Equipment, excavators and methods for resin injection

Abstract

The apparatus (11) includes an injector head (17) provided with a mixing device (18), both of which are insertable into a drilled hole (7). The apparatus is for delivering resin mixtures (23a, 23b) having two different curing times. The injector head is connected to a fluid inlet arrangement (19) comprising a common first supply line for the slow-curing and fast-curing resin-based components (A1, A2) and a second supply line for a resin catalyst (B).

Description

[Technical field]

[0001] The present invention relates to an apparatus for injecting grout material into drilled holes when reinforcing rock surfaces with rock bolts. The drilled holes are drilled by a rock drill, then provided with grout material and finally the rock bolts are inserted and fastened. More specifically, the solution concerns the injection of a resin with two different hardening times.

[0002] The invention further relates to an excavator equipped with equipment for injecting grout material and to a method for reinforcing a rock surface. [Background technology]

[0003] The field of the invention is more particularly defined in the preambles of the independent claims.

[0004] In mines, construction sites and other work areas, there is a need to reinforce rock surfaces and thereby ensure their safety and fitness for the intended purpose. A common method for rock reinforcement is rock bolting. In such a reinforcement system, several rock bolts are fastened in the drilled holes by means of grout material. In this way, the rock layers are bonded together and the risk of collapse is reduced. There are several different systems for inserting the grout material. However, current injection means have been shown to include several drawbacks. Summary of the Invention

[0005] It is an object of the present invention to provide a new and improved apparatus for delivering grout material to drilled holes. The present invention further relates to a new and improved excavator and method for delivering grout material in reinforcing rock surfaces.

[0006] The device according to the invention is characterized by the characteristic features of the first independent device claim.

[0007] The mining machine according to the invention is characterized by the characteristic features of the second independent equipment claim.

[0008] The method according to the invention is characterized by the characterizing features and steps of the independent method claims.

[0009] The disclosed solution concept is to inject bulk resin in fluid form into the drilled hole before inserting the rock bolt into the drilled hole. Furthermore, two different resins with different curing times are implemented in the injection. The grouting resin is injected by an apparatus insertable inside the drilled hole and comprising an injector head equipped with a mixing device. The apparatus further comprises a fluid inlet arrangement connected to the injector head for supplying the injector head with the resin base component A1 or A2 and the resin catalyst B. The mixing device is configured to mix with the supplied resin base component A1 or A2 and the catalyst B. The injector head and the mixing device are fed together inside the drilled hole during the injection process. Furthermore, the above-mentioned fluid inlet arrangement comprises two separate supply lines. The first supply line can be alternatively selected for supplying the first base resin component A1 or the second resin base component A2, and the second supply line is for supplying the resin catalyst B. In other words, the fluid inlet arrangement is provided with only two supply lines for supplying the grouting resin material into the drilled hole. The base resin components A1 and A2 have different curing times when mixed with Catalyst B, which is a hardener for the chemical reaction that initiates the change of the resin from a liquid to a solid.

[0010] The advantage of the disclosed solution utilizing only two feed lines for the resin components is that the diameter of the drilled holes can be smaller compared to solutions implementing a larger number of feed lines. Smaller diameter drilled holes can be drilled more effectively, more quickly, and with less energy consumption. The diameter of rock bolts is typically 14mm to 18mm, whereby a relatively small diameter hole is sufficient for the rock bolts. Furthermore, only a small amount of resin is required for grouting because the hole is well adapted to the small bolt diameter mentioned above. The disclosed injector head and feed lines can fit into very small holes whose diameters can be as small as 30 to 35mm. In such small diameter holes, it is difficult to add an additional hose to manage the second component without increasing the pressure drop in the feed.

[0011] A further advantage is that, when the mixing device is in the injector head, the resin base component A1 or A2 is mixed with the resin catalyst B as late as possible before being injected into the drilling holes. This means that only a small amount of resin material is wasted in case the injector head and the mixing device need to be cleaned between injection steps of the drilling holes.

