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Resin Anchored Helix Bolt

The Helix Bolt is a resin anchored bolt with improved resin mixing and support capacity for resin bolting applications.

Mining screw bolts can be used in coal mining, bridge and tunnel engineering, we can provide surface heat treatment, and use hot-dip galvanizing to achieve the effect of rust prevention. The length and size can also be customized according to requirements.

PRODUCT DESCRIPTION

The HelixBolt has a unique head configuration designed for improved shredding of resin capsules, better centralising of the installed bolt and improved end anchoring. The augered paddle configuration improves resin mixing, reduces gloving, and minimises voids in the resin to maximise the anchoring strength of the bolt and enhance corrosion protection through centralisation of the bolt within the resin. The patented design dramatically increases the range of resin annulus into which HelixBolts can be installed offering the ability to optimise the design of resin bolting systems.

The HelixBolt is available in both 18 mm and 20 mm diameter bar depending on requirements. The proximal end of the bolt is threaded with a washer, spherical seat, nut and shear pin. The shear pin facilitates spinning prior to pre-loading. The pin shears at a predefined torque to allow the HelixBolt to be preloaded. Each unit can be provided with a collapsible load indicator to confirm correct tensioning of the unit when installed, and to assist in post auditing of the installation.

Benefits of the bolt

Increased range for resin annulus

Improved mixing of resin

Reduced likelihood of gloving

Reduction in resin voids

Improved centralisation of the bolt

Higher support capacity

ABOUT JIUFU

Hebei Jiufu Industrial and Mining Parts Co., Ltd. is a manufacturer specializing in the supply of supporting materials for coal mining, construction engineering and large-scale concrete projects. It mainly produces self-drilling bolts, friction bolts, glass fiber reinforced plastic solid bolts, Post-TensioningBar, resin bolts and other coal mine engineering support We export 12,000 tons of materials a year, with annual sales of 50 million U.S. dollars.

Hebei Jiufu integrates R&D, design, production and manufacturing located in Handan, Hebei, China, adjacent to Tianjin Port and Qingdao Port, it has convenient logistics. It has 14,000 square meters of standardized industrial plants, 13 product automated production lines, 2 large raw material warehouses, 6 advanced bolt production equipment and accessories processing equipment

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5 Reasons Why Bolts Fail & How To Prevent It

Designing fasteners into your application requires a complete analysis of the joints to make sure nothing was missed. Understanding the types of failures that can occur will help with this analysis. Read on to see how to prevent bolt failure.

5 Mechanism Failures

1.Fatigue failure of the bolt.

2.The bolt being directly overloaded by the applied force.

3.Thread stripping of the internal or external threads.

4.The bolt preload is insufficient to resist the applied forces.

5.Excessive bearing stress under the nut face, bolt head, or within the joint itself.

1. Bolt Fatigue Failures

Fatigue failures typically occur within a couple of threads, where the bolt engages into the internal thread. Failure is reached due to the high-stress gradient within the region.

Fatigue failures can be particularly hazardous because they often occur with no visible warning signs and the failure is usually sudden. Fatigue failures are often unknowingly avoided in gasket joints simply because the required crush for the gasket often dictates a torque or bolt tension that minimizes the risk of a fatigue failure. However, changing to a new gasket type later on which requires less crush may be the initial cause of bolt fatigue failure.

It is not unusual to assume that a bolt has failed due to overload when it has failed from fatigue, which can also be a consequence of self-loosening.

2. Bolt Overload

Bolt overload is a result of the applied force being sufficiently high, causing the bolt to fail due to overload, which is a direct result of the axial force being applied acting upon the bolted joint, which then causes the bolt to fracture in the threaded area.

3. Bolt Thread Stripping

In general terms, thread stripping of both the internal and external threads must be avoided if a reliable design is to be achieved. If the bolt breaks on tightening, it is evident that a replacement is required.When a bolt is being tightened, two threads are mated together, which leads to the tightness of the bolt. When the two threads are mated together, shear stress is applied across the threaded section. If this stress becomes too high, the section will shear, otherwise known as thread stripping. This type of bolt thread stripping is severe, and must never be allowed to occur. Its occurrence is a sure sign that there is something seriously wrong with the bolts. If it is observed, the bolting procedures must be re-examined and re-evaluated immediately. If it is allowed to persist, serious consequences may result because the bolts will not only sustain a preload but external loadings may be transmitted directly to the bolts and cause joint failure.

