Friction Bolts is a kind of anchor bolts which is specially used in strong support. It is also a kind of advanced materials in underground culvert roof and other projects support. Friction bolt has the features of simple operation and easy use. When installing in spraying anchoring support of the underground support, this kind of anchor bolt has strong anchorage force, large pulling force and big expanding force which makes the whole roof into a complete one to support the stress of the surrounding rock. Friction anchor bolt is a new kind of anchor bolt which has the whole length of anchorage and active reinforcement of the surrounding rock. Its anchor bar is a high strength tube of the vertical slit. When installing in a drilling hole with a larger diameter than that of the anchor bar, friction anchor bar will make big pressure on the wall of the drilling hole and friction preventing the surrounding rock slipping in the whole range. The pressure force, friction force and the supporting force of the anchor plate make the surrounding rock in a stressed state in three directions and achieve the support to the surrounding rock. Under the conditions of anchor bar moving because of blasting vibration, the anchoring force will be increased obviously. When the surrounding rock moves clearly, friction anchor bolt will not loss the supporting force.
Sinorock’s Friction Bolt improves rock stability and safety factors by tightening as lateral strata movement occurs. The Friction Bolt is primarily used in metalliferous mining operations, but is also well suited for rib support in coal operations. Sinorock’s Friction Bolt is available in three sizes:33mm，39mm and 47mm
Installation Procedure:
1. Drill hole at proper diameter and depth. Diameter is determined by on-site testing.
2. Insert Friction Bolt into the hole. A driving tool is fitted into the rock drill’s chuck. Place Friction Bolt and plate onto the installation tool.
3. Using percussion and thrust, fully drive the Friction Bolt into the hole until the Dome Plate is tight against the rock surface.
http://www.sinorockco.com
2013年12月17日星期二
2013年11月12日星期二
Applications of friction rock bolt
Friction hollow anchor bar consists of two parts, a tube and matching domed bearing plate. It is mainly used as a good ground support products in coal mines, copper mines, subways and tunnels, etc.
During the using process, immediate ground support is good for friction rock bolt. But soft rock strtas is not so suitable. so, permanent support and roof support is also not recommended.
The Drilling Hole for Friction Rock Bolt should be cleaned and examined to ensure the friction bolt will insert smoothly. Variation in hole daimeters(due to differing strentths of rock strata or excessively gragmented ground) can yield variations in anchorage capacities at various elevations.
Sinorock Friction anchor bolt completed with dome plate has very high strength split tube with welded ring, which guarantees for very good & typical Lab Pull Test.
During the using process, immediate ground support is good for friction rock bolt. But soft rock strtas is not so suitable. so, permanent support and roof support is also not recommended.
The Drilling Hole for Friction Rock Bolt should be cleaned and examined to ensure the friction bolt will insert smoothly. Variation in hole daimeters(due to differing strentths of rock strata or excessively gragmented ground) can yield variations in anchorage capacities at various elevations.
Sinorock Friction anchor bolt completed with dome plate has very high strength split tube with welded ring, which guarantees for very good & typical Lab Pull Test.
2013年10月26日星期六
The features of anchor bolt
When it comes to the erection of metal building systems, one of the most important aspects is the location of the anchor bolts in the foundation. The incorrect placement or embodiment of anchor bolts can lead to costly errors, or even fatal accidents.
Anchor bolt is used in construction where these are set in walls & columns for supporting ledgers, beams, plates. Further, it is also used for prefabricated concrete panel construction for aiding connection to structural frames.
Some other uses include for attaching stair risers or frame assemblages where these provide for strong and durable support. Here are the features of anchor bolt:
1. They are capable of supporting very large loads.
2. Drilling or cutting of reinforcement is not required for installation.
3. Strength is not sensitive to installation procedures and techniques.
4. Supplementary reinforcement may be easily included in the design.
If you are interested please download it from here：http://www.sinorockco.com/download.htm
Anchor bolt is used in construction where these are set in walls & columns for supporting ledgers, beams, plates. Further, it is also used for prefabricated concrete panel construction for aiding connection to structural frames.
