Intelligent rock bolt driver

Abstract

A drive sleeve 1 for installing ground reinforcement anchor bolts, wherein the drive sleeve includes a rotation sensor 2 for measuring the rotation of the drive sleeve 1, wherein the drive sleeve 1 includes a processing unit 3 configured to receive signals from the rotation sensor 2 and to derive rotation data related to the number of revolutions that the drive sleeve 1 has rotated based on the signals from the rotation sensor 2.

Description

Technical Field

[0001] This disclosure relates to rock anchors for reinforcing formations (such as rock strata), and more particularly to techniques for monitoring the installation of such anchors, especially techniques for monitoring the rotation of a nut or similar object attached to the outer end portion of the anchor. Background Technology

[0002] Formations such as rock formations or strata are typically reinforced using rock bolts. For example, rock bolts are commonly used to reinforce tunnel roofs and stabilize rock walls, slopes, and dikes. Depending on the type of formation to be reinforced, various types of rock bolts or anchors are used.

[0003] A common type of rock bolt is a hydraulically expandable rock bolt, which has an expandable body that is driven into the formation and subsequently expands by introducing a pressurized medium, causing the expandable body to press against the borehole wall, thereby engaging the formation. A hydraulically expandable rock bolt is known from CZ 25706U1.

[0004] Another type of rock bolt is the friction bolt. This type of rock bolt can be driven into the formation using a drive device such as a drilling rig. Mechanically expandable bolts consist of an elongated, expandable outer body (sometimes called a split tube) and a central rod extending from a nut-set tail portion to a front portion within the outer body. The front portion is operatively connected to an expansion mechanism for expanding the outer body when the central rod rotates.

[0005] When installing mechanically expandable rock bolts in the formation, the drive unit is operated to repeatedly impact the outer body of the bolt, thereby forcing the outer body into the formation. When the bolt is driven sufficiently deep into the formation, it expands due to the rotation of the nut, which causes the center rod to rotate, resulting in the expansion mechanism causing the outer body to expand. The nut can be a blind-hole nut, allowing it to be screwed first onto the threads of the tail portion of the center rod, where the center rod eventually descends to its lowest point in the blind-hole nut, thus preventing further relative rotation between the center rod and the blind-hole nut. This allows torque to be applied to the nut and further to the center rod to tighten the bolt's expansion mechanism. Other devices are also feasible to prevent co-rotation between the center rod and the nut, such as threaded locking fluid or shear pins, where a standard nut with a through hole can be used instead of a blind-hole nut.

[0006] Some friction bolts include an outer body but no expansion mechanism, in which the bolt is forced into the formation by press fitting to anchor it in the formation.

[0007] For many types of rock anchors, it is advantageous to rotate the blind hole nut after the anchor is driven into the formation, thereby increasing the adhesion strength between the anchor and the formation.

[0008] Non-expandable anchor bolts (such as resin anchor bolts) may also require rotation after insertion by rotating the nut attached to the tail of the anchor bolt.

[0009] AU2010223134B2 discloses a friction anchor that can expand mechanically.

[0010] Sometimes, operators installing rock bolts do not rotate the blind hole nut after driving the bolt into the formation; instead, they remove the drive mechanism from the blind hole nut. This effectively means the bolt is not installed correctly.

[0011] Manually inspecting and tightening multiple rock bolts in the formation is time-consuming and error-prone, and improper installation of rock bolts is dangerous because parts of the formation may collapse unintentionally.

[0012] Preferably, each nut should be rotated a predetermined number of turns, or to a predetermined torque. Rotating the nut too few times may result in insufficient anchor expansion to engage the formation with a sufficient force. On the other hand, rotating the nut too many times may cause the formation to crack, thereby reducing the formation's strength.

[0013] Sometimes, mining machines carrying drive sleeves are equipped with torque control devices that allow the operator to set a predetermined target torque to be applied to the drive sleeve for rotating the nut of a rock anchor bolt. However, even after the anchor bolt has been driven into the formation, the operator may still forget to start rotating the drive sleeve.