[0012] Furthermore, the disclosed solution provides a system for supplying two resin mixtures with different curing times, so that a drilled hole can be provided with a fast curing resin mixture at the bottom followed by a slow curing resin mixture. The injector heads are simultaneously retracted during the injection process.

[0013] A further advantage of the disclosed solution is its simple and durable construction compared to known solutions provided with complex injection adapters.

[0014] The disclosed solution can be implemented on different rock drilling rigs and bolting jumbos. The system can also be easily retrofitted to existing mining equipment.

[0015] The apparatus is provided with a resin pumping arrangement in which two pumps are provided: there is thus a common first supply pump arranged to alternatively supply the first resin base component A1 or the second resin base component A2 to the first supply line, and further a second supply pump is dedicated to supplying the resin catalyst B to the second supply line.

[0016] According to one embodiment, the first and second feed pumps described in the previous embodiment are positive displacement pumps, the pumps being configured to operate synchronously, so that the volume of the resin-based component A1 or A2 fed relative to the catalyst B fed is substantially constant.

[0017] According to one embodiment, the above mentioned positive displacement pump can be a pump provided with a chamber having a predetermined volume inside which the batch of feed material can be. A piston, plunger or gear element then compresses the material into the feed line. Thus, the pump can be, for example, a piston type pump or a gear pump.

[0018] According to one embodiment, the volumetric feed ratio of the selected resin base component (A1 or A2) to the catalyst B is generally 1:1, but can also take other values ​​such as 2:1, 1:2 or 3:1.

[0019] According to one embodiment, the first feed pump and the second feed pump are powered by a common actuator. The shared actuator may be a motor, and the pumps may be connected on the same output shaft of the motor. The advantage of using one common actuator is that the pumps are automatically driven synchronously. The feed volume ratio of the resin-based component (A1 or A2) and the catalyst B is constant. Then the pumping is easy to control.

[0020] In an alternative solution, the pumps are separately operated pumps but controlled synchronously. The phrase "operating synchronously" means that the pumps can be managed or regulated at the same speed, or alternatively, the pumps can be managed or regulated according to flow measurements in each line.

[0021] The device comprises at least one supply valve for selectively connecting the inlet channel of the common first supply pump to a first container provided for the first resin-based component A1 or to a second container provided for the second resin-based component A2.

[0022] According to one embodiment, the injector head is a grout resin delivery tool, and the tool is removed from the drilled hole when the resin delivery is completed and before a separate rock bolt is fed into the drilled hole filled with grout resin. Thus, the injector head is used several times for several drilled holes, rather than being left inside the drilled hole. In other words, the injector head and the mixer device are not single used devices. Moreover, the injector head and the mixer device are separate from the rock bolt.

[0023] According to one embodiment, the injector head is retracted inside the drilled hole towards the hole opening while injecting the resin mixture. The retraction speed correlates with the resin flow rate and hole size. The retraction speed may also take into account possible cracks, voids, or other spaces that need to be filled.

[0024] According to one embodiment, the borehole can be fitted with rock bolts, rock anchors, cables or corresponding elongated metallic reinforcing elements after the grout material has been injected. Thus, there are several alternative rock reinforcement materials that can be fitted inside the borehole.

[0025] According to one embodiment, the apparatus comprises a solvent supply system configured to supply a solvent medium for flushing the injector head and the mixing device. The purpose of the system is to prevent clogging in situations where there is a lull between injections of drilling holes. The solvent supply system comprises a third pump for pumping the solvent medium from a third container.

[0026] According to one embodiment, the solvent medium provided is a solvent or a grease or a gel (high viscosity) or a water-based mixture.

[0027] According to one embodiment, the resin material mixed in the mixing device is flushed by the solvent medium to the outside of the injector head. The system can be cleaned by pushing the mixed material out of the mixing head, out of the drilled hole, or to the top of the drilled hole immediately after the actual grouting resin material is dispensed. In this way, the system can be cleaned and wait while processing several holes. The solvent mixture is then removed and replaced with a resin mixture by pushing the solvent mixture out of the mixing head, to the bottom of the drilled hole, or to the ground, i.e., outside the drilled hole, before the actual grouting resin material is dispensed.