4. Insufficient Joint Clamp Force

The majority of bolted joints rely on the clamping force, which is generated by the torquing or tensioning of bolts to sustain the forces which are applied.

The inclusion of a gasket in a joint to prevent leakage is only effective as long as there is sufficient clamp force generated by the bolts to allow effective sealing. With forces applied to the joint, the forces are transmitted by friction as a result of the clamping force generated by the bolts, leading to a secure bolted connection. Using tools such as HTL’s hydraulic torque wrenches or tensioners can provide accurate torque and tension values, ensuring an even clamping force.

5. Excessive Bearing Stress

Bolts are typically made from high-strength steels, which when fully tightened, exert high clamp force onto the joint. The area directly under the bolt head or nut face sustains the high bearing stress.

If a maximum stress limit for the joint material is exceeded, then deformation occurs over a period of time, which leads to the extension being lost in the bolt, resulting in the clamp force subsequently being reduced.

Bolts transfer force between the connected members, one of the ways bolts transfer force is called bearing.

The bearing method assumes that bolts contact the side of a hole and there is a compressive force between the bolt and the side of the hole. The magnitude of this compressive force is limited by the strength of the material to handle the force.

MEASURES THAT CAN BE TAKEN TO PREVENT BOLT FAILURES:

● Assessing the design of the component or the structure upon which it is going to be used, thereby accurately calculating the amount of force that would be acting on the bolt.

● Assessing the environment where the bolt is going to be used, and applying the right coatings to avoid corrosion.

● Ensuring that proper heat treatment of the bolt is done.

● The fastener’s plating should be carefully designed to avoid hydrogen embrittlement.

● A designer should select the right thread design for the project; it is more preferable to choose a metric coarse thread fastener than a fine thread one, as the possibility of thread damage is significantly less.

Conclusion

Yes, bolts are still magic and we need to understand how they fail so that we can prevent failures in our designs.  Knowing how to diagnose the five failure modes of fasteners is a valuable tool in and of itself.  Being able to accurately predict bolt behavior, by calculations and statistical analysis, might just impress your manager.  We all use fasteners in some way shape or form, so you need to know how to apply them properly. For more details about Resin Anchor Bolts manufacturers in China. Visit our website https://www.jfrockbolt.com

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What is rock bolt mine support?

Rock bolt mine support is a key technology in coal mining. Rock bolt mine support materials play a vital role in rock bolt mine support technology. Supporting materials with superior performance are the necessary prerequisite for giving full play to rock bolt mine support effect and ensuring roadway safety. Today, we will introduce the relevant precautions for the use of anchor rods, so that you can have a better understanding of anchor rods. 

(1) The tail of anchor rod is the most complex and easily damaged part in the whole rod body. The stress analysis of bolt thread section is carried out, and it is found that the stress concentration of thread section is 2-3 times locally due to diameter change Because the spherical rotation center between the tray and the ball pad is unreasonable, self-locking occurs between the two spherical surfaces, which makes the stress of the anchor bolt deteriorate sharply and even break. 

(2) Tension-bending-torsion, tension-shearing-torsion, and combination of tension-bending-shearing-torsion are common stress states in the process of underground anchor installation, and the stress increases closer to the fixed end, so the most unfavorable position is the fixed end.

(3) When the installation angle of anchor rod is too large and the tensile stress reaches a certain value, long-term loading will cause the thread section at the tail of anchor rod to bend and crack or even break; When the pre-tightening torque is greater than 600N'm, the composite stress of the bolt is close to the yield stress of the material, and the bolt cracks from the bend first, and then the crack expands, causing the bolt to break before reaching the breaking force.

(4) Some optimization schemes are put forward, such as vertical setting of corner bolt, redesign of self-aligning ball pad, full-length anchoring of pre-stressed bolt, and adjustment of pre-tightening torque of bolt to 400N.m, so as to reduce the influence of harmful force on the rod body.

