Method and apparatus for extracting a hard metal body from a component

Abstract

A method for recovering at least one hard-metal body from a part, the method comprising first clamping the part in a clamping device and then simultaneously or cyclically heating and vibrating the part to detach the at least one hard-metal body from the part. Also, an apparatus for recovering at least one hard-metal body from a part having an axial axis, the apparatus comprising a vibration device for vibrating the part perpendicular to the axial axis, a clamping device for positioning the part such that the hard-metal body vibrates perpendicular to the axial axis, and at least one heating device for vibrating the part and heating the part simultaneously.

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for extracting at least one hardmetal body from a component, in particular, but not exclusively, to the extraction of at least one used hardmetal body from a mined or construction component. [Background technology]

[0002] Cemented carbide bodies are widely used in components such as drill tools, cutting tools, mining and processing tools, and high wear resistant parts. However, when the cemented carbide body wears out too much it becomes ineffective and the part is therefore discarded. Both tungsten and cobalt in the cemented carbide are strategic rare metals and therefore there is great value and environmental benefit in being able to extract the cemented carbide body from the part. Cemented carbide scrap is considered an important secondary resource of cobalt and tungsten metals. Therefore, when these parts are discarded, they are collected and processed for recycling to recover the scrap cemented carbide which can then be recycled to produce new parts.

[0003] Known extraction methods, such as that disclosed in US Pat. No. 4,170,513, involve recovering the hard metal bodies from the worn parts by using a sulphuric acid bath to erode some of the steel surrounding the insert, then heating the part in a furnace, and then subsequently vibrating the heated part to knock out the insert. However, there are several problems with this type of process. The extraction time is long and not all the bodies are extracted, which means that either the process needs to be repeated, which adds further processing time and costs, or the recovery yield is not as high as desired. A further problem is the need to manually transfer the heated parts from the furnace to the vibrating device, which is a health and safety hazard.

[0004] It is therefore desirable to find a new method for extracting hardmetal bodies from parts that can clean up to all parts in one process, does not involve manual handling of heated parts, is safer, faster, and results in a higher extraction yield. Summary of the Invention

[0005] It is an object of the present invention to provide a method and apparatus for extracting a hardmetal body from a component, and an apparatus for use in said method, which is safer, faster, more environmentally friendly and results in a higher extraction yield.

[0006] These objects are achieved in a first aspect of the present application, which provides a method for recovering at least one hardmetal body from a component, comprising the steps of: a) first clamping the part in a clamping device, and then b) simultaneously or cyclically heating and vibrating the part to detach at least one hard metal body from the part; This is achieved by providing a method comprising:

[0007] Advantageously, by simultaneously or cyclically heating and vibrating the part, the time for at least one hardmetal body to be extracted is much shorter. Typically, a part is fitted with several hardmetal bodies, and using this method the extraction yield of objects from the part is much higher, i.e. the output of recovered hardmetal bodies per hour is increased. A further advantage of this method is that no manual handling of the heated part is required, thus making the recovery process safer. This method works by locally heating the part in the areas where heating is required for the extraction of the hardmetal bodies, thus reducing the required energy input compared to preheating the whole part in a furnace before vibrating it. Furthermore, this method is safer and requires less manpower.

[0008] In one embodiment, induction heating is used to heat the part. Advantageously, induction heating allows for directing the heat to the specific area of ​​the part where the cemented carbide body is attached, thus minimizing the required energy input, making this an energy-efficient process.

[0009] Alternatively, flame heating is used to heat the part. Advantageously, flame heating is a very simple and inexpensive heating method to use.

[0010] In one embodiment, in step b) the part is heated to a temperature of 600-1000°C. Preferably to a temperature of 700-900°C. Advantageously, this temperature range allows the most efficient extraction of the cemented carbide insert from the part without completely melting the steel of the part or using unnecessarily high energy. The temperature to which the part is heated can be measured, for example, using an IR gun. Different parts may require different temperatures. Preferably, the part is heated to the lowest possible temperature.