[0014] Therefore, an improved device is needed to facilitate the proper installation of rock anchors. Summary of the Invention

[0015] The purpose of this invention is to improve the control of rock anchor installation to ensure that the drive sleeve has been fully rotated to properly install each rock anchor.

[0016] According to a first aspect of the invention, this objective is achieved by an actuator sleeve for installing ground-reinforced anchor bolts. The actuator sleeve includes a rotation sensor for measuring the rotation of the actuator sleeve. Furthermore, the actuator sleeve includes a processing unit configured to receive signals from the rotation sensor and to derive rotation data related to the number of revolutions the actuator sleeve has made based on the signals from the rotation sensor.

[0017] As the actuator sleeve rotates, a rotation sensor measures the sleeve's rotation and sends a signal. This signal is received by a processing unit, which extracts rotation data related to the number of revolutions the actuator sleeve has made. Therefore, this actuator sleeve can control its operation based on the knowledge of the number of revolutions it has made since the anchor bolt installation began. By integrating the rotation sensor into the actuator sleeve, rotation data can be obtained independently of the type of machine to which the actuator sleeve is attached. Thus, the actuator sleeve enables a plug-and-play method for measuring the rotation of installed anchor bolts and can be used with any existing machine carrying this new actuator sleeve to monitor the correct installation of ground reinforcement anchor bolts.

[0018] Rotation data may include data describing the average rotational speed over a predetermined time period, data describing the number of revolutions the drive sleeve has made at one or more specific points in time, or data describing whether the drive sleeve has rotated at all.

[0019] Typical examples of rotational data are the number of revolutions the drive sleeve has made, the average rotational speed, or acceleration data. Both average speed and acceleration data can be used to derive the number of revolutions the drive sleeve has made.

[0020] Sensors may include gyroscopes and / or accelerometers and / or inclinometers.

[0021] Furthermore, the driver sleeve may further include a wireless transmitter or transceiver configured to transmit signals including rotation data.

[0022] By transmitting signals that include rotation data, it is possible to remotely receive rotation data, enabling remote entities to monitor the rotation of ground-reinforced anchor bolts in real time without any wired or direct physical contact with the rotating actuator sleeve.

[0023] According to a second aspect of the invention, this objective is also achieved by a method for monitoring the installation of ground-reinforced anchor bolts, wherein the method includes receiving rotation data from one or more actuator sleeves and, according to alternative a) recording the rotation data to a data carrier, or according to alternative b) deriving a rotation value from the rotation data describing the number of rotations the actuator sleeve has undergone, issuing a first signal if the rotation value exceeds a lower threshold that defines a minimum number of rotations the actuator sleeve should undergo for proper installation, and / or, if the rotation value exceeds the lower threshold, creating or updating a data record on the data carrier, the data record including an identifier of the currently rotating anchor bolt and data indicating that the anchor bolt has rotated the required number of rotations.

[0024] According to this method, rotational data is obtained from one or more actuator sleeves and used to determine whether a signal is issued indicating that the ground-reinforced anchor bolt has rotated sufficiently to be considered correctly installed. Specifically, the method includes determining a rotational value describing the number of revolutions the actuator sleeve has rotated. This can be as simple as using the number of revolutions already explicitly given in the rotational data, but may require calculating the number of revolutions based on average rotational speed and / or acceleration data. Once the number of revolutions the actuator sleeve has rotated is determined, it is compared to a threshold.

[0025] Furthermore, if the actuator sleeve has been rotated sufficiently, data logs can be created or updated, allowing individuals or systems to easily consult the data records on the data carrier to check if the anchor bolt has been installed correctly. Therefore, once the actuator sleeve is removed from the reinforced anchor bolt inserted into the ground, it can be used to install another anchor bolt, with the data records on the data carrier used to keep track of which anchor bolts have been installed correctly.