[0028] According to one embodiment, the solvent supply system comprises a third supply line dedicated to supplying the solvent medium from a third pump to the mixing device.

[0029] According to one embodiment, the solvent supply system can alternatively be connected to the first supply line and / or the second supply line via a solvent valve. Thus, the system utilizes a shared supply line of the resin-based component. This is particularly useful when high viscosity solvents (such as greases or gels) are used, since there is a piston effect in the hose to clean the supply line. Note that the solvent is only supplied for a certain time or volume to clean the mixing device and the injector head. The solvent may also be pumped in an alternative or continuous manner.

[0030] According to one embodiment, the disclosed equipment can be connected to an excavator. The feeder of the excavator is then configured to insert and move the injector head and the mixing device inside the drilled hole.

[0031] According to an embodiment, the disclosed solution also relates to an excavator comprising a mobile carrier, one or more booms movably connected on the carrier, an instrument for injecting grouting resin into the drilled hole, and one or more bolting units at the distal end of the boom for feeding rock bolts or corresponding elongated reinforcements into the drilled hole after the grouting resin has been injected. The boom is provided with a feeding device for moving an injector head of the injection instrument inside the drilled hole. The injection instrument of the excavator follows the mechanism disclosed herein.

[0032] According to an embodiment, the disclosed solution also relates to a method for injecting grout resin into several drilled holes, the method comprising: inserting an injector head inside the drilled holes, providing a mixing device on the injector head, supplying a basic resin component A and a resin catalyst B to the injector head by a fluid inlet arrangement, mixing the supplied basic resin component and the resin catalyst inside the drilled holes by the mixing device to form a resin mixture, starting the injection of the resin mixture at the bottom of the drilled holes, moving the injector head and the mixing device towards the opening of the drilled holes during the injection, completing the injection and removing the injector head from the drilled holes, and installing a metal rock reinforcement inside the drilled holes provided with the grout resin. The method further comprises sequentially injecting two different resin mixtures having different curing times into the drilled holes, providing two resin supply lines on the fluid inlet arrangement, and supplying a first resin-based component A1 and a second resin-based component A2 having different curing times in a selective order through the first supply line. Resin catalyst B is fed simultaneously with the selected base component A1 or A2 through a second feed line.

[0033] According to one embodiment, the aim of the solution is to provide a drill hole with two or more resin sections with different curing times inside the drill hole in order to implement a so-called spring effect of the rock bolt. In this embodiment, the bottom of the drill hole is provided with a shorter curing time and the rest of the drill hole is provided with a longer curing time. If the bottom cures faster, the rock bolt can be fastened before the rest of the resin material cures, thereby pre-tensioning the rock bolt.

[0034] According to one embodiment, the mixing device comprises a screw surface, a helix, a labyrinth or a correspondingly shaped surface for mixing the two separate resin component fluid streams fed to form one homogenous resin mass. The mixing device or element associated with the injector head is a static mixer having several non-moving mixing elements or surfaces for mixing the fed components together before being discharged from the injector head. The structure of the mixing device can be designed such that the above-mentioned mixing elements are easily and quickly replaced and cleaned as needed. The mixing device may comprise a cartridge type mixing element for easy maintenance. Moreover, the mixing device is dimensioned so that it can be inserted inside a small diameter drilled hole.

[0035] According to one embodiment, the disclosed injection system comprises one or more control units for selectively controlling the supply and amount of the required resin components (slow curing resin, fast curing resin, catalyst, inhibitor supply), flushing the supply lines (solvent supply) and controlling the movement of the injector head in the drilled hole (feed and retract). The control unit may be provided with one or more injection sequences and the system may be provided with an automatic operating mode. The control unit may control the resin supply (flow rate) and retract the movement of the injector head depending on the diameter of the drilled hole. In this case, the controllable parameters are at least the flow rate and the movement speed.

