Apparatus, excavator, and method for resin infusion

Abstract

An apparatus for injecting grout material, an excavator, and a method for injecting grout resin into a plurality of boreholes. The apparatus (27) includes an injector head (17) provided with a mixing device (18), both of which are insertable into the borehole (7) by means of a flexible supply hose (26). The injector head includes a valve assembly (25) mounted within the distal end of the supply hose.

Description

[Technical Field]

[0001] The present invention relates to a device for injecting grout resin into drilled holes to reinforce rock masses. More specifically, the solution relates to delivering a bulk liquid resin material.

[0002] The invention further relates to a mining machine equipped with a device for injecting grout material and to a method for reinforcing a rock face by injecting grout material into a plurality of drilled holes.

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

[0004] In mines, construction sites, and other work areas, there is a need to reinforce rock faces, thereby ensuring their safety and suitability for their intended purposes. A common method for rock reinforcement is to inject a resin material into a borehole. Several different systems exist for inserting the resin material. One known solution is disclosed in U.S. Patent Publication No. 2011 / 168398(A1). However, this injection method has been shown to include several disadvantages. Summary of the Invention

[0005] It is an object of the present invention to provide a new and improved apparatus for delivering resin material into a drilled hole. The present invention further relates to a new and improved mining machine and method for delivering resin material during reinforcement of a rock face.

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

[0007] The mining machine according to the invention is characterized by the characterizing features of the second independent claim on the device.

[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 involves injecting a mass of resin in fluid form into the borehole before inserting a rock bolt into the borehole. The grout resin is injected using an apparatus including an injector head insertable into the borehole and a mixing device. The apparatus further includes a fluid inlet arrangement connected to the injector head for supplying a resin-based component A and a resin catalyst B to the injector head. The mixing device is configured to mix the supplied resin-based component A and catalyst B together. The injector head and the mixing device are supplied together into the borehole during the injection process. This supply is carried out using a flexible supply hose that is also configured to provide a jacket on the supply line of the fluid inlet system. The injector head includes a valve assembly for controlling the supply of the grout material. The valve assembly is positioned inside the supply hose, so that the supply hose also functions as a tubular jacketing element for the valve assembly. In other words, the distal end of the supply hose is provided with an internal valve assembly or unit.

[0010] Furthermore, in the disclosed solution, the supply hose is fed into the borehole for the duration of the resin supply regimen and is removed from the borehole when the resin supply is complete. In this way, the supply hose is only temporarily inside the borehole and is not left in the borehole. The supply hose and the syringe head should be used multiple times for multiple drillings. In other words, the syringe head provided with the valve module and the mixing device, and the supply hose are not single-use devices. Furthermore, the syringe head provided with the valve module and the mixing device, and the supply hose are all separate physical elements with respect to the rock bolt.

[0011] An advantage of the disclosed solution is that the internal valve assembly does not increase the diameter of the supply system being fed into the borehole. A further advantage is that the valve assembly is surrounded by the covering supply hose, which allows the supply system to move easily axially inside the borehole. The disclosed solution is particularly advantageous for conditions where the borehole is prone to collapse and it is difficult to pull back the supply system.

[0012] A further advantage of the disclosed solution is that it can be of simple, robust and less expensive construction when compared to known solutions. The disclosed solution can be implemented in different rock drilling rigs and reinforcement machines. The system can also be easily retrofitted to existing mining devices.

[0013] According to one embodiment, the supply hose is flexible to allow the supply hose to flex, and the cross-sectional profile of the supply hose will temporarily deform during axial movement if necessary. However, the supply hose is relatively stiff in the axial direction to allow the supply hose to be pushed or pulled axially inside the drilled hole. The outer surface of the supply hose has a low coefficient of friction. This feature, in turn, facilitates the supply of the supply system and allows the supply system to be withdrawn even from a damaged drilled hole.

[0014] According to one embodiment, the flexible supply hose is made of a low-friction polymer material. The supply hose then adapts to the variations in the shape and dimensions of the proposed drilling hole. The supply hose can be made of, for example, polyethylene (PE) or polyethylene medium density (PEM).

[0015] According to one embodiment, the largest cross-sectional dimension of the device corresponds to the outer diameter of the supply hose, in other words all other parts of the device have a smaller or equal diameter compared to the supply hose.

[0016] According to one embodiment, the inner diameter of the supply hose is 30-50 mm. The outer diameter of the valve assembly or module is dimensioned according to the inner diameter of the supply hose.