[0026] The method may further include: issuing a second signal if the rotation value exceeds an upper limit threshold, the upper limit threshold defining the maximum number of rotations the drive sleeve can rotate for proper installation, and / or, if the rotation value exceeds the upper limit threshold, creating or updating a data record on a data carrier, the data record including an identifier of the currently rotating anchor and data indicating that the anchor has over-rotated.

[0027] Furthermore, the method may further include recording the installation duration of each anchor bolt, and creating or updating a data record on a data carrier if the rotation value exceeds a lower threshold, the data record including the installation duration of the currently rotating anchor bolt and the identifier of the currently rotating anchor bolt.

[0028] Therefore, the electronics of the actuator sleeve can also be used to track the installation duration of each ground reinforcement anchor by separately recording the start and stop times of anchor installation. Any one or more suitable durations can be measured for each anchor, such as from the start of driving the anchor into the ground and / or from the start of rotating the actuator sleeve. Furthermore, the end of the duration can be the time when it is detected that the anchor has rotated more than a threshold number of revolutions, and / or the end of the duration can be the time after the anchor has been inserted into the hole in the ground but before the actuator sleeve begins to rotate. For example, the duration can be used for benchmarking and statistical purposes to improve installation efficiency and quality.

[0029] In addition, the method may include receiving torque data from a torque sensor configured to measure the torque applied to the drive sleeve, and deriving rotational resistance data based on the torque data and rotational data.

[0030] By deriving rotational resistance data in this way, it can be verified whether the rotational resistance suddenly decreases as the actuator sleeve rotates further. This typically indicates a problem during installation, such as cracks forming around the reinforced anchor bolt. Furthermore, the rotational resistance data enables tracking based on resistance and the current ground type.

[0031] Torque sensors can be integrated with machines that carry drive sleeves, such as drilling rigs.

[0032] Machines carrying drive sleeves for installing ground reinforcement anchors are typically equipped with torque adjustment devices. These devices allow the torque applied to the drive sleeve to be set appropriately based on experience. Therefore, torque data can be obtained directly or indirectly from the machine carrying the drive sleeve. By adjusting the method of installing ground reinforcement anchors to also include steps to derive the rotational resistance data for each installed anchor, a better understanding of the installation of each anchor can be achieved, and measures can be taken to correct any deviations. For example, if the rotational resistance suddenly decreases after a prolonged period of increase, this may be because the anchor has cracked the ground, causing it to no longer reinforce the ground as intended. Then, any appropriate measures can be considered, such as replacing the ground reinforcement anchor or adding additional anchors nearby.

[0033] The method may further include continuously comparing the current rotational resistance with a lower resistance threshold, and a) issuing a third signal if the comparison indicates that the rotational resistance has fallen below the lower resistance threshold, and / or b) creating or updating a data record on a data carrier if the comparison indicates that the rotational resistance has fallen below the lower resistance threshold, the data record including an identifier of the currently rotating anchor and data indicating that the torque has fallen below the lower resistance threshold.

[0034] By continuously monitoring whether the rotational resistance decreases more than expected, appropriate measures can be taken, such as replacing ground-reinforced anchor bolts or adding additional anchor bolts nearby. A lower resistance threshold is used to determine the deviation of interest. The lower resistance threshold can be a dynamically calculated threshold or a predetermined threshold.

[0035] A lower resistance threshold can be continuously calculated by recording the maximum value of the rotational resistance based on rotational resistance data, and then the lower resistance threshold is calculated as a predetermined fraction of the maximum value of the rotational resistance data. Since slight fluctuations in rotational resistance are normal, simply looking for instantaneous drops in torque is insufficient, as this may create the false impression that maximum torque has been reached and over-rotation has begun. Instead, a lower resistance threshold should be used, which can be dynamically calculated as a predetermined fraction of the maximum value, rather than based on a predetermined lower threshold.

[0036] The emitted first, second, and / or third signals can be presented using audio communication devices such as speakers or visual communication devices such as light sources or display units.