[0036] The above disclosed embodiments and features can be combined to form a suitable solution having the above features as required.

[0037] Some embodiments are explained in more detail in the accompanying drawings. [Brief description of the drawings]

[0038] [Figure 1] FIG. 1 is a schematic side view of a rock drilling rig for underground drilling and rock reinforcement purposes. [Diagram 2] FIG. 1 is a schematic side view of a configuration system for supplying grout material to a drilled hole. [Diagram 3] FIG. 1 is a schematic diagram showing some mechanisms for reinforcing means for rock surfaces. [Figure 4] FIG. 13 is a schematic side view of a drilled hole after it has been filled with two types of resin material. [Diagram 5] FIG. 5 is a schematic side view of the drilling of FIG. 4 after the rock bolt has been installed. [Figure 6] FIG. 2 is a schematic diagram of an apparatus for injecting grout material into drilled holes. [Figure 7] FIG. 1 illustrates some principles and mechanisms of rock reinforcement. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] For clarity, the figures show some embodiments of the disclosed solutions in a simplified manner.In the drawings, like reference numbers indicate like elements.

[0040] FIG. 1 shows a rock drilling rig, which is an example of an excavation machine 1. The rock drilling rig comprises a mobile carrier 2 and at least one boom 3 connected to the carrier 2. A drilling unit or bolt insertion unit 4 is provided at the distal end portion of the boom 3. The unit 4 may comprise a feed beam 5 and a rock drill 6 supported thereon. A drilling tool can be connected to the rock drill 6. The rock drill 6 comprises at least one rotating device for rotating the drilling tool about its longitudinal axis. The rock drill 6 and the boom 3 can be swiveled, so that a drill hole 7 can be drilled and a reinforcing rock bolt can be installed in the wall 8 and the ceiling 9 of a tunnel or the like. The unit 4 may also comprise a bolting unit 10 and an equipment 11 for supplying a resin mixture for grouting. The drilling machine 6, the bolting unit 10 and the resin supply equipment 11 may be connected to the drilling unit 4 so that they can be indexed on the central axis of the drill hole 7, or alternatively, all or part of them may be mounted on a dedicated boom or other support structure. At the distal end of the boom 3 there is at least one feeding device 12 for moving the devices 6, 10, 11 relative to the distal end of the boom 3. Furthermore, on the carrier 2 there may be a first container 13 provided for the first resin-based component A1, a second container 14 provided for the second resin-based component A2, a third container 15 for the solvent medium S and a fourth container 16 for the resin catalyst B.

[0041] FIG. 2 discloses a drilled hole 7 provided with an opening 7a and a bottom 7b. Inside the drilled hole 7, an injector head 17 provided with a mixing device 18 is inserted. The injector head 17 is connected to a fluid inlet arrangement 19 comprising a first supply line 20, a second supply line 21 and an optional third supply line 22. The first supply line 20 is a common supply line for components A1 and A2, and the second supply line is dedicated for component B. The third supply line 22 is for supplying the solvent agent S, but if the line 20 or 21 is used for solvent supply, the system may not have the third line 22. The supply lines 20-22 may be hoses or tubes. In FIG. 2, the resin mixture 23 is supplied to the bottom 7b of the drilled hole 7 through the injector head 17 and the mixing device 18. The system is simultaneously retracted in the R direction during injection.

[0042] Figure 3 discloses the steps involved in reinforcing the rock surface. These issues have already been discussed herein above.

[0043] 4 discloses that the drilled hole 7 is filled with two resin mixtures 23a, 23b. The bottom 7b of the drilled hole 7 is injected with the fast curing resin mixture 23b, and the rest of the drilled hole up to or near the opening 7a of the drilled hole 7 is filled with the slow curing resin mixture 23a.