Some other uses include for attaching stair risers or frame assemblages where these provide for strong and durable support. Here are the features of anchor bolt:
1. They are capable of supporting very large loads.
2. Drilling or cutting of reinforcement is not required for installation.
3. Strength is not sensitive to installation procedures and techniques.
4. Supplementary reinforcement may be easily included in the design.
If you are interested please download it from here：http://www.sinorockco.com/download.htm
2013年9月29日星期日
There are differences between soil nails and soil anchors.
Soil Nail are usually used to develop stability in steeply sloping excavation cuts. They are designed to allow the creation of a stable soil mass and can remove the need for conventional retaining structures and anchors.
Soil Nails are commonly used to stabilize the faces of cut slopes. The function is to reduce excavation quantities by the creation of steeply inclined stable slopes to the faces of excavations.
The principal application for Soil Nails is in slope stabilisation, in conjunction with a concrete facing to the slope. They are installed on a relatively closely spaced grid pattern with the objective of creating mass stability in the soil.
As well as the traditional Soil Nails offers a hybrid "active" soil nail containing two steel members: one to perform the role of the passive soil nail and a second pre-loadable component with the dual purpose of pulling the facing concrete onto the soil and improving the shear capacity of the soil.
2013年8月12日星期一
How does soil nail work?
Soil Nail is a construction technique that can be used as a remedial measure to treat unstable natural soil slopes or as a construction technique that allows the safe over-steepening of new or existing soil slopes.
The technique involves the insertion of relatively slender reinforcing elements into the slope – often general purpose reinforcing bars (rebar) although proprietary solid or hollow-system bars are also available.
Solid bars are usually installed into pre-drilled holes and then grouted into place using a separate grout line, whereas hollow bars may be drilled and grouted simultaneously by the use of a sacrificial drill bit and by pumping grout down the hollow bar as drilling progresses.
Kinetic methods of firing relatively short bars into soil slopes have also been developed. Bars installed using Self-drilling Rock Bolt techniques are usually fully grouted and installed at a slight downward inclination with bars installed at regularly spaced points across the slope face. A rigid facing (often pneumatically applied concrete, otherwise known as shotcrete) or isolated soil nail head plates may be used at the surface.[1] Alternatively a flexible reinforcing mesh may be held against the soil face beneath the head plates. Rabbit proof wire mesh and environmental erosion control fabrics and may be used in conjunction with flexible mesh facing where environmental conditions dictate.
Soil nail components may also be used to stabilize retaining walls or existing fill slopes (embankments); this is normally undertaken as a remedial measure.
The technique involves the insertion of relatively slender reinforcing elements into the slope – often general purpose reinforcing bars (rebar) although proprietary solid or hollow-system bars are also available.
Solid bars are usually installed into pre-drilled holes and then grouted into place using a separate grout line, whereas hollow bars may be drilled and grouted simultaneously by the use of a sacrificial drill bit and by pumping grout down the hollow bar as drilling progresses.
Kinetic methods of firing relatively short bars into soil slopes have also been developed. Bars installed using Self-drilling Rock Bolt techniques are usually fully grouted and installed at a slight downward inclination with bars installed at regularly spaced points across the slope face. A rigid facing (often pneumatically applied concrete, otherwise known as shotcrete) or isolated soil nail head plates may be used at the surface.[1] Alternatively a flexible reinforcing mesh may be held against the soil face beneath the head plates. Rabbit proof wire mesh and environmental erosion control fabrics and may be used in conjunction with flexible mesh facing where environmental conditions dictate.
Soil nail components may also be used to stabilize retaining walls or existing fill slopes (embankments); this is normally undertaken as a remedial measure.
2013年7月2日星期二
How to install a rock bolt?
