T Thread Self Drilling Hollow Anchor Rod

T Thread Self Drilling Hollow Anchor Rod

T threads are designed and produced in accordance with T international standards and can be quickly connected and installed on site. Hollow rods have left-hand or right-hand threads for standard rotary impact drilling.

The relative rib area FR, as a parameter of the bonding quality, is close to the optimal value FR = 0.21-0.33. In addition to good bonding, the 45° angled rib surface reduces splitting forces. Crack width at maximum load is less than 0.1 mm.

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Product Description

Hollow anchors refer to rods that transmit structural or geotechnical loads to stable rock strata. The anchor rods are composed of rods, drill bit couplings, plates, grouting plugs and nuts. It is widely used in tunnel pre-support, slopes, coasts, mines, water conservancy projects, building foundations, roadbed reinforcement and the treatment of geological diseases such as landslides, cracks and subsidence as an efficient anchoring method. It is irreplaceable in a small construction environment.

T Thread Self Drilling Hollow Anchor Rod
SIZE	OD(MM)	ID(MM)	Cross Sectional Area(MM²)	Ultimate L(KN)	Yield Load(KN)	Weight(KG/M)	Length(M)
T30/16	30	16	343	220	180	2.70	(1)×2,×3,×4,×5,×6,×7,×8,×9,×10
T30/14	30	14	356	260	220	2.80
T30/11	30	11	406	320	260	3.25
T40/20	40	20	713	540	430	5.60	(1)×2,×3,×4,×5,×6
T40/16	40	16	910	660	525	7.15	(1)×2,×3,×4,×5,×6
T52/26	52	26	1250	929	730	9.90	(1)×2,×3,×4,×5,×6
T73/53	73	53	1680	1160	970	13.20	(1)×2,×3,×4
T73/56	73	56	1369	1194	785	10.75
T73/45	73	45	2267	1588	1270	17.80
T73/35	73	35	2700	1875	1430	21.20
T76N	76	51	2000	1600	1200	16.50	(1)×2,×3,×4
T76S	76	45	2400	1900	1500	19	(1)×2,×3,×4
T103/78	103	78	3220	2280	1800	25.3	(1)×2,×3,×4
T103/51	103	51	5680	3460	2730	44.6	(1)×2,×3,×4

Composition

1. Hollow anchor：

The anchor itself is a full-length thread, which can be cut at will according to customer requirements and lengthened with a coupling. Continuous threads like waves can bond well with cement slurry to achieve better anchoring effect.

2. Anchor nut：

Nuts are connecting devices used with pallets.

3. Pallet (hot rolled steel plate)：

The function of the pallet is to exert anchoring force on the surrounding rock, transfer stress, increase end force, and enhance the anchoring effect. The pallet is installed at the end of the hollow anchor rod, between the nut and the rock formation. According to the shape, it can be divided into dome plate and flat plate.

4. Anchor Coupler：

It is a component used to connect two bolts to each other and can be heat treated according to customer requirements.

5. Drill bit：

A drill bit is a device that performs and withstands the drilling process. Choose from a variety of unique drill bit structures for different rock types.

The biggest difference between this drill bit and other anchor drill bits is that it is disposable. Once the drill bit is drilled with the hollow anchor system, it can never be pulled out again. This also saves the replacement process and simplifies the construction steps. Save a lot of time and cost.

6. Centralizer：

The main function of the centralizer is to maintain the correct position of the anchor bolts during installation. When the hollow anchor rotates at high speed in the hole, ensure the smooth operation of the anchor and keep the drill bit axis as close as possible to the center line of the drilling hole. Without a centralizer, the bolts may deviate from their original positions under harsh ground conditions, affecting the anchoring effect and structural stability.

Installation

The installation of traditional rock bolts can be a time-consuming and labor-intensive process. Predrilling holes requires additional equipment and requires multiple steps to secure the bolts in place. This can result in longer project times, especially for large-scale applications.

The installation of self-drilling anchors is more convenient, faster and faster, and has significant efficiency advantages. Pre-drilling is eliminated, saving time and reducing the complexity of the installation process. Self-drilling capability allows for faster, more streamlined installation.

1. Pre-construction preparation:

Check whether the functions of the drilling rig are normal, whether the drill bit and the hollow anchor bar are broken, and whether the hollow anchor bar is free from damage. After making sure there are no problems, rotate the hollow anchor bar to be used with the drill bit;

2. Drilling and grouting:

Connect the hollow anchor bar and grouting pipe to the drilling rig by rotating the grouting adapter and grouting during the drilling process, so that drilling and grouting are completed simultaneously;

3. Hollow anchor bar extension:

If the length of a single self-drilling anchor bar does not reach the design drilling depth, it can be connected with a coupler to meet the design requirements;

4. Installation of plate and nut:

After grouting is completed, install plate and nut in the exposed part of self-drilling hollow anchor bars against the construction surface in order to ensure the anchoring effect.

Advantages

1. Especially suitable for difficult ground conditions.

2. High installation rate since drilling, pouring and grouting can be completed in one operation.

3. Drilling and grouting can be performed at the same time during installation.

4. Suitable for working in limited space, height and inaccessible areas.

5. Hot-dip galvanizing to prevent corrosion.

T Thread Hollow Anchor