To be the best supplier of hollow bar is Sinorock’s aim

posted on 31 Aug 2017 16:25 by hollowbar
With the development of economy, the coal as main energy demand is becoming more and more huge, coal as the main production in the coal industry is also facing the deep development of the problem, with the increase of excavation depth, roadway supporting faces many difficulties, in order to improve the support strength, enhance security, we need to analyze the application of self drilling hollow bar support in coal mine internal.
Self drilling hollow bar is a direct acting within the surrounding rock of roadway,it is different from the old ways such as wood beams , in other words, it is from the past passive support on the outside of the rock into the internal active support, so that we can reduce the deformation of roadway, improving the bearing capacity of self drilling hollow bar support.
At present,there are many coal mining in China has reached more than 1000 meters depth above, not only larger mining depth, but also the complicated geological structure, there exists the possibility of mine disaster,which brings very great difficulty in self drilling hollow bar coal mining support.
So, to be the best supplier of hollow bar is Sinorock’s aim and also it is our responsibility.
To be the best manufacturer for anchor bolt products, Sinorock has formed a strong Research & Development team, in the team there are several senior engineers in the fields of material, mechanical engineering, electrical and mechanical engineering and so on.
To be the best manufacturer for hollow anchor bolt products, Sinorock focuses on product quality extraordinarily, the inspections in Sinorock include incoming inspection, production, finished products inspection.
To be the best manufacturer for hollow anchor bolt products, Sinorock improves the service quality ceaselessly, we have established a comprehensive service system. It concludes 7*24 hours online consultation, great products packaging solutions and professional after-sales service.


The hollow bar anchor technique has been used in the United States as a self-grouting soil nails which replaces the traditional drill and grout method. The drilling, installation and grouting of nailing in this method is combined into one single step. This method proves to be advantageous for caving ground conditions and was initially employed for temporary shoring applications.

The accessories for hollow core bar soil nails include washers, nuts, bearing plates, couplers and centralizers.The drill rig used on soil nailing projects using hollow core bars has the capacity to adapt to various sizes of hollow core bars and drill bits. Hydraulic rotary or rotary percussion drill rigs are commonly used. The rigs can be tack mounted or excavator mounted .The versatility of drilling rigs and concurrent drilling, installing and grouting procedure of hollow soil nails have worked well for remote access.

During tunnel construction, hollow and loose massive accumulation body often appears at portal section. The stability of rock is poor and local region is easy to happen collapse, so pipe shed is adopted to support in advance.

Because of poor rock stability, it’s difficult for drilling machine to form hole. While regular pipe shed is often steel tube with eyelet on its surface, jacking and grouting methods are needed when construction, so it’s difficult to install. Self drilling hollow anchor bar can solve this problem effectively.

Self drilling hollow anchor bar with drill bit can drill hole with common drilling machine. When reaching to designed location, self drilling anchor and drill bit are left in rock body, grouting can be proceeded directly. Unlike pipe shed, self drilling hollow anchor has injected holes on the top of drill bit, slurry is from bottom to eyelet, then diffuses all around to reinforce surrounding rock. Without pulling out hollow anchor bar and drill bit, it has strong adaptation on surrounding rock, even drilling and grouting at loose and broken surrounding rock.

Sinorock hollow bar micropiles for securing the foundations

posted on 25 May 2017 11:20 by hollowbar

Self-drilling hollow anchor bolts within the extensive range of the Sinorock range of foundation and stability control products are moving beyond their traditional applications in underground construction and are being used also as micropiles. Vital to the protection of  infrastructure above underground excavations, the expanded use of the SDA bolt provide efficient underpinning of the foundations of buildings and for stabilizing ground around excavations particularly in hard-to-reach sites with limited working space.

Sinorock hollow bar micropiles can be installed in every ground type and can withstand, reliably, both tension and compression loads of up to 2,750kN in tension and up to 1,910kN in compression. The hollow-bar design of the self-drilling hollow bar micropile system offers a single action for drilling and grouting. As an efficient method of stabilizing the subsoil, micropiling is becoming an ever more important method for preventing settlement of foundations for the long term.
Sinorock self drilling hollow anchor bar overcome these limitations and make the installation faster and more efficient with their one-step process. The bar is drilled into the ground and cement grout is injected through the hollow rod in one operation. During drilling, the grout stabilizes the borehole to prevent it collapsing. Once installed to the required length and after full hardening, the grout transfers the load from the bar into the surrounding soil. The simultaneous grouting ensures full and uniform coverage of grout along the full length of micropile. Extension couplings provides lengthening of the micropiles and the bearing capacity of the connection remains the same as of the bars.