Step 1 Drilling
When install a rock bolt, the first thing is taking care to insure an accurate diameter and a straight hole. The hole must be over drilled to allow any debris to fall to the bottom of the hole when the anchor is inserted. Clean the drill hole by blowing air to the full depth to remove debris.
Step 2 Bolt Placement
Place the nut, washer, bevel washers (if required), and plate on the rock bolt and push the bolt into the hole to the correct embedment depth. You should attach a setting tool to the end of the bolt and drive it into the hole with a sledgehammer once the bolt is stuck in the hole.
Step 3 Seeting the rock bolt
The exposed threaded end of the rock bolt decides the setting tool. A proper space between the setting tool and the hex nut is demanded. Initially torque the bolt to the required torque with an impact gun, pneumatic, or hydraulic torque wrench. This action thus expand the mechanical anchor into the rock with migrating the cone into the shell. Final torque can be checked and adjusted with a manual or hydraulic torque wrench.
Step 4 Testing the rock bolt
Place the jack and frame over the bolt and attach the test rod and couplings to the bolt. Attach the test nut and test plate over the test rod on top of the jack. Test the rock bolt by tensioning the jack to the required test load but never to exceed the advertised yield strength of the anchor. Adjust the loading of the jack to the required final tension and lock in the final pre-stress load. This is done by tightening the rock bolt hex nut with a knocker wrench until a slight reduction is noticed on the jack gauge.
Step 5 Grouting the rock bolt
Grouting from the lowest gravitation point on the rock bolt is a good method. You should grouting constantly until a steady stream of pure grout is seen coming out around the bearing plate or grout tube, and/or from the de-air tube. All air and standing water has been removed from the drill hole by displacement and all cracks and voids in the anchor area are filled with cement grout when the grouting is completed.
This article comes from Sinorock, for more information, please visit from http://www.sinorockco.com/.
When install a rock bolt, the first thing is taking care to insure an accurate diameter and a straight hole. The hole must be over drilled to allow any debris to fall to the bottom of the hole when the anchor is inserted. Clean the drill hole by blowing air to the full depth to remove debris.
Step 2 Bolt Placement
Place the nut, washer, bevel washers (if required), and plate on the rock bolt and push the bolt into the hole to the correct embedment depth. You should attach a setting tool to the end of the bolt and drive it into the hole with a sledgehammer once the bolt is stuck in the hole.
Step 3 Seeting the rock bolt
The exposed threaded end of the rock bolt decides the setting tool. A proper space between the setting tool and the hex nut is demanded. Initially torque the bolt to the required torque with an impact gun, pneumatic, or hydraulic torque wrench. This action thus expand the mechanical anchor into the rock with migrating the cone into the shell. Final torque can be checked and adjusted with a manual or hydraulic torque wrench.
Step 4 Testing the rock bolt
Place the jack and frame over the bolt and attach the test rod and couplings to the bolt. Attach the test nut and test plate over the test rod on top of the jack. Test the rock bolt by tensioning the jack to the required test load but never to exceed the advertised yield strength of the anchor. Adjust the loading of the jack to the required final tension and lock in the final pre-stress load. This is done by tightening the rock bolt hex nut with a knocker wrench until a slight reduction is noticed on the jack gauge.
Step 5 Grouting the rock bolt
Grouting from the lowest gravitation point on the rock bolt is a good method. You should grouting constantly until a steady stream of pure grout is seen coming out around the bearing plate or grout tube, and/or from the de-air tube. All air and standing water has been removed from the drill hole by displacement and all cracks and voids in the anchor area are filled with cement grout when the grouting is completed.
This article comes from Sinorock, for more information, please visit from http://www.sinorockco.com/.
2013年6月21日星期五
Rock bolt installation
Rock Bolt installation involves a complex process of drilling into rock, inserting a steel bar, and filling the void with grout. These steel bars are then connected to the structure or fastened to a horizontal whaler, in the case of an earth retention system this whaler bar combination provides lateral support. This process is used as an uplift restraint system, earth retention system, or a variety of other applications.
