Anchor rod classification--Metal Anchor,Pipe joint anchor rod

ⅠMetal Anchor

Metal anchors can be divided into three categories: mechanical, pipe joint, and bonded according to their anchoring form.

1. Mechanical anchor

Mechanical anchor rods are the earliest to use, with various structures and a large number of anchor rods. The anchoring mechanism of the mechanical anchor rod is a unified body. When the anchor rod is installed, the anchoring mechanism is mainly displaced axially or radially in the borehole through a wedge system to be tight on the borehole wall. The anchoring mechanism transfers most of the anchoring force to the rock formation through the friction connection. When mechanical anchor rods are installed, most of them produce pre-tightening force. Sometimes, even the anchoring mechanism must directly rely on the pre-tensioning force to fix it.

The advantages of mechanical anchor rods are: rapid installation, immediate bearing capacity, secondary tensioning, and anchor rods of certain structures can be recycled. The disadvantage is that the anchoring section in the borehole is relatively short, which can easily lead to rock formation damage and anchor loosening in high-stress areas. The anchoring force is generally low and can only be applied to rock formations with medium stability or above. Mechanical anchors can be divided into wedge-seam anchors, inverted wedge anchors and account shell anchors.

2.Pipe joint anchor rod

The body of the pipe seam anchor is made of high-strength, high-elastic steel pipe or rolled into thin steel plate. There is a slit along the full length of the pipe. The upper end of the pipe is a cone, and a steel bar is welded to the lower end of the pipe. Ring. The wall thickness of the rod body is 2-4mm, and the diameter is mostly Φ35-Φ45mm (required to be 2-5mm larger than the drilling diameter). The length can be processed as required, generally 1.6-2.0m, and the slit width is generally 10-15mm. When the rod body is forced into the borehole by external force, the slotted pipe is forced to compress, and a radial compression stress is generated between the rod body and the hole wall, so that the rod body is firmly expanded and supported in the borehole. The friction between the rod and the hole wall becomes the anchoring force, and it is distributed along the entire length of the rod.

3. Bonded anchor

The bonded anchor rod has simple structure, convenient use, and large anchoring force. It can increase the anchoring length or perform full-length anchoring, and further greatly improve the anchoring force. It is an ideal roof anchoring form. It mainly includes the following types: 1. Steel bar and wire rope mortar anchor rod; 2. Round steel twist anchor head anchor rod; 3. Rebar anchor rod; 4. Finish-rolled right-handed rebar anchor rod; 5. Internal grouting anchor Rod; 6. Recyclable anchor rod

4.New metal thick tail bolt