Overview of R25 Self-Drilling Hollow Grout Injection Anchor Rod
Anchor rods are generally suitable for strengthening support in mining tunnels, bridge tunnels, track slope protection, and other areas. Generally, anchor rod holes are drilled using an anchor rod drill, and appropriate anchoring agents (resin powder rolls) are placed. Then, tools such as an anchor rod drill are used to drill the anchor rod into the anchor rod hole, stir and anchor the anchoring agent, and then use tools such as an anchor rod drill to install nuts on it; Right-handed anchor rod, also known as equal strength threaded steel resin anchor rod, is made of right (or left) precision rolled threaded steel, with continuous threads and a full length that can be threaded with nuts. Used in conjunction with anchor plate nuts for tunnel support. The bolt is a replacement product of anti Fried Dough Twists bolt, with superior performance.
Specification of R25 Self-Drilling Hollow Grout Injection Anchor Rod
| R25N | R32L | R32N | R32/18.5 | R32S | R32SS | R38N | R38/19 | R51L | R51N | T76N | T76S | |
| Outside diameter (mm) | 25 | 32 | 32 | 32 | 32 | 32 | 38 | 38 | 51 | 51 | 76 | 76 |
| Internal diameter(mm) | 14 | 22 | 21 | 18.5 | 17 | 15.5 | 21 | 19 | 36 | 33 | 52 | 45 |
| External diameter, effective(mm) | 22.5 | 29.1 | 29.1 | 29.1 | 29.1 | 29.1 | 35.7 | 35.7 | 47.8 | 47.8 | 71 | 71 |
| Ultimate load capacity (kN) | 200 | 260 | 280 | 280 | 360 | 405 | 500 | 500 | 550 | 800 | 1600 | 1900 |
| Yield load capacity (kN) | 150 | 200 | 230 | 230 | 280 | 350 | 400 | 400 | 450 | 630 | 1200 | 1500 |
| Tensile strength, Rm(N/mm2) | 800 | 800 | 800 | 800 | 800 | 800 | 800 | 800 | 800 | 800 | 800 | 800 |
| Yield strength, Rp0, 2(N/mm2) | 650 | 650 | 650 | 650 | 650 | 650 | 650 | 650 | 650 | 650 | 650 | 650 |
| Weight (kg/m) | 2.3 | 2.8 | 2.9 | 3.4 | 3.4 | 3.6 | 4.8 | 5.5 | 6.0 | 7.6 | 16.5 | 19.0 |
Features of self drilling hollow grouting anchor rod
1. Safe, reliable, and time saving.
2. Simple installation & operation.
3. Choice of drill bits for different ground conditions.
4. Grouting works synchronize with drilling or after drilling. Grout can fill fractures effectively.
5. Anchor bars can be cut and lengthened on request, applying to narrow spaces.
6. It provides higher bonding stress than smooth steel pipe depending on continuous wave thread.
Advantages of self drilling hollow grouting anchor rod
1. The self drilling hollow grouting anchor rod adopts good thick walled seamless steel pipe material, fast surface thread forming process, and exquisite accessories, achieving the unity of drilling, grouting, anchoring and other functions of the self drilling anchor rod.
2. There is a drill bit with strong penetration force in front of the self-propelled hollow grouting anchor rod, which can easily penetrate various types of rocks under the action of general rock drilling machinery.
3. It has a continuous standard waveform thread and can be used as a drill rod to complete drilling into anchor holes with a drill bit.
4. The anchor rod body of the drill pipe does not need to be pulled out, and the empty space can serve as a grouting channel for grouting from the inside out.
5. The grouting stopper can maintain a strong grouting pressure, fully fill the gaps, fix the broken rock mass, and high-strength pads and nuts can evenly transfer the stress of the deep surrounding rock to the surrounding rock, achieving the goal of mutual support between the surrounding rock and the anchor rod.
6. Due to the three in one function of this type of anchor rod, it can form anchor holes and ensure the anchoring and grouting effects without the need for special techniques such as casing wall protection and pre grouting during construction under various surrounding rock conditions.