A rock bolt is used in tunnels or rock cuts. It transfers load from the unstable exterior to the confined (and much stronger) interior of the rock mass. Rock bolts are almost always installed in a pattern, the design of which depends on the rock quality designation and the type of excavation.There are many types of rock bolts, including self drilling rock bolt, expansion shell rock bolt, friction rock bolt and fiberglass rock bolt, etc. Every kind of rock bolt has its own method to finish installation.Here is the installation instruction of Sinorock expansion shell rock bolt:
1. Drilling and cleaning the hole. In order to have a straight and accurate hole, please use cross-cut drill bit.
2. Putting the anchor bar which has installed expansion shell into the bottom of the hole.
3. Giving prestressing force to the Self drilling anchor bolt and making sure the expansion shell fully opened by using specialized tools reach the design requirement.
A rock bolt is used in tunnels or rock cuts. It transfers load from the unstable exterior to the confined (and much stronger) interior of the rock mass. Rock bolts are almost always installed in a pattern, the design of which depends on the rock quality designation and the type of excavation.There are many types of rock bolts, including self drilling rock bolt, expansion shell rock bolt, friction rock bolt and fiberglass rock bolt, etc. Every kind of rock bolt has its own method to finish installation.Here is the installation instruction of Sinorock expansion shell rock bolt:
1. Drilling and cleaning the hole. In order to have a straight and accurate hole, please use cross-cut drill bit.
2. Putting the anchor bar which has installed expansion shell into the bottom of the hole.
3. Giving prestressing force to the Self drilling anchor bolt and making sure the expansion shell fully opened by using specialized tools reach the design requirement.
2013年6月5日星期三
How to remove rock bolts
Concrete anchors are available in a wide variety of styles. The majority of concrete rock bolts remove easily and often come with removal instructions. There is one type of concrete Rock Bolt that is not meant to be removed, but can be removed with the proper tools. Wedge anchors or expansion bolts lock into the concrete and are difficult, if not impossible to remove. Special concrete anchor extractors have been designed that allow you to removed broken or damaged expansion rock bolts.
1. Put on your hearing protection and safety glasses.
2. Select a socket from the socket set that matches the size of the hex nut tightened to the expansion bolt and place the socket onto the 3/8-inch ratchet.
3. Place the socket onto the expansion bolt hex nut and turn the ratchet handle counterclockwise to loosen the hex nut.
4. Remove the hex nut from the threads of the expansion rock bolt supplier.
5. Secure the expansion self drilling anchor bolt into the chuck of the hammer drill. Refer to the operating manual for the hammer drill to determine the proper procedure for securing the expansion bolt extractor.
6. Fill the hand-pressurized water tank with water and pump the handle of the water tank to pressurize the water.
7. Slide the expansion rock bolt extractor over the expansion bolt and press the trigger of the hammer drill to start drilling around the expansion bolt.
8. Spray water onto the expansion rock bolt extractor as you drill around the concrete anchor.
9. Pull the hammer drill toward you to remove the expansion rock bolt extractor from the concrete.
10. Remove the loose expansion rock bolt from the concrete.
11. Wipe the area around the expansion rock bolt with clean rags to clean the surface of the concrete.
1. Put on your hearing protection and safety glasses.
2. Select a socket from the socket set that matches the size of the hex nut tightened to the expansion bolt and place the socket onto the 3/8-inch ratchet.
3. Place the socket onto the expansion bolt hex nut and turn the ratchet handle counterclockwise to loosen the hex nut.
4. Remove the hex nut from the threads of the expansion rock bolt supplier.
5. Secure the expansion self drilling anchor bolt into the chuck of the hammer drill. Refer to the operating manual for the hammer drill to determine the proper procedure for securing the expansion bolt extractor.
6. Fill the hand-pressurized water tank with water and pump the handle of the water tank to pressurize the water.
7. Slide the expansion rock bolt extractor over the expansion bolt and press the trigger of the hammer drill to start drilling around the expansion bolt.