[0044] In Figure 5, the rock bolt 24 is forced into the drilled hole 7 so that its distal end extends into the fast-setting resin mixture 23b mentioned above, which hardens rapidly and locks the end of the rock bolt 24. The rock bolt 24 can then be tightened before the slow-setting resin mixture 23a hardens. In this way, a spring effect can be achieved. The spring effect is indicated by the dashed line 25 between the bottom 7b of the hole and the opening 7a.

[0045] FIG. 6 discloses a resin supply system and equipment 11 for grouting. Many of the features have already been shown and described in the previous figures. There are containers 13-16 for the resin components A1, A2 and B, as well as the solvent S. Also, the injector head 17 inserted inside the drilled hole 7 and provided with the supply lines 20-22 has already been described. However, FIG. 6 shows some additional problems regarding the pumping of the resin components A1, A2, B and the solvent S. The equipment 11 comprises a resin pumping arrangement 26 provided with two pumps 27 and 28. The common first supply pump 27 is arranged to alternatively supply the first resin-based component A1 or the second resin-based component A2 to the first supply line 20. The second supply pump 28 is dedicated to supply the catalyst B to the second supply line 21. Furthermore, the first feed pump 27 and the second feed pump 28 are positive displacement pumps and are configured to operate synchronously, so that the volume of the resin-based component A1 or A2 fed relative to the catalyst B fed is constant. The first feed pump 27 and the second feed pump 28 can be powered by a common actuator 29, such as a motor M. The pumps 27, 28 may be connected to a common output shaft 30 of the motor M. The device 11 comprises at least one feed valve 31 for selectively connecting the inlet channel 32 of the common first feed pump 27 to the first container 13 provided for the first resin-based component A1 or to the second container 14 provided for the second resin-based component A2. The second feed pump 28 is permanently connected to the fourth container 16. There may be a check valve 33 in the resin feed line.

[0046] The apparatus further comprises a solvent supply system 34 configured to supply solvent medium S for flushing the injector head 17 and the mixing device 18. The solvent supply system 34 comprises a third pump 35 for pumping the solvent medium S from the third container 15. The pump 35 can be actuated by an actuator 36, which can be, for example, a motor M. There is a third supply line 22 dedicated to supplying the solvent medium S from the third pump 35 to the mixing device 18.

[0047] A control unit CU is capable of controlling the operation of the disclosed system and associated pumps, actuators and valves.

[0048] FIG. 6 further discloses that the containers 13-16 may be connected to a pressurized or desiccant / vent dryer system 37 to facilitate delivery of their contents.

[0049] It should be noted that the device 11 disclosed in Figure 6 may also be implemented with slightly different components and arrangements. For example, one pump may be dedicated to A1, another pump for A2, and a third pump for B.

[0050] FIG. 7 is a simplified diagram illustrating some of the problems disclosed in this document.

[0051] The drawings and the associated description are intended only to illustrate the concept of the invention. In its details, the invention may vary within the scope of the claims.

Claims

1. 1. An apparatus (11) for injecting grout resin into a drilled hole (7) for rock reinforcement, comprising: said device (11) for supplying a bulk fluid material; a grout resin supplying tool, an injector head (17), inserted inside the drilled hole (7), the tool being removed from the drilled hole (7) when the resin supplying is completed and before a separate rock bolt (24) is fed into the drilled hole (7) filled with the grout resin (23a, 23b); At least one fluid inlet arrangement (19) connected to said injector head (17) for supplying said injector head (17) with a resin base component A and a resin catalyst B. With The injector head (17) is provided with a mixing device (18) for mixing the supplied resin base component A and the supplied resin catalyst B, and the mixing device (18) is configured to be sent into the inside of the drilled hole (7) together with the injector head (17); said fluid inlet arrangement (19) comprises two separate supply lines, a first supply line (20) selectable for the alternative supply of a first resin-based component A1 and a second resin-based component A2 associated with two different curing times, and a second supply line (21) for said resin catalyst B; The device (11) comprises a resin pumping arrangement (26) provided with two pumps, a common first supply pump (27) configured to selectively supply the first resin base component A1 or the second resin base component A2 to the first supply line (20), and a second supply pump (28) is provided exclusively for supplying the resin catalyst B to the second supply line (21); said device (11) comprises at least one supply valve (31) for selectively connecting an inlet channel (32) of said common first supply pump (27) to a first container (13) provided for said first resin-based component A1 or to a second container (14) provided for said second resin-based component A2; An apparatus (11).