[0011] In one embodiment, there is an additional step between steps a) and b) where the part is preheated before the simultaneous heating and vibration of the part is performed. Advantageously, the addition of preheating reduces the overall recovery time. Preferably, the preheating temperature is between 600 and 1000°C, more preferably between 700 and 900°C.

[0012] In one embodiment, induction heating is used to preheat the part. Advantageously, induction heating allows for directing the heat to the specific area of ​​the part where the cemented carbide body is attached, thus minimizing the required energy input, making this an energy-efficient process.

[0013] Alternatively, flame heating is used to preheat the part. Advantageously, flame heating is a very simple and inexpensive heating method to use.

[0014] Alternatively, furnace heating is used to preheat the parts.

[0015] In one embodiment, the vibration of the part is controlled by compressed air. Advantageously, this directs more force to the cemented carbide body and therefore means that the cemented carbide body is retrieved from the part in the most time and energy efficient manner.

[0016] Alternatively, the vibration of the part is controlled by an electric motor or any other suitable means.

[0017] In one embodiment, the part is rotated radially and / or axially during step b), so that the part is heated and vibrated while rotating at the same time, which can be particularly advantageous when the part comprises a cemented carbide body that protrudes in multiple directions, for example in the case of a rotating cone.

[0018] According to a second aspect of the present application, there is provided an alternative method for recovering at least one hardmetal body from a component which achieves the above object, comprising the steps of: a) first clamping the part in a clamping device; b) secondly, heating the at least one cemented carbide body using induction heating; and then c) thirdly, vibrating the component to detach at least one cemented carbide body from the component; There are alternative methods, including:

[0019] Advantageously, the use of induction heating to heat the part allows the heating to be directed to the specific area of ​​the part where the hardmetal body is attached, thus minimizing the required energy input, making this a more environmentally friendly, safer, energy and time efficient process.

[0020] In one embodiment, in step b) the part is heated to a temperature of 600-1000°C. Preferably to a temperature of 700-900°C. In one embodiment, the vibration of the part is controlled by compressed air. In one embodiment, the part is rotated radially and / or axially during step b).

[0021] According to a third aspect of the present invention, there is provided an apparatus for recovering at least one hardmetal body from a component having an axial axis, the apparatus comprising: The apparatus includes a vibration device for vibrating the part in a direction having an angle of less than 30° relative to the axial axis, a clamping device for positioning the part so that the cemented carbide body vibrates in a direction having an angle of less than 30° relative to the axial axis, and at least one heating device for heating the part while vibrating the part.

[0022] Advantageously, this apparatus allows the part to be vibrated and heated simultaneously. Furthermore, this set-up means that the part is restricted to only being able to vibrate and move in the most preferred direction, e.g. vertically or in directions having an angle of less than 30°.

[0023] In one embodiment, the clamping device comprises a plate with a drop-shaped opening. Advantageously, this allows a wide range of part sizes and shapes to be held using the same clamping device. The design of the clamping device minimizes movement of the part relative to the clamping device. Additionally, the clamping device allows the center point of the part relative to the heater to remain relatively constant even when different sized parts are clamped, which advantageously means that the heating device does not need to be repositioned when different sized parts are processed, saving processing time.

[0024] In one embodiment, the clamping device includes a threaded fastener. Advantageously, this provides a secure clamp to hold the part in the required position.

[0025] In one embodiment, the vibration device is an air-controlled vibration device. Advantageously, this directs more force to the hard-metal body, meaning that the hard-metal body is therefore retrieved from the part in the most time and energy efficient manner.

[0026] In one embodiment, the apparatus further comprises a vertical block and at least one guide rod arranged between the vibration device and the clamping device, which advantageously guides the vibrations perpendicular to the axial axis.

