Self-Drilling Rock Bolt Assembly with Integrated Fluid Delivery

The patent combines the drilling function and rock bolt insertion function into a single self-drilling rock bolt that performs both operations simultaneously. The hollow shaft of the rock bolt serves as both the drilling tool and the anchor, eliminating the need for separate drilling and insertion operations. This merging of functions directly addresses the contradiction by maintaining reliable anchoring while dramatically reducing installation time and manual handling steps.

The self-drilling rock bolt is designed with multi-functionality, serving as both a drilling device and an anchoring device. The hollow shaft structure allows it to function as a drill bit while simultaneously serving as the anchor itself. This universal design enables a single component to perform multiple operations that traditionally required separate tools and procedures, thereby improving productivity without compromising reliability.

The hollow shaft design concentrates the material where it is most needed - at the cutting end and along the anchored portion in the strata - while reducing material in the middle section. This local quality optimization maintains the necessary strength and drilling capability while minimizing overall weight. The hollow structure provides sufficient structural integrity for drilling and anchoring functions without requiring solid material throughout the entire length.

The patent employs composite construction with the hollow shaft made from high-strength materials that provide the necessary mechanical properties for drilling and anchoring. By using advanced materials with superior strength-to-weight ratios, the design achieves the required performance characteristics while reducing overall weight compared to traditional solid shaft constructions.

The self-drilling rock bolt performs the anchoring action during the drilling process itself, before the bolt is fully installed in the strata. The hollow shaft design allows grout or resin to be injected through the hollow center during drilling, pre-anchoring the bolt as it penetrates the strata. This preliminary anchoring action eliminates the need for post-grouting operations and ensures reliable anchoring even in soft strata conditions.

The system is designed to perform anchoring through self-grouting or self-resin injection during the drilling operation. The hollow shaft serves as both the drilling tool and the injection conduit, allowing the bolt to anchor itself without requiring separate grouting equipment or procedures. This self-service capability simplifies the overall system while ensuring reliable anchoring in various strata conditions.

The resin or grout is pre-loaded into the hollow shaft of the self-drilling rock bolt before installation. As the bolt is drilled into the strata, the material is automatically injected through the hollow center and dispensed along the bolt length. This preliminary preparation of the anchoring material eliminates the need for separate resin capsule insertion and rupture operations, achieving reliable chemical anchoring while greatly simplifying the operational process.

The self-drilling rock bolt system performs the chemical anchoring operation automatically during the drilling process. The hollow shaft design enables the bolt to self-inject the resin or grout material as it penetrates the strata, eliminating the need for manual coordination of separate anchoring steps. This self-service capability maintains effective chemical anchoring while dramatically improving operational simplicity and reducing the skill level required.