[0017] According to one embodiment, the disclosed valve assembly includes a body having at least one expandable fastening element on an outer surface thereof configured to be pressed against an inner surface of a supply hose. This installation is simple and quick to perform and does not require any preparation or manipulation of the supply hose.

[0018] According to one embodiment, the expandable fastening element comprises at least one resilient ring-shaped element, which is axially compressed so as to expand radially. This installation is simple and reliable.

[0019] According to one embodiment, the expandable fastening element comprises a series of O-rings, the number of which may be, for example, between 2 and 5. O-rings are inexpensive and robust components.

[0020] According to one embodiment, the expandable fastening element comprises at least one locking ring with a tapered surface configured to move radially and expand when pressed axially with another tapered surface. Alternatively, there may be radially protruding locking tips for anchoring to the inner surface of the supply hose.

[0021] According to one embodiment, the disclosed valve assembly and mixing device are separate elements connected in axial series with an adapter element attached between the valve assembly and the mixing device. In other words, the injector head comprises two functional modules and a connecting adapter element between the two functional modules that facilitates easy removal and change of different types of mixing devices. In this way, mixing devices can be easily changed depending on the resin material used, as well as changes in temperature and ambient conditions.

[0022] According to one embodiment, the mixing device protrudes axially from the distal end of the supply hose. The mixing device is then easy to connect and disconnect, which makes it easy to replace the mixing device or module.

[0023] According to one embodiment, the adapter element is positioned inside the supply hose, and the joint between the adapter and the mixing device is then surrounded and covered by the supply hose.

[0024] According to one embodiment, the adapter element projects axially from the distal end of the supply hose, in other words at least a part of the adapter is outside the end of the supply hose, so that the connection surface of the adapter is visible and connectable.

[0025] According to one embodiment, the adapter element is a separate part that is attached to the valve assembly. There may be a threaded joint or an easy connection between the adapter element and the valve module.

[0026] According to one embodiment, the adapter element is an integral and non-separate part of the valve module, in other words, the adapter is formed directly on the front end of the valve module.

[0027] According to one embodiment, the adapter element comprises a central axially projecting portion, the distal end of which is provided with a tapered sealing surface followed by a connecting thread.

[0028] According to one embodiment, the outer surface of the adapter element body is sealed against the inner surface of the supply hose. There may be one or more sealing elements disposed on the adapter element body. The sealing elements may be, for example, O-rings or lip seals.

[0029] According to one embodiment, the mixing device may be provided with an outer sleeve with an outer diameter corresponding to the outer diameter of the supply hose. The outer sleeve or sheath may be made of the same material as the supply hose. The outer sleeve may be made of a polymeric material. Furthermore, the outer sleeve may be a separate tubular piece that is pressed onto the mixing device, or the outer sleeve or sheath may be made on the mixing unit using a sheath casting method.

[0030] According to one embodiment, the disclosed valve assembly comprises a plurality of control valves for selectively opening and closing at least a resin base component supply line, a resin catalyst supply line, and at least one solvent medium supply line for cleaning the injector head.

[0031] According to one embodiment, the control valves are spring-loaded check valves. These valves are small, simple, reliable and inexpensive.

[0032] According to one embodiment, the control valves mentioned above are hydraulically controlled valves, for example pilot valves, which allow for more versatile fluid supply control.

[0033] According to one embodiment, the injector head is a grout resin delivery tool, whereby the tool is removed from the drilled hole once resin delivery is complete and before a separate rock bolt is delivered into the drilled hole filled with grout resin.

[0034] According to one embodiment, the mixing device comprises a threaded surface, a spiral, a labyrinth, or a correspondingly shaped surface so that the two separate resin component fluid streams fed thereto are mixed to form one homogenous resin mass. The mixing device or element connected to the injector head is a static mixer with multiple non-moving mixing elements or surfaces to mix the fed components together before being discharged from the injector head. The mounting of the mixing device is designed for easy and quick replacement and cleaning, if necessary.

[0035] According to one embodiment, the injector head is connected to three supply lines.

[0036] According to one embodiment, the injector head is connected to four or more supply lines. There may be two different supply lines for the different resin base components A1 and A2, one supply line for the resin catalyst B, and one supply line for the solvent or cleaning agent. If the valve module is equipped with a pressure-controlled pilot valve, an additional control line is required to provide control pressure to the valve module. The above-mentioned base resin components A1 and A2 may have different curing times when the resin components A1 and A2 are mixed with the catalyst B. The catalyst B is a curing agent for the chemical reaction that starts the resin from a liquid to a solid.