[0037] By using audio or visual communication devices to present the first signal, the operator controlling the installation of the reinforced anchor bolts can easily understand the signal, allowing the operator to know when the anchor bolts are correctly installed.

[0038] According to a third aspect of the invention, this objective is also achieved by a monitoring system for monitoring the installation of ground-reinforced anchor bolts. The monitoring system includes the actuator sleeve as described above and a computer program product configured to perform the methods described above.

[0039] The monitoring system may further include mobile computing devices, such as smartphones or mobile terminals, for running computer program products. Attached Figure Description

[0040] Figure 1 A simplified side view of the drive sleeve according to the first embodiment is shown, where dashed lines indicate the central recesses for receiving the anchor bolt and attaching it to the mining machine, respectively. Detailed Implementation

[0041] The following description, with reference to the accompanying drawings, describes a drive sleeve according to a first embodiment and its use with a mining machine. The drive sleeve 1 is used to install ground reinforcement anchors in the formation. The drive sleeve includes a rotation sensor 2 for measuring the rotation of the drive sleeve 1. The drive sleeve 1 also includes a processing unit 3 configured to receive signals from the rotation sensor 2 and to derive rotation data related to the number of revolutions the drive sleeve 1 has made based on the signals from the rotation sensor 2. The rotation sensor is an electronic rotation sensor.

[0042] Rotation data includes data describing the average rotational speed over a predetermined time period, data describing the number of revolutions that the drive sleeve 1 has rotated at one or more specific time points, or data describing whether the drive sleeve 1 has rotated at all.

[0043] Typical examples of rotational data are the number of revolutions the actuator sleeve has made, average rotational speed, or acceleration data. Both average speed and acceleration data can be used to derive the number of revolutions the actuator sleeve has made, if needed. Installing such a rotational sensor on the actuator sleeve allows for the direct replacement of many existing types of actuator sleeves, enabling monitoring of anchor bolt installation by studying the rotational data provided by the sensor. The rotational data can be analyzed in real time or as part of a post-installation procedure to ensure safe and timely anchor bolt installation.

[0044] The rotation sensor 2 includes a gyroscope and / or an accelerometer and / or an inclinometer. The gyroscope, accelerometer, and / or inclinometer are configured to take into account the position / or orientation of the rotation sensor relative to the rotation axis of the actuator sleeve to determine rotation data.

[0045] The driver sleeve 1 further includes a wireless transmitter or transceiver 4 configured to transmit signals including rotation data. However, alternatively or additionally, the driver sleeve may include a data carrier (such as a computer memory) configured to store rotation data in addition to transmitting signals with rotation data.

[0046] By transmitting signals that include rotation data, it is possible to remotely receive rotation data, enabling remote entities to monitor the rotation of ground-reinforced anchor bolts in real time without any wired or direct physical contact with the rotating actuator sleeve.

[0047] A second aspect of the invention relates to a method for monitoring the installation of ground-reinforced anchor bolts. The method includes receiving rotational data from one or more actuator sleeves 1 according to the invention, and recording the rotational data onto a data carrier. The data carrier may be integrated into the actuator sleeve, or the actuator sleeve may be located remotely from the data carrier, such as in a separate storage device. Examples of storage devices are cloud storage devices, handheld terminals, or computer systems onboard mining machines.

[0048] Additionally or alternatively, the method may include a step of deriving rotational values ​​from rotational data, which describe the number of revolutions that the drive sleeve 1 has rotated.

[0049] Additionally, the method may include: issuing a first signal if the rotation value exceeds a lower threshold, the lower threshold defining the minimum number of revolutions the drive sleeve 1 should rotate for proper installation. Furthermore, the method may include: creating or updating a data record on a data carrier if the rotation value exceeds the lower threshold, the data record including an identifier of the currently rotating anchor and data indicating that the anchor has rotated the required number of revolutions.