2. The first supply pump (27) and the second supply pump (28) are positive displacement pumps and are configured to operate synchronously, so that the volume of the supplied resin base component A1 or A2 relative to the supplied resin catalyst B is constant.

2. The device according to claim 1 ,

3. The first supply pump (27) and the second supply pump (28) are powered by a common actuator (29).

3. The device according to claim 1 or 2, characterized in that

4. The apparatus (11) comprises a solvent supply system (34) configured to supply a solvent medium (S) for flushing the injector head (17) and the mixing device (18). It is characterized by:

4. Apparatus according to any one of claims 1 to 3, wherein the solvent supply system (34) comprises a third pump (35) for pumping the solvent medium (S) from a third container (15).

5. The solvent supply system (34) includes a third supply line (22) dedicated to supplying the solvent medium (S) from the third pump (35) to the mixing device (18).

5. The device according to claim 4, characterized in that

6. Said equipment (11) is controlled by a control unit (CU) and the sequence of insertion between the base resin component and the resin catalysts (A1+B, A2+B) and optionally the solvent (S) is managed according to time or flow rate measurements or pump displacement measurements.

6. The device according to claim 1 ,

7. said device (11) being connectable to a mining machine (1); a feeder (12) of the mining machine (1) configured to insert and move the injector head (17) and the mixing device (18) inside the drilling hole (7); 7. The device according to claim 1, wherein the first and second electrodes are arranged in a first direction.

8. A movable carrier (2); At least one boom (3) movably connected on the carrier (2); A device (11) for injecting grout resin into the drilled hole (7); at least one bolting unit (10) at a distal end of the boom (3) for delivering rock bolts (24) into the drilled holes (7) after the grouting resin (23) has been injected; Equipped with The boom (3) is provided with a feed device (12) for moving an injector head (17) of the equipment (11) inside the drilling hole (7), The device (11) for injecting the grout resin (23) is as claimed in any one of claims 1 to 7. A mining machine (1).

9. A method for injecting grout resin (23) into several drilled holes (7), comprising the steps of: Inserting an injector head (17) inside the drilled hole (7); A mixing device (18) is provided on the injector head (17), and the mixing device (18) is inserted into the inside of the drilling hole (7) together with the injector head (17); Supplying a resin base component A and a resin catalyst B to said injector head (17) by a fluid inlet arrangement (19); mixing the supplied resin base component and the resin catalyst inside the drilling hole (7) by the mixing device (18) to obtain a resin mixture (23); starting the injection of the resin mixture (23) at the bottom (7b) of the drilled hole (7) and moving (R) the injector head (17) and the mixing device (18) toward the opening (7a) of the drilled hole (7) during the injection; completing the injection and removing the injector head (17) from the drilled hole (7); Inserting a metal rock reinforcement material (24) into the inside of the drilled hole (7) in which the grout resin (23) is provided; Including, Injecting two different resin mixtures (23a, 23b) having different curing times sequentially into said drilled holes (7); said fluid inlet arrangement (19) being provided with two supply lines (20, 21), the first supply line (20) being selectable by means of a supply valve (31) for the alternative supply of a first resin-based component A1 and a second resin-based component A2 associated with two different curing times, and the second supply line (21) being for said resin catalyst B; - feeding in a selective order through said first feed line (20) a first resin-based component A1 and a second resin-based component A2 associated with different curing times; supplying the resin catalyst B simultaneously with the selected first resin base component A1 or the selected second resin base component A2 through the second supply line (21); A method comprising:

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