[0027] In one embodiment, the heating device is an induction heater, also known as a radio frequency heater. Advantageously, the induction heating device can be placed where the part needs to be locally heated in the correct location to remove the hard metal body in the most time and energy efficient manner. Furthermore, the induction heating device does not allow any heat to diffuse into the vibration device, and all heat can be directed to the part.

[0028] Specific embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0029] [Figure 1] FIG. 1 is a schematic diagram of the apparatus. [Diagram 2] FIG. 1 is a schematic diagram of a preferred embodiment of a clamping device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] FIG. 1 shows a schematic diagram of an apparatus 8 for recovering at least one hard-metal body 2 from a part 4 having an axial axis 40. The apparatus 8 comprises a vibration device 10 for vibrating the part 4 in any rotational direction, more preferably perpendicular to the axial axis 40, in a direction having an angle of less than 30°, preferably less than 20° to the axial axis 40, a clamping device 6, also known as a fixture, for positioning the part 4 so that the at least one hard-metal body 2 vibrates in any rotational direction, more preferably perpendicular to the axial axis 40, in a direction having an angle of less than 30°, preferably less than 20° to the axial axis 40, and at least one heating device 12 for heating the part 4 simultaneously with vibrating it or periodically. The clamping device 6 is typically made of steel, is fixed to a frame 36 and is suitable for clamping either a cold part 4 or a preheated part 4. The clamping device 6 may also be movable, so that the part 4 can be rotated as required, the rotation being controlled using a programmable rotator.

[0031] Preferably, the vibration device 10 is a compressed air controlled vibration device 10. The pressure and flow rate of the compressed air may be controlled to optimize the vibration so that the energy is directed towards the removal of the at least one hard metal body 2. Preferably, a PLC controlled valve is used to optimize the vibration. Alternatively, the vibration device 10 may be controlled using an electric motor or via any other suitable means. Alternatively, the vibration device 10 is an electric motor or any other suitable vibration device.

[0032] The cleaning process to extract the insert is performed by vibrating the clamping device 6 and the part 4 in a force and speed controlled oscillatory motion by the vibration device 10 in a steered and controlled pulse process.

[0033] Preferably, the vibration device 10 is attached to the clamping device 6, such that vibration of the part 4 is performed via the clamping device 6. Alternatively, the vibration device 10 can be directly connected to the part 4, such that vibration of the part 4 is performed directly on the part 4.

[0034] Optionally, there is at least one vertical block 26 and at least one guide rod 28 disposed between the vibration device 10 and the clamping device 6. Typically, the vertical block is made of steel or aluminum, but may be made of any other suitable material capable of directing the vibrations in a preferred direction.

[0035] Optionally, a damping element 38 , such as a disc spring or a rubber damper, may be disposed axially between the vibration device 10 and the at least one vertical block 26 to reduce the impact of vibrations on the frame 36 .

[0036] Preferably, the heating device 12 is an induction heater, also known as a radio frequency heater. Induction heating is the process of heating a conductive object by electromagnetic induction via heat generated in the object by eddy currents. An induction heater consists of an electromagnet and an electronic oscillator that passes high frequency alternating current (AC) through the electromagnet. The rapidly alternating magnetic field penetrates the object and generates electric currents in the conductor called eddy currents. The eddy currents flowing through the resistance of the material heat the material by Joule heating.

[0037] The heating device 12 is movable both vertically and horizontally, either manually or automatically.

[0038] Induction heaters typically have a circular or U-shaped coil, but the coil can be shaped into any other suitable shape or size to fit the geometry of the part 4 being processed. Typically, induction heaters comprise a single coil, but multiple coils can also be used. The heating device 12 is preferably held in place using a heating device holder 14. The heating device holder 14 can be movable, either manually or automatically, so that the heating device 12 can be positioned in the correct position relative to the part 4 such that an optimal distance between the heating device 12 and the part 4 is achieved, i.e., as close as possible to achieve the most efficient heating without creating a short circuit. Alternatively, the heating device 12 can be held in place by hand.