[0037] According to one embodiment, the apparatus comprises a solvent supply system configured to supply a solvent medium for cleaning the injector head and the mixing device, the purpose of which is to prevent blockages in the event of breaks between the injection sections of the drilled hole.

[0038] According to one embodiment, the resin material mixed in the mixing device is washed out of the injector head with a solvent medium. The system can be cleaned by extruding the mixed material out of the mix head, out of the drilled hole, or onto the top of the drilled hole immediately after the actual grout resin material has been dispensed. In this way, the system can be cleaned and idled between processing multiple holes.

[0039] According to one embodiment, the solution relates to a mobile mining machine comprising a mobile platform, at least one boom movably connected on the platform, and a device for injecting grout resin into the borehole. Furthermore, at the distal end of the boom there is at least one bolting unit for feeding rock bolts into the borehole after the grout resin has been injected. The boom is provided with a feeding device for moving an injection head of the injection device into the borehole. The device for injecting grout resin is according to the features and embodiments disclosed herein.

[0040] According to one embodiment, after the grout material has been injected, the borehole may be loaded with rock bolts, rock anchors, cables or corresponding elongated metallic reinforcing elements. Thus, there are several alternative rock reinforcement materials that can be installed inside the borehole.

[0041] According to one embodiment, the solution relates to a method for injecting grout resin into multiple boreholes. The method includes inserting an injector head into the boreholes. The grout resin is mixed using a mixing device of the injector head. A resin-based component A and a resin catalyst B are supplied to the injector head using a fluid inlet arrangement with multiple supply lines. The supplied resin-based component and resin catalyst are mixed into a resin mixture inside the borehole using the mixing device. After injection is completed, the injection head is removed from the borehole. Only after that is a metallic rock reinforcement attached inside the borehole. The method further includes feeding the injector head into the borehole using a flexible supply hose surrounding the supply lines of the fluid inlet arrangement. The supply of resin material to the mixing device is controlled using a valve assembly attached inside the distal end of the supply hose. The supply hose thus provides a covering for at least the supply lines and the valve assembly, allowing them to move easily axially inside the borehole.

[0042] The above disclosed embodiments and features may be combined to form a suitable solution having the required features of the above.

[0043] Some embodiments are described in more detail in the accompanying drawings. [Brief explanation of the drawings]

[0044] [Figure 1] 1 is a schematic side view of a rock drilling device intended for underground excavation and rock reinforcement. [Figure 2] FIG. 1 is a schematic side view of an arrangement for delivering grout material into a drilled hole. [Figure 3] FIG. 1 is a schematic diagram showing some features of reinforcement measures for rock faces. [Figure 4] FIG. 10 is a schematic side view of the drilled hole after it has been filled with resin material. [Figure 5] FIG. 5 is a schematic side view of the drilling of FIG. 4 after the rock bolt has been installed. [Figure 6] 1 is a schematic side view of an apparatus for injecting grout material into a drilled hole. [Figure 7] 1 is a schematic side view of a valve assembly and a supply hose intended to receive a fluid supply hose; [Figure 8] 1 is a schematic side view of a valve assembly provided with an integrated adapter head and connected to a fluid supply line; [Figure 9] FIG. 1 is a schematic side view of a module including a valve assembly and a separate adapter component. [Figure 10] FIG. 10 is a schematic side view of another module with different control valves and mounting means. [Figure 11] FIG. 1 is a schematic side view of an injector head with a mixing unit protruding from a supply hose. [Figure 12] 1 is a schematic side view of an injector head in which the mixing unit is surrounded by a covering sleeve element. FIG. [Figure 13] FIG. 1 is a schematic side view of an injector head with a mixing unit partially inside a supply hose. DETAILED DESCRIPTION OF THE INVENTION

[0045] For clarity of explanation, the figures show simplified versions of some embodiments of the disclosed solutions, in which like reference numbers identify like elements.