[0050] The method may further include: issuing a second signal if the rotation value exceeds an upper threshold, the upper threshold defining the maximum number of rotations that the drive sleeve 1 can rotate for proper installation. Alternatively or additionally, the method may include: creating or updating a data record on a data carrier if the rotation value exceeds the upper threshold, the data record including an identifier of the currently rotating anchor and data indicating that the anchor has over-rotated.

[0051] A single data carrier can be used for all the data storage needs mentioned, or alternatively, multiple data carriers can be provided.

[0052] The method also includes the following optional steps: recording the installation duration of each anchor bolt, and if the rotation value exceeds a lower threshold, creating or updating a data record on the data carrier, the data record including the installation duration of the currently rotating anchor bolt and the identifier of the currently rotating anchor bolt.

[0053] The installation time for each anchor bolt is measured from the point when rotation is considered to have begun until the installation of the anchor bolt is considered to be complete.

[0054] In addition, the method includes the following optional steps: receiving torque data from a torque sensor configured to measure the torque applied to the drive sleeve 1, and deriving rotational resistance data based on the torque data and rotational data 4.

[0055] Here, the torque sensor used is a permanent sensor integrated with the machine carrying the drive sleeve (i.e., the mining machine). However, alternatively, the torque sensor can be located elsewhere, such as integrated with the drive sleeve or installed between the mining machine and the drive sleeve.

[0056] The method further includes continuously comparing the current rotational resistance with a lower resistance threshold. A third signal is issued once the comparison indicates that the rotational resistance has fallen below the lower resistance threshold. Alternatively or additionally, if the comparison indicates that the rotational resistance has fallen below the lower resistance threshold, a data record is created or updated on the data carrier. The data record includes an identifier of the currently rotating anchor bolt and data indicating that the torque has decreased below the lower resistance threshold.

[0057] The lower limit resistance threshold is continuously calculated as a predetermined fraction of the maximum value of the rotational resistance data. However, a suitable lower limit resistance threshold can be derived using any other appropriate statistical calculation.

[0058] Instead of using information from a torque sensor to determine if an anchor bolt is too easily rotated, rotation data can be used to reach the same conclusion. In this case, the method also includes continuously monitoring the current rotation speed and comparing it to a predetermined upper limit rotation speed threshold, and issuing a third signal if the comparison indicates that the rotation speed exceeds the upper limit rotation speed threshold. Alternatively or additionally, if the comparison indicates that the rotation speed exceeds the upper limit rotation speed threshold, a data record is created or updated on a data carrier, the data record including an identifier of the currently rotating anchor bolt and data indicating that the rotation speed has exceeded the upper limit rotation speed threshold.

[0059] The transmitted first signal, second signal, and / or third signal are presented using an audio communication device in the form of a speaker and a visual communication device in the form of a display unit. In other embodiments, the auditory and / or visual presentation of the transmitted signal may be omitted.

[0060] In one aspect, the technology is provided in the form of a monitoring system for monitoring the installation of ground-reinforced anchor bolts, wherein the monitoring system includes the drive sleeve 1 as described above and a computer program product configured to perform the methods described above.

[0061] The system may further include mobile computing devices, such as smartphones or mobile terminals, for running computer program products.

Claims

1. A driver sleeve (1) for installing ground reinforcement anchor bolts, wherein, The actuator sleeve includes a rotation sensor (2) for measuring the rotation of the actuator sleeve (1), wherein the actuator sleeve (1) includes a processing unit (3) configured to receive signals from the rotation sensor (2) and to derive rotation data related to the number of revolutions the actuator sleeve (1) has made based on the signals from the rotation sensor (2), characterized in that the rotation sensor (2) includes a gyroscope and / or an accelerometer and / or an inclinometer, and wherein the gyroscope, accelerometer and / or inclinometer is configured to determine the rotation data taking into account the position / or orientation of the rotation sensor relative to the rotation axis of the actuator sleeve, and The driver sleeve further includes a wireless transmitter or transceiver (4) configured to transmit a signal including the rotation data.

