | About 150-1500 kN depending on bar size and wall thickness |
| Typical Ultimate Load | About 200-1900 kN depending on bar size and wall thickness |
| Installation Method | Rotary or rotary-percussive self-drilling with grout injection through hollow core |
| Accessories | Sacrificial drill bit, coupler, nut, bearing plate, centralizer |
| Applications | Slope stabilization, tunnel support, soil nailing, rock bolting, micropiles, excavation support |
Applications and Ground Conditions
Slope stabilization
Used for cut slopes, landslide repair and soil nail walls where boreholes are unstable.
Tunnel support
Applied in face bolting, crown support, portal reinforcement and fractured rock support.
Micropile reinforcement
R51 and T76 systems can be used for small-diameter foundation support and underpinning.
Excavation support
Practical for retaining structures, temporary works and urban deep excavation reinforcement.
Performance Advantages
One-step installation
Drilling, flushing, grouting and anchoring are combined into a single workflow.
Better in unstable ground
The bar remains in the borehole, reducing risk from collapse before tendon insertion.
Strong grout bond
Continuous external thread increases contact area and bond with cement grout.
System supply
Matched accessories simplify procurement and improve jobsite compatibility.
Selection Guide
For general procurement, start with the required design load and ground condition, then select bar series, bit type, plate size and corrosion protection.
| Light support | R25 for shallow reinforcement and low-load soil nailing. |
|---|---|
| General support | R32 for standard slope, tunnel and excavation applications. |
| Higher load | R38 or R51 where stronger reinforcement or longer bond length is required. |
| High-capacity support | T76 for micropiles, heavy forepoling and major ground support. |
Quality Control and Installation Checks
Material and load verification
Confirm bar designation, wall thickness, yield load, ultimate load and weight per meter before production. Mill test certificates can be supplied for export orders.
Thread and coupler fit
Thread profile, coupler engagement, nut fit and plate compatibility should be checked as a complete system rather than separate parts.
Grouting control
Record grout mix, pressure, volume, return flow and curing time. Proper grout filling is essential for bond strength and corrosion protection.
Site acceptance
Installed length, drilling depth, bit diameter and accessory quantity should be recorded for each anchor position.
Accessories, Packaging and Export Supply
Matched accessory kits
Bars can be supplied with sacrificial drill bits, couplers, nuts, plates and centralizers according to project bill of materials.
Export packaging
Bundles are prepared for long-distance sea freight, container loading and jobsite handling.
Custom lengths
Standard and project-specific lengths are available. Couplers support staged installation in confined working areas.
Documentation
Packing list, commercial invoice, mill test certificate and inspection records can be prepared according to order terms.
Why Choose SunSea Steel
- Real anchor product images from the current media library, not generic placeholders.
- Specification-driven quotation covering bar, bit, coupler, nut, plate and centralizer.
- Support for R25, R32, R38, R51, T76 and project-specific self-drilling anchor systems.
- Export-oriented packaging and documentation for international buyers.
- Technical communication focused on ground condition, load requirement and installation method.
- Responsive quotation support through email and WhatsApp template variables.
Frequently Asked Questions
What is a hollow self-drilling anchor bar used for?
It is used for slopes, tunnels, soil nailing, rock bolting, excavation support and micropile-type reinforcement.
What load range is typical for a hollow self-drilling anchor bar?
Typical reference loads range from about 150 kN yield for light R25 bars up to about 1500 kN yield for heavy T76 bars.
Can the hollow anchor bar be grouted through the center?
Yes. Cement grout is injected through the hollow core and exits near the sacrificial drill bit, filling the annular space around the bar.
Which accessories should be ordered with the anchor bar?
A complete order usually includes drill bits, couplers, nuts, bearing plates and centralizers matched to the bar thread and ground condition.
Can self-drilling anchors be used in collapsing boreholes?
Yes. The bar drills and remains in place, so installation does not depend on maintaining a stable open borehole before inserting reinforcement.
How do I choose between R32, R38, R51 and T76?
Selection depends on design load, required length, ground condition, borehole diameter, grout volume, equipment capacity and corrosion protection requirement.
Can the surface be galvanized or coated?
Hot-dip galvanizing, epoxy coating or project-specified corrosion protection can be discussed for permanent works.
What information is needed for quotation?
Send anchor size, length, quantity, design load, drill bit type, plate size, coupler quantity, ground condition and destination port.
Request Technical Support and Quotation
Send your anchor size, length, quantity, design load, ground condition, drill bit type, plate size, coating requirement and destination port. We will match the hollow anchor bar, drill bit, coupler, nut, plate and centralizer as a complete self-drilling anchor system.