[0046] FIG. 1 shows a rock drilling rig, which is an example of an excavator 1. The rock drilling rig includes a movable platform 2 and at least one boom 3 connected to the platform 2. At the distal end of the boom 3 is a drilling or bolt insertion unit 4. The unit 4 may include a supply beam 5 and a rock drill 6 supported on the supply beam 5. A drilling tool can be connected to the rock drill 6. The rock drill 6 includes at least a rotation device for rotating the drilling tool about a longitudinal axis of the drilling tool. The rock drill 6 and boom 3 may be rotated to drill boreholes 7 in walls 8 and ceilings 9 of tunnels and other underground spaces for installing reinforcing rock bolts. The unit 4 may also include a bolting unit 10 and an apparatus 11 for supplying a grout resin mixture. The rock drill 6, bolting unit 10 and resin supply device 11 may be connected to the drilling unit 4 so that they can be indexed to the central axis of the drill hole 7, or all or some of them may be connected to the drilling unit 4 so that they are mounted on a dedicated boom or other support structure. At the distal end of the boom 3 there is at least one supply device 12 for moving the devices 6, 10, 11 relative to the distal end of the boom 3. Furthermore, on the loading platform 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.

[0047] FIG. 2 shows an apparatus 27 for inserting a resin material into a drilled hole 7 having an opening 7a and a bottom 7b. A syringe head 17 equipped with a mixing device 18 is inserted into the drilled hole 7. The syringe head 17 is connected to a fluid inlet arrangement 19 including a first supply line 20, a second supply line 21, and an optional third supply line 22. The first supply line 20 is for component A, while the second supply line is dedicated to component B. The third supply line 22 is for supplying a solvent agent S; however, if either line 20 or 21 is used for solvent supply, the system may not include the third line 22. The supply lines 20-22 may be hoses or tubes. In FIG. 2, a resin mixture 23 is supplied through the syringe head 17 and the mixing device 18 to the bottom 7b of the drilled hole 7. The system or apparatus 27 is simultaneously retracted (R) during injection.

[0048] 2 further discloses that the injector head 17 of the device 27 includes a valve assembly 25 mounted inside a supply hose 26. The supply hose 26 also encloses the supply lines 20-22. The injector head 17 is movable using the supply hose 26.

[0049] Figure 3 discloses the steps involved in reinforcing the rock face. These issues have already been discussed herein above.

[0050] FIG. 4 discloses that the drilled holes 7 are filled with a resin mixture 23 .

[0051] In Figure 5, the rock bolt 24 is forced into the drilled hole 7 so that it is inside the resin mixture 23 which hardens and locks the rock bolt 24. The rock bolt 24 can be tightened using a screw means so that the desired pre-tension can be achieved.

[0052] Figure 6 discloses an apparatus 27 provided with a flexible supply hose 26 having a valve assembly 25 at its distal end. The valve assembly 25 is provided at its front end with an adapter element 28 for connecting a mixing device. The adapter element may protrude axially from the supply hose 26 and may include easy connection means. Figure 6 further discloses a supply port 29 or connector for connecting the supply line 20 to the valve assembly 25.

[0053] FIG. 7 discloses a supply hose 26 which may be a flexible tubular element made of a polymeric material, such as a plastic material, with good outer frictional properties.

[0054] 8 discloses the injector head 17 previously mounted inside the supply hose. The outer surface of the body of the injector head 17 is provided with a sealing element 30 and a fastening element 31.

[0055] In Figures 6 and 8, adapter element 28 is an inseparable part of valve assembly 25, whereas in Figures 9-13, adapter element 28 is shown as being a separate module attached to the front end of valve assembly 25.

[0056] 9 discloses that the injector head 17, and more particularly the valve assembly 25, may comprise a body having an expandable fastening element 32 on its outer surface configured to be pressed against the inner surface of the supply hose 26. The fastening system may comprise one or more O-rings 33 arranged to expand radially when pressed axially with the fastening system.

[0057] 10, there is a wedge-shaped element 34 or a corresponding laterally or radially protruding element to provide the required clamping force. This element may be spring-loaded or may be actuated, for example, using a screw element. This clamping system may be on the body of the adapter element 28.

[0058] In Figure 9 the valve assembly comprises a spring loaded check valve 35, whereas in Figure 10 there is a pressure controlled pilot valve 36. In the latter case there is a pilot control line 37 for transmitting control pressure to a controller 38 and further to the valve 36 to operate or control the valve 36.

[0059] Figure 11 discloses a solution in which the mixing device 18 is outside the supply hose 26. In Figure 12 there is an outer sleeve 39 arranged to surround the mixing device 18. In Figure 13 the mixing device 18 is partly inside the supply hose 26. Obviously in all cases the external dimensions of the mixing device do not exceed the external dimensions of the supply hose 26.