If you have any need, please feel free to ask for advice or leave us a message on the website. We believe that with your advice and help, we will do better.

Hebei Jiufu Industrial and Mining Parts Co., Ltd.It is a manufacturer specializing in the supply of supporting materials for coal mining, construction engineering and large-scale concrete projects. It mainly produces self-drilling bolts, friction bolts, glass fiber reinforced plastic solid bolts, Post-TensioningBar, resin bolts and other coal mine engineering support We export 12,000 tons of materials a year, with annual sales of 50 million U.S. dollars. Supporting materials are exported to more than a dozen countries and regions including the Philippines, Thailand, and Russia. We are one of China's important anchor material manufacturers and exporters.

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How to Improve Mining Safety?

Underground sites such as mines and tunnels are tough and dangerous work environments and mining tunnel support related equipment is essential as a small oversight can turn into a huge problem, especially when faced with difficult situations.

Due to the challenging conditions inherent to the site, the level of physical and mental preparation required, as well as the ability to react in challenging situations, are all very important factors.

There are many prevailing uncertainties and unknowns when dealing with the underground. These variables can range from minor inconveniences to major challenges for tunnel designers. A short list of some of these issues includes:

1. the most important uncertainties when dealing with any underground project

2. the geology of the area will determine the feasibility and cost of the project

3. the engineering properties of the rock may change, sometimes dramatically, over a wide range of conditions, particularly time, season, rate, and direction of loading.

4. Groundwater is the most difficult parameter to predict and the most troublesome during construction.

5. Drilling cores is the most commonly used method to determine subsurface conditions, and in the most detailed surveys, typical projects recover less than 0.0005% of the tunnel excavation volume, with significant uncertainty.

Therefore, in the more dangerous working environment of mining, mining tunnel support equipment is essential, such as: cone rock bolt volcanic plates and reinforced mesh for coal mine support and protect. The role of the butterfly rock anchor volcano plate is to transfer the thrust generated by the nut locking torque to the top surface, generating the initial anchoring force, while transferring the pressure from the top surface to the roadway. The anchor rods generate working resistance and work together to reinforce the surrounding rock. Reinforcing mesh is a kind of mesh made of high carbon steel wire, stainless steel wire and other materials, welded by high-tech technology, because of its high precision and good quality, it can play a role in supporting and protecting the coal mine in mining work, if you want to know more, please feel free to contact us.

So what should underground workers do to ensure safety in such dangerous situations?

1. Adapt to local altitude and temperature in advance: Many mines such as Peru are located at high altitude, so it is recommended to properly adapt to the environment to avoid plateau reactions and lack of oxygen. In other mines such as Russia, temperatures can drop to around -30 degrees Celsius, while in countries such as South Africa, temperatures can soar to over 40 degrees Celsius: try to acclimatize to the local climate before doing physical work.

2. Rest and avoid alcohol: Make sure you get a good night's sleep and avoid alcohol and any prescription drugs that may impair your ability. Some underground mining and construction operations will have medical examinations and tests such as spirometry, stress tests, blood and urine tests, and even breath analyzers to ensure that all operators are performing their jobs perfectly.

Check your protective equipment: It is important to check that your protective kit is complete and in working order: coveralls, harnesses, helmets, gloves, glasses, boots, etc.

3. Make sure your lights are in proper working order: Your lights are one of the most important pieces of kit in the mine. Not only does it improve visibility for the carrier, but it also allows other operators to see you and will often find a signal code to indicate whether it is safe to perform certain operations (such as moving forward or backward). Make sure you still have enough batteries to get you through your workday.

4. Familiarize yourself with oxygen escape devices: This kit may be critical to your survival in an emergency. The breathing apparatus provides oxygen for use in extreme situations such as fires or landslides. Knowing how to use it is absolutely paramount: misuse can lead to serious injuries, such as esophageal burns.

5. Pack your kit properly when using transport: For underground mining transport, make sure you don't have loose, dangling equipment that could get stuck in the rock and cause an accident.

Remember escape routes and shelters: Make sure you remember the layout of the site, including the location of key escape routes and shelters, or 6. the location of other emergency rooms in the immediate vicinity in case of an emergency.