8. Spray water onto the expansion rock bolt extractor as you drill around the concrete anchor.
9. Pull the hammer drill toward you to remove the expansion rock bolt extractor from the concrete.
10. Remove the loose expansion rock bolt from the concrete.
11. Wipe the area around the expansion rock bolt with clean rags to clean the surface of the concrete.
2013年5月29日星期三
New developments in self drilling rock bolt technology
The mining industry is continually striving to develop more effcient methods to support the roof and walls of roadways and tunnels, and rock bolting has proven to be one of the most significant improvements in ground support over the last 50 years. Rock Bolt is now almost universally used in the underground mining industry worldwide, and there are many different rock bolts available.
Rock bolts are traditionally made from steel or fiberglass and are anchored into a borehole with a friction-anchor device, such as an expansion shell mechanism; cement grout; or chemical resin. Friction-anchored bolts are widely used in the Australian metal mining industry, predominantly as short-term support. They are used in conjunction with resin-anchored bolts where there is a requirement for longer life. Resin-anchored bolts are used in the coal mining industry.
Friction-anchored bolts provide immediate rock support, but their load transfer capacity is poor compared to resin or cement anchor bolts. In addition, friction-anchored bolts are more susceptible to corrosion than resin or cement self drilling anchor bolt.
Resin-anchored bolts typically use a plastic resin cartridge that contains mastic and catalyst components that are separated by a thin plastic film within the resin cartridge. The resin cartridge is insertd into the bolt hole before the rock bolt, and the rock bolt is pushed into the bolt hole to push the resin cartridge to the back of the hole. Then, the bolt breaks the plastics cartridge, and the bolt is rotated to thoroughly mix the mastic and catalyst components together. The mixed resin then flows down around the bolt and cures and hardens to anchor the bolt in the hole. These resin-anchored solid bolts work well and provide immediate roof support because the mixed resin typically cures and hardens in less than 60 seconds; it often cures in less than 15 seconds when resin capsules are used. However, bolts and anchored with resin cartridges have a significant disadvantage in that they require considerable manual handlingand several process steps to install, such as hangling drill steels, bolts, and resin cartridges http://www.sinorockco.com/.
Rock bolts are traditionally made from steel or fiberglass and are anchored into a borehole with a friction-anchor device, such as an expansion shell mechanism; cement grout; or chemical resin. Friction-anchored bolts are widely used in the Australian metal mining industry, predominantly as short-term support. They are used in conjunction with resin-anchored bolts where there is a requirement for longer life. Resin-anchored bolts are used in the coal mining industry.
Friction-anchored bolts provide immediate rock support, but their load transfer capacity is poor compared to resin or cement anchor bolts. In addition, friction-anchored bolts are more susceptible to corrosion than resin or cement self drilling anchor bolt.
Resin-anchored bolts typically use a plastic resin cartridge that contains mastic and catalyst components that are separated by a thin plastic film within the resin cartridge. The resin cartridge is insertd into the bolt hole before the rock bolt, and the rock bolt is pushed into the bolt hole to push the resin cartridge to the back of the hole. Then, the bolt breaks the plastics cartridge, and the bolt is rotated to thoroughly mix the mastic and catalyst components together. The mixed resin then flows down around the bolt and cures and hardens to anchor the bolt in the hole. These resin-anchored solid bolts work well and provide immediate roof support because the mixed resin typically cures and hardens in less than 60 seconds; it often cures in less than 15 seconds when resin capsules are used. However, bolts and anchored with resin cartridges have a significant disadvantage in that they require considerable manual handlingand several process steps to install, such as hangling drill steels, bolts, and resin cartridges http://www.sinorockco.com/.
2013年5月20日星期一
Sinorock®-Rock Bolt,Self Drilling Anchor Bolt,Soil Nail China Rock Bolts Suppliers & Manufacturer
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