[0060] The drawings and associated description are intended only to illustrate the concepts of the invention, which may vary in their details within the scope of the claims.

Claims

1. A device (27) for injecting grout resin into a drilled hole (7) for reinforcing a rock mass, said device (27) being for supplying a fluid material in bulk; an injector head (17) inserted into said drilled hole (7); 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); an elongated tubular covering element surrounding said fluid inlet arrangement (19); Equipped with the injector head (17) is provided with a mixing device (18) for mixing the supplied resin base component (A) and the resin catalyst (B) together, whereby the mixing device (18) is configured to be sent into the drilling hole (7) together with the injector head (17) and the covering element; the injector head (17) comprises a valve assembly (25) positioned inside a flexible supply hose (26) that serves as the tubular covering element; a grout resin supply tool configured to have the injector head (17) removed from the drilled hole (7) after the supply of the resin catalyst (B) is completed and before a separate rock bolt (24) is supplied into the drilled hole filled with the grout resin (23); The apparatus (27) is characterized in that the valve assembly (25) comprises a plurality of control valves (35, 36) for selectively opening and closing at least a resin base component supply line (20), a resin catalyst supply line (21), and at least one solvent medium supply line (22) for washing the injector head (17).

2. 2. The device according to claim 1, wherein the valve assembly (25) comprises a body having at least one expandable fastening element (32, 33) on its outer surface configured to be pressed against an inner surface of the supply hose (26).

3. 3. Apparatus according to claim 1 or 2, characterized in that the valve assembly (25) and the mixing device (18) are separate elements connected in axial succession with an adapter element (28) mounted between them.

4. 4. The device according to any one of claims 1 to 3, characterized in that the valve assembly (25) comprises a plurality of spring-loaded check valves (35).

5. 5. Device according to any one of claims 1 to 4, characterized in that the supply hose (26) is made of a polymeric material.

6. 6. Apparatus according to any one of claims 1 to 5, characterized in that the mixing device (18) is provided with an outer sleeve (39) whose outer diameter corresponds to the outer diameter of the supply hose (26), the outer sleeve (39) being made of polymeric material.

7. 7. Apparatus according to any one of claims 1 to 6, characterized in that the mixing device (18) is configured to project axially from the distal end of the supply hose (26).

8. 8. Device according to any one of claims 1 to 7, characterized in that the largest cross-sectional dimension of the device (27) corresponds to the outer diameter of the supply hose (26).

9. A movable loading platform (2), at least one boom (3) movably connected to the carrier (2); a device (11, 27) for injecting grout resin (23) into the drilled hole (7); at least one bolting unit (10) at the distal end of the boom (3) for delivering rock bolts (24) into the drilled holes (7) after the grout resin (23) has been injected; A mining machine (1), wherein the boom (3) is provided with a feeding device (12) for moving an injector head (17) of the device (11, 27) inside the drill hole (7), A mining machine (1), characterized in that the device (11, 27) for injecting the grout resin (23) is a device according to any one of claims 1 to 8.

10. 1. A method for injecting grout resin into a plurality of drilled holes, comprising: Inserting an injector head (17) inside said drilled hole (7); Providing a mixing device (18) in said injector head (17); feeding a resin base component (A) and a resin catalyst (B) into said injector head (17) using a fluid inlet arrangement (19); mixing the supplied resin base component (A) and the resin catalyst (B) into a resin mixture (23) inside the drilled hole (7) using the mixing device (18); and removing the injector head (17) from the borehole (7) before completing injection and inserting a metallic rock reinforcement (24) inside the borehole (7), feeding the syringe head (17) into the drilled hole (7) using a flexible supply hose (26) surrounding the supply lines (20, 21, 22) of the fluid inlet arrangement (19); and 10. The method of claim 1, further comprising controlling the supply of said resin-based component (A) to said mixing device (18) with a valve assembly (25) mounted within the distal end of said supply hose (26).

11. 11. The method of claim 10, further comprising selecting the mixing device (18) and removably attaching it to the valve assembly (25) using an adapter element (28).

12. A method as described in claim 10 or 11, further comprising selectively opening and closing at least a resin base component supply line (20), a resin catalyst supply line (21), and at least one solvent medium supply line (22) for cleaning the injector head (17) by means of a plurality of control valves (35, 36) of the valve assembly (25).

Images