| Product Name |
Hollow bolts / Hollow anchor / Self drill anchor / Grouting drill anchor bar / Rock anchor |
| Standards |
GB1499.2-2007 GB 50086-2015 TB/T 3209-2008 |
| Grades |
Carbon |
45#, sae1045, aisi1045 |
| |
Alloy |
40Cr, JIS SCr440, ASTM 5140, ISO 41Cr4 |
| Certificate |
We are SGS approved enterprise, we issue MTC and be responsible for the quality. |
| Outside diameter |
25mm, 25.4mm, 28mm, 28.3mm, 30mm, 32mm, 38mm, 40mm, 51mm, 76mm or as per required |
| Thread standard |
ISO 10208 / ISO1720 |
| Tolerance for OD |
+0mm/-0.2mm |
| Length |
1.5m, 2m, 3m, 4m, 5m, 6m, or as per clients request |
| Surface treatment |
Black / oiled /galvanized or as per required. |
| Heat treatment |
Annealed |
| Test |
Yield strength test, Tensile strength Test, Chemical composition |
| Accessories |
normal head, Alloy bit, expanding head, hex-nut, slurry seal, connector, plate |
| Packing |
Wrapped by anti-water plastic clothes, each bundle two hoisting belts |
| Application |
pre-support, radial support, slope stabilization, foundation support , soil nail, retaining wall, etc. |
| Shipping term |
In bulk / FCL / LCL, partial shipment allowed |
| Shipping port |
Qingdao, or Tianjin port |
| Third party inspection |
Acceptable |
| Trade term |
CIF, CFR, FOB, EXW |
| Delivery time |
Within 7 days for stocks supply. |
| Paying term |
30%TT + 70% TT against copy of documents, or 30%TT + 70% LC. |
Product Description
The product is composed by hollow anchor bar, anchor nut, anchor plate, anchor coupler, drill bit, and the hollow anchor bars can be cut and lengthened by coupling on request. Self drilling anchoring system is an advanced system which can ensure the anchoring effect for complex ground conditions. It can be integrated with the functions of drilling, grouting and anchoring. It can be used in railway system, metro project and infrastructure . As an efficient anchoring method, it's also widely used for pre-support, radial support, slope stabilization, foundation support , soil nail, retaining wall, etc.
Application
Railway System
Metro Project
Slope Stabilization
Hydroelectric Station
Infrastructure
Mining
| Hollow Rock Anchor Bars Accessories |
1. Anchor head: the barb on the anchor head can position the anchor rod in the drilled hole, and the rod body is well centered.
2. Anchor bolt body: the most important structure in the assembly, which plays a major role in anchoring and support.
3. Grout stop plug: maintain the grouting pressure during the grouting process, so that the grout can fully fill the gap of surrounding rock.
4. Base plate: bear greater surrounding rock stress.
5. Nut: concentrate the surrounding rock stress on the base plate.
| Hollow Rock Anchor Mechanical Properties |
| Size |
O.D(mm) |
I.D(mm) |
Ultimate Load(KN) |
Yield Load(KN) |
Weight(kg/M) |
| R25N-14 |
25.0 |
14.0 |
200 |
150 |
2.3 |
| R32L-22 |
32.0 |
22.0 |
210 |
160 |
2.8 |
| R32N-21 |
32.0 |
21.0 |
280 |
230 |
2.9 |
| R32N-18.5 |
32.0 |
18.5 |
280 |
230 |
3.4 |
| R32S-17.5 |
32.0 |
17.5 |
360 |
280 |
3.5 |
| R32S-15 |
32.0 |
15 |
360 |
280 |
4.1 |
| R38N-21 |
38.0 |
21.0 |
500 |
400 |
4.8 |
| R38N-19 |
38.0 |
19.0 |
500 |
400 |
5.5 |
| R51L-38 |
51.0 |
38.0 |
550 |
450 |
6.0 |
| R51L-36 |
51.0 |
36.0 |
550 |
450 |
7.6 |
| R51N-36 |
51.0 |
36.0 |
800 |
630 |
7.6 |
| R51N-33 |
51.0 |
33.0 |
800 |
630 |
8.4 |
| Steel grade |
Acc. to EN10083-1 |
| Thread direction |
Left hand |
| Thread standard |
ISO 10208 / ISO1720 |
| Characteristics & features of hollow grouting anchor rod |
1. Combine the functions of anchor rod and grouting pipe into one. It is a grouting pipe during grouting, and becomes an anchor rod without pulling out after grouting.
The hollow design enables the anchor rod to realize the function of the grouting pipe, and avoids the mortar loss caused by the pulling out of the grouting pipe in the traditional construction process.
3. The grouting is full, and the pressure grouting can be realized, which improves the project quality.
4 due to the role of various accessories, the rod body is well centered. The mortar can wrap the whole length of the bolt body, avoiding the risk of corrosion and achieving the purpose of long-term support.
5. It is easy to install. It is not necessary to process threads on site. It is convenient to install base plates and nuts.
6. Safe, reliable, and time saving. Self drilling system eliminates the requirement for a cased borehole.
7. Simple installation & operation.
8. Choice of drill bits for different ground conditions.
9. Grouting works synchronize with drilling or after drilling. Grout can fill fractures effectively.
10. Anchor bars can be cut and lengthened on request, applying to narrow spaces.
11. It provides higher bonding stress than smooth steel pipe depending on continuous wave thread.
It is the only anchoring system in China that has completely solved many problems of traditional anchoring support at present, combined with the supporting special grouting pump and grouting technology.
Product installation process
1) Drilling: drill and clear the hole with ordinary rock drill.
2) Insert anchor rod: insert the hollow grouting anchor rod with installed anchor head into the hole, and the barb on the anchor head will immediately hang the anchor rod.
3) Install the grout plug, backing plate and nut.
4) Connect the grouting machine: connect the end of the anchor rod with the selected grouting machine through the quick grouting joint.
5) Grouting: start the machine for grouting. If pressure grouting is required to improve the surrounding rock structure, just wait until the pointer on the pressure gauge rises to the design pressure.
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