2. The driver sleeve according to claim 1, wherein, The rotation data includes data describing the average rotation speed over a predetermined time period, data describing the number of revolutions the driver sleeve (1) has made at one or more specific time points, or data describing whether the driver sleeve (1) has rotated.

3. A computer-implemented method for monitoring the installation of ground-reinforced anchor bolts, wherein, The method includes: Receive rotational data from one or more drive sleeves (1) according to any one of claims 1-2, and a) Record the rotation data onto a data carrier, and b) Derive from the rotation data a rotation value describing the number of revolutions the drive sleeve has rotated. If the rotation value exceeds a lower threshold, a first signal is issued, the lower threshold defining the minimum number of rotations the driver sleeve (1) should rotate for proper installation, and / or If the rotation value exceeds the lower threshold, a data record is created or updated on the data carrier. The data record includes an identifier of the currently rotating anchor and data indicating the required number of rotations the anchor has completed.

4. The method of claim 3, further comprising: If the rotation value exceeds an upper threshold, a second signal is issued, the upper threshold limiting the maximum number of rotations the driver sleeve (1) can achieve for proper installation, and / or If the rotation value exceeds the upper limit threshold, a data record is created or updated on the data carrier, the data record including an identifier of the currently rotating anchor and data indicating that the anchor has over-rotated.

5. The method of claim 4, further comprising: The installation duration of each anchor bolt is recorded, and if the rotation value exceeds the lower threshold, a data record is created or updated on the data carrier, the data record including the installation duration of the currently rotating anchor bolt and the identifier of the currently rotating anchor bolt.

6. The method according to any one of claims 3 to 5, further comprising: Torque data is received from a torque sensor configured to measure the torque applied to the drive sleeve (1). Rotational resistance data is derived based on the torque data and the rotational data.

7. The method according to claim 6, wherein, The torque sensor is integrated with the machine that carries the drive sleeve.

8. The method of claim 7, further comprising: Continuously compare the current rotational resistance with the lower resistance threshold, and a) If the comparison indicates that the rotational resistance has decreased below the lower resistance threshold, a third signal is issued, and / or (b) If the comparison indicates that the rotational resistance has decreased below the lower resistance threshold, a data record is created or updated on the data carrier, the data record including an identifier of the currently rotating anchor and data indicating that the torque has decreased below the lower resistance threshold.

9. The method of claim 8, further comprising: The maximum value of the rotational resistance is recorded based on the rotational resistance data, wherein the lower limit resistance threshold is continuously calculated as a predetermined fraction of the maximum value of the rotational resistance data.

10. The method according to any one of claims 3-5, further comprising: Continuously monitor the current rotation speed and compare the current rotation speed with a predetermined upper limit rotation speed threshold, and a) If the comparison indicates that the rotational speed exceeds the upper limit rotational speed threshold, a third signal is issued, and / or b) If the comparison indicates that the rotational speed exceeds the upper limit rotational speed threshold, a data record is created or updated on the data carrier, the data record including an identifier of the currently rotating anchor and data indicating that the rotational speed has exceeded the upper limit rotational speed threshold.

11. The method according to any one of claims 3-5, wherein, The first, second, and / or third signals emitted are presented using audio communication devices or visual communication devices.

12. The method according to claim 7, wherein, The machine in question is a drilling rig.

13. The method according to claim 11, wherein, The audio communication device is a speaker.

14. The method according to claim 11, wherein, The visual communication device is a light source or a display unit.

15. A monitoring system for monitoring the installation of ground reinforcement anchor bolts, wherein, The monitoring system includes a driver sleeve (1) according to any one of claims 1-2 and a computer program product configured to perform the method according to any one of claims 3-14, the monitoring system further including a mobile computing device for running the computer program product.

16. The monitoring system according to claim 15, wherein, The mobile computing device is a mobile terminal.

17. The monitoring system according to claim 16, wherein, The mobile computing device is a smartphone.

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