Stay calm but stay alert: Underground construction sites often see many different jobs going on at the same time: there may be several pieces of equipment working together, and together they make a lot of noise, as well as drilling and blasting jobs. It is important to remain calm but alert.

7. Follow the mine's safety measures: Each mine is a separate world and is subject to its own set of rules and procedures designed to best suit the specific needs of that mine. Make sure you know what they are and implement them, especially in case of emergency.

8. Ensure your own safety before helping others: Operators are always trained to take care of themselves first and must ensure their own safety before they can help other team members in an emergency.

Are you interested in learning more about mining tunnel supports for sale and how they can benefit you? Contact us today to secure an expert consultation!If you want to know more information about anchor bolts, Resin Anchor Bolts manufacturers in China, Resin Anchor Bolts Suppliers in China. please contact us at https://www.jfrockbolt.com. We will provide professional answers.

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How Does Anchor Bolt Work?

An anchor bolt is a type of fastener that is used to secure objects or structures to concrete or masonry surfaces. It consists of a long rod with a head at one end and threads at the other end, and is typically made of steel or another strong and durable metal.

Anchor bolts work by providing a secure and stable connection between the object or structure being anchored and the concrete or masonry surface. To install an anchor bolt, a hole is first drilled into the concrete or masonry surface, and the anchor bolt is inserted into the hole. The threads on the end of the anchor bolt are then used to secure it in place by either using a nut and washer or by using a chemical adhesive.

Once the anchor bolt is securely in place, it provides a strong and stable connection that can support the weight of the object or structure being anchored. This is particularly important for structures that are subjected to high loads or forces, such as bridges, buildings, and other large structures.

In summary, anchor bolts work by providing a secure and stable connection between an object or structure and a concrete or masonry surface. They are inserted into a hole in the surface and secured in place using threads, a nut and washer, or a chemical adhesive, and are able to support the weight of the object or structure being anchored.

If you want to know more information about anchor bolts,Resin Anchor Bolts manufacturers in China, Resin Anchor Bolts Suppliers in China. please contact us at https://www.jfrockbolt.com. We will provide professional answers.

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In mining, a rock bolt is a long anchor bolt, for stabilizing rock excavations, which may be used in tunnels or rock cuts. This bolt is installed in a hole drilled into the rock, and is intended to improve the stability of the rock and prevent it from falling or collapsing.

One way to install rock bolts is through the use of a "rock split set bolt," which is a type of bolt that is designed to be used in situations where the rock is too hard or abrasive to be drilled using traditional methods. Instead of drilling a hole for the bolt, the rock split set bolt is inserted into a pre-existing crack or fissure in the rock and is then expanded using mechanical force, creating a secure anchor point.

There are several different types of rock split set bolts, each with its own unique features and benefits.                    

Some Common Types Include:

Resin Bolts

These bolts are made from a high-strength, corrosion-resistant material and are typically used in underground mining operations. They are installed using a resin cartridge, which is injected into the bolt and expands when it comes into contact with water, creating a secure anchor point.

Friction Bolts

Friction bolts are made from a flexible material, such as high-density polyethylene, and are designed to create a secure anchor point through friction alone. They are typically used in situations where the rock is too hard or abrasive to be drilled using traditional methods.

Split Set Bolts

Split set bolts are made from a high-strength, corrosion-resistant material and are designed to be inserted into a pre-existing crack or fissure in the rock. They are then expanded using mechanical force, creating a secure anchor point.

The primary role of rock bolts is to provide stability and support to rock excavations, such as tunnels and rock cuts. They are used to prevent rock from falling or collapsing, which can be especially important in underground mining operations where the risk of rockfall is high. Rock bolts are also used to stabilize slopes and prevent landslides, as well as to reinforce concrete structures.

In summary, the role of rock bolts, and specifically rock split set bolts, is to provide stability and support to rock excavations, preventing rockfall and improving the overall safety of the excavation site. These bolts are especially useful in situations where the rock is too hard or abrasive to be drilled using traditional methods, and are an essential part of many mining operations. For more information, please contact us. We will provide professional answers.