[0039] Alternatively, the heating device 12 can be a flame heater that can be positioned either by hand or using a heating device holder 14. For example, acetylene and compressed air flame heaters can be used, this type of flame heater producing a flame that is hot enough to heat the part 4 to the required temperature but not so hot that the steel from the part 4 melts, which may make extraction of the cemented carbide 2 insert more difficult, although any other type of flame heater can be used. Alternatively, a combination of induction heating and flame heating can be used.

[0040] A safety cage (not shown) may be provided to guide at least one hot extracted cemented carbide body 2 into a funnel (not shown) and lower it into a collection box (not shown), which may be insulated.

[0041] 2 shows a preferred embodiment of a clamping device 6 comprising a plate 16 with a teardrop-shaped opening 18 and a threaded fastener 42, in this case a nut 20 welded onto the plate 16 to receive a clamping bolt 22 with a hardened central pin 24 for pressing into the part to hold it firmly in place. The hardened central pin 24 is free to rotate upon application of force from the clamping bolt 22. Alternative designs of the threaded fastener 42 or any other suitable non-threaded clamping device 6, such as a lever-type device, could also be used.

[0042] It is preferred that the heat input to the clamping device 6 is kept to a minimum. The clamping device 6 may therefore be water cooled.

[0043] A method for recovering at least one cemented carbide body 2 from a part 4, comprising the steps of: a) clamping the part 4 in a clamping device 6; and then b) simultaneously or cyclically heating and vibrating the part 4 to release the at least one cemented carbide body 2 from the part 4.

[0044] In one embodiment, heating and vibration can be performed either simultaneously. In another embodiment, heating and vibration can be performed cyclically. By cyclically, it is meant that the part 4 is first heated to a target temperature range specific to that part 4, then heating is paused, and vibration may be started immediately or shortly thereafter, such as less than one minute, then vibration is paused, and heating may be resumed immediately or shortly thereafter, such as less than one minute, etc., until all the cemented carbide bodies 2 are recovered. Alternatively, a combination of simultaneous and cyclic heating and vibration can be used. At least one cemented carbide body 2 can be a mining insert, a cutting pick, or a blade-shaped cemented carbide unit, including but not limited to any other cemented carbide body 2 attached to the part 4.

[0045] Part 4 is typically a mining or construction part and may be, for example, a tophammer drill bit or foot, a down-the-hole (DTH) drill bit or foot, a cone bit, a cutting pick, a riser drilling shell, a rotary drill cone or foot, a horizontal directional drill (HDD) bit or foot, or a reamer block foot, but may be any other part 4 having at least one cemented carbide body 2 attached thereto. Part 4 is typically made from steel, and once all cemented carbide bodies 2 have been removed, the steel from part 4 may also be recycled.

[0046] The recovery method may be used on a component 4 having at least one cemented carbide insert 2 pressed or brazed in place or held in any other way.

[0047] Typically, this recovery process is used to recover at least one cemented carbide body 2 from a used part 4, which is then commonly referred to as a dull part 4. However, if desired, the method can also be used to remove at least one cemented carbide body 2 from an unused new part 4.

[0048] The part 4 is vibrated perpendicularly to the axial axis 40 and the part is clamped in place with the cemented carbide bodies 2 facing downwards. For parts 2 with cemented carbide bodies 2 arranged in multiple orientations, e.g. rotating cones or HDD cones, it may be necessary to rotate the part 4 so that all the cemented carbide bodies 2 are arranged downwards at some points.

[0049] Typically, in step b), the part 4 is heated to a temperature of 600-1000° C., more preferably to a temperature of 700-900° C. The part 4 may continue to be heated until all the cemented carbide body 2 has been recovered.

[0050] The relative position of the part 4 with respect to the heating device 12 can be changed during operation to heat different areas of the part 4 as needed to optimize recovery of the at least one hardmetal body 2 from the part 4. If induction heating is used, the coil should be placed as close to the part 4 as possible to achieve the most efficient heating, closer than necessary for minimum heat input with the fastest extraction time, but not so close that it touches and shorts out. The size and shape of the coil should be selected to maximize the efficiency of heating.

