Self Drilling Anchor Bolt

Self drilling anchors are special type of rod anchors. Self-drilling anchor consists of a sacrificial drill bit, hollow steel bar of the appropriate outer and inner diameter and coupling nuts.The anchor body is made of a hollow steel tube with an outer round thread. Steel tube has the sacrificial drill bit at one end and the corresponding nut with a steel end plate.Self drilling anchor bolts are used in a way that hollow steel bar (rod) has a corresponding sacrificial drill bit on its top instead of a classic drill bit.


The hollow anchor rods from JiuFu is a fully threaded self-drilling anchorage system which can be simultaneously drilled and grouted into loose or collapsing soils and brittle rock without the need for a casing. 



Self Drilling Anchor Bolts include:


  • A hex nut

  • A load-bearing board

  • Extension coupling, if the anchor consists of multiple Anchor rod parts

  • Hollow anchor

  • Sacrifice bit

  • Galvanized anchor

  • Coupling box

  • Centralizer


Self-drilling anchor bolts applications:

The self drilling hollow anchor bolt combine drilling, grouting and anchoring, and is a self drilling anchor system based on a full-thick threaded hollow rod. It ensures the anchoring effect under complex ground conditions.


1. Self drilling rock bolts are suitable for broken rock, loose soil and difficult drilling conditions, such as fractured zones, rotting rocks, gravel, sand and gravel, backfill foundations.


2. Self-drilling rock anchor bolts do not require pre-drilling, so they can be used even in soft rock conditions.


3. Install with grout. Hollow steel grouting anchor bolts can also be used as grouting pipes for easy installation.


4. For permanent support of tunnels, roof and wall bolting.


5. In slope stabilization, bolts and soil nails can be used to hold and reinforce soil and rock.


6. Used as mini-pillar reinforcement. Micropiles can transfer structural loads to the foundation, thereby limiting the deformation of the building.


7. The drill bit can be used according to the rock conditions.


Features of self drilling anchor bolts:

1. Operation without casing. Anchor rods are also a convenient and time-saving drill pipe.


2. Drilling and grouting can be performed at the same time. Good grouting diffusion radius and reliable anchoring quality can effectively fill cracks.


3. Standard full thread bolts can be cut according to your requirements. Cut bolts can be connected by couplers. Suitable for narrow work spaces.


4. Each of our anchor rods are made of high-quality steel and the most advanced technology to ensure that our quality meets international standards or even better.


5. Self-drilling action produces accurate hole size every time, eliminating the need for carbide drills.


6. Quick and easy installation with reliable and convenient overhead application.


Supporting materials for coal mining, construction engineering and large-scale concrete projects include:


Installation of self drilling anchor bolts:

The hollow steel bar is driven to the required depth by means of rotary percussive drilling. Injection is carried out through hollow steel bar. Injection mixture flows through the holes at the sacrificial drill bit and automatically stabilizes the drilled hole. Injection ends when the mixture begins to exit from drilled hole. The cement grout is most often used for injection of concrete self tapping bolts. The usual water-cement ratio ranges from 0,40 to 0,50.We carry acomprehensive range of various self drilling rock bolts; generally speaking, we have two categories as below:


R25N, R32L,R32N, R32S, R38N,R51N, T76N, T76S, T111N, T111S;


T30/16,T30/14,T40/16,T40/20,T52/26,T73/53,T73/45,T73/35,T103/78,T103/51; All self drilling rock bolts can be manufactured in different lengths, like 2 meters, 3 meters, 4meters, 6 meters or 9 meters. Both left hand thread and right hand thread areavailable upon customer's request. Besides, we also supply a complete range of accessories, including coupling sleeves, steelplates, nuts, centralizers, and various anchor bits.


As a leading self drilling anchor bolts manufacturer, JiuFu Self Drilling Anchor Bolts System provide superior and cost effective bolting solution for unstable ground conditions such as sand, gravel, silt, and clays and in fractured rock formations. Welcome to contact us for detailed information!


You may also want to know:

The Types of Rock Bolts and Reinforcements Used with Rock Bolts

How to Install Concrete Fasteners

How do self-drilling anchors stabilize broken slopes and rocks