[0051] A programmable rotation device may be used such that the rotation is preprogrammed to match the geometry of the particular part being processed.

[0052] Optionally, there is an additional step between steps a) and b), where the part 4 is preheated. If a preheating step is included, this can be performed with the cemented carbide body 2 either face down or face up, i.e. either in the same position as in step b) or inverted. The preheating step is preferably performed using induction heating, but can also be performed using flame heating or in a furnace. If required, it is also possible to use a combination of induction heating, flame heating and furnace heating for preheating. If preheating is used, the part 4 is typically heated to 600-1000°C, preferably 700-900°C.

[0053] At least one recovered hardmetal body 2 can then be collected and dropped into a collection bin (not shown) where it is allowed to cool. Once all hardmetal bodies 2 have been removed, the part 4 is moved to a release position from which it is allowed to drop and cool.

[0054] Alternatively, a method for recovering at least one cemented carbide body 2 from a component 4 includes, first, clamping the component to a clamping device 6, second, heating the at least one cemented carbide body 2 using induction heating, and then, third, vibrating the component 4 to detach the at least one cemented carbide body 2 from the component 4.

[0055] In any of the methods described herein, it is also possible to set up the apparatus 8 such that at least one hardmetal body 4 can be removed simultaneously from multiple parts 4. For example, multiple parts 4 can be fixed to a plate, for example by welding, in order to process them all at once.

Claims

1. A method for recovering at least one hardmetal body (2) from a part (4), comprising the steps of: a) first clamping the part in a clamping device (6), then b) simultaneously or periodically heating and vibrating said part (4) to detach at least one hard metal body (2) from said part (4); A method comprising:

2. The method according to claim 1, wherein induction heating is used to heat the part (4).

3. The method according to claim 1, wherein flame heating is used to heat the part (4).

4. The method according to claim 1, wherein in step b) the part (4) is heated to a temperature of 600 to 1000°C.

5. 2. The method according to claim 1, wherein there is an additional step between steps a) and b), in which the part (4) is preheated before the simultaneous heating and vibration of the part (4) is carried out.

6. The method according to claim 5, wherein induction heating is used to preheat the part (4).

7. The method according to claim 1, wherein the vibration of the part (4) is controlled by compressed air.

8. The method according to claim 1, wherein the part (4) is rotated radially and / or axially during step b).

9. A method for recovering at least one hardmetal body (2) from a part (4), comprising the steps of: a) first clamping the part in a clamping device (6); b) secondly, heating the at least one cemented carbide body (2) using induction heating; and then c) thirdly, vibrating said part (4) to detach at least one cemented carbide body (2) from said part (4); A method comprising:

10. 1. An apparatus (8) for recovering at least one hardmetal body (2) from a part (4) having an axial axis (40), comprising: a vibration device (10) for vibrating said part (4) in a direction having an angle of less than 30° relative to said axial axis (40); a clamping device (6) for positioning said part (4) such that at least one cemented carbide body (2) oscillates in a direction having an angle of less than 30° with respect to said axial axis (40); at least one heating device (12) for vibrating said part (4) and at the same time heating said part (4); An apparatus (8).

11. The clamping device (6), 11. The apparatus (8) of claim 10, comprising a plate (16) having a drop-shaped opening (18).

12. The apparatus (8) of claim 10, wherein the clamping device (6) is provided with a threaded part (42).

13. The apparatus (8) described in claim 10, wherein the vibration device (10) is a compressed air controlled vibration device.

14. The apparatus (8) of claim 10, further comprising a vertical block (26) and at least one guide rod (28) arranged between the vibration device (10) and the clamping device (6).

15. The apparatus (8) of claim 10, wherein the heating device (12) is an induction heater.

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