METHOD AND APPARATUS FOR EXTRACTION OF CEMENTED CARBIDE BODIES FROM A COMPONENT

Abstract

A method for recovery of at least one cemented carbide body from a component including the steps of first clamping the component in a clamping device, and then simultaneously or cyclically heating and vibrating the component to dislodge the at least one cemented carbide body from the component. Also provided is an apparatus for the recovery of at least one cemented carbide body from a component having an axial axis, the apparatus including a vibrating device arranged for vibrating the component in a vertical direction with respect to the axial axis, a clamping device arranged for positioning the component so that the cemented carbide bodies are vibrated in a vertical direction with respect to the axial axis, and at least one heating device arranged for heating of the component at the same time as vibrating the component.

Claims

1. A method for recovery of at least one cemented carbide body from a component, the method comprising the steps of: a) first clamping the component in a clamping device; and b) simultaneously or cyclically heating and vibrating the component to dislodge the at least one cemented carbide body from the component.

2. The method according to claim 1, wherein induction heating is used to heat the component.

3. The method according to claim 1, wherein flame heating is used to heat the component.

4. The method according to claim 1, wherein in step b) the component is heated to a temperature of between 600-1000 C.

5. The method according to claim 1, wherein there is an additional step, between steps a) and b) wherein the component is pre-heated before the simultaneously heating and vibrating of the component is performed.

6. The method according to claim 5, wherein induction heating is used to pre-heat the component.

7. The method according to claim 1, wherein the vibration of the component is controlled by compressed air.

8. The method according to claim 1, wherein the component is rotated in a radial and/or axial direction during step b).

9. A method for recovery of at least one cemented carbide body from a component, the method comprising the steps of: a) firstly, clamping the component 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 dislodge the at least one cemented carbide body from the component.

10. An apparatus for recovery of at least one cemented carbide body from a component having an axial axis, the apparatus comprising: a vibration device arranged for vibrating the component in a direction having an angle of less than 30 with respect to the axial axis; a clamping device arranged for positioning the component so that the at least one cemented carbide body is vibrated in a direction having an angle of less than 30 with respect to the axial axis; and at least one heating device arranged for heating the component at the same time as vibrating the component.

11. The apparatus according to claim 11, wherein the clamping device comprises: includes a plate having a drop-shaped opening.

12. The apparatus according to claim 10, wherein the clamping device comprises includes a threaded component.

13. The apparatus according to claim 11, wherein the vibration device is a compressed air-controlled vibration device.

14. The apparatus according to claim 11, further comprising a vertical block and at least one guiding rod positioned between the vibration device and the clamping device.

15. The apparatus according to claim 11, wherein the heating device is an induction heater.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0033] A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which:

[0034] FIG. 1 is a schematic drawing of the apparatus.

[0035] FIG. 2 is a schematic drawing of a preferred embodiment of the clamping device.

DETAILED DESCRIPTION

[0036] FIG. 1 shows a schematic drawing of the apparatus 8 for recovery of at least one cemented carbide body 2 from a component 4 having an axial axis 40. The apparatus 8 comprises a vibration device 10 for vibrating the component 4 in a direction having an angle of less than 30, preferably less than 20, with respect to the axial axis 40 in any rotational direction, more preferably vertically with respect to the axial axis 40; a clamping device 6, otherwise known as a fixture, for positioning the component 4 so that the at least one cemented carbide body 2 is vibrated in a direction having an angle of less than 30, preferably less than 20 with respect to the axial axis 40 in any rotational direction, more preferably vertically with respect to the axial axis 40; and at least one heating device 12 for heating of the component 4 simultaneously or cyclically with vibrating the component 4. The clamping device 6 is typically made of steel and is fixed to a frame 36 and is suitable for clamping either cold or pre-heated components 4. The clamping device 6 could also be moveable, so that the component 4 can be rotated as required, the rotation could be controlled using a programmable rotator.

[0037] Preferably, the vibration device 10 is a compressed air-controlled vibration device 10. The pressure and the flow rate of the compressed air can be controlled to optimise the vibrations so that the energy is directed to removal of the at least one cemented carbide body 2. Preferably, PLC controlled valves are used to optimise the vibration. Alternatively, the vibration device 10 could be controlled using an electric motor or any via any other suitable means. Alternatively, the vibration device 10 is an electric motor or any other suitable vibrating device.

[0038] The cleaning process to extract the inserts is made by vibrating the clamping device 6 and the component 4 in a vibrating movement controlled in force and speed by the vibrating device 10 in a steered and controlled pulsed process.

[0039] Preferably, the vibration device 10 is attached to the clamping device 6, so that the vibration of the component 4 is done via the clamping device 6. Alternatively, the vibration device 10 could be connected directly to the component 4 so that the vibration of the component 4 is done directly to the component 4.

[0040] Optionally, there is at least one vertical block 26 and at least one guiding rod 28 positioned between the vibration device 10 and the clamping device 6. Typically, the vertical block is made from steel or aluminium, but it could be made from any other suitable material that is capable of directing the vibrations in the preferred direction.

[0041] Optionally, a damping element 38, such as disc springs or rubber dampeners may be positioned axially between the vibration device 10 and the at least one vertical block 26 to reduce the impact of the vibrations on the frame 36.

[0042] Preferably, the heating device 12 is an induction heater, otherwise known as a high-frequency heater. Induction heating is the process of heating an electrically conducting object by electromagnetic induction, through heat generated in the object by eddy currents. An induction heater consists of an electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet. The rapidly alternating magnetic field penetrates the object, generating electric currents inside the conductor, called eddy currents. The eddy currents flowing through the resistance of the material heat it by Joule heating.

[0043] The heating device 12 is moveable in both vertical and horizontal directions, either manually or automatically.

[0044] The induction heater typically has a circular or U-shaped coil, but the coil could be moulded to any other suitable shape or size to suit the geometry of the component 4 being treated. Typically, the induction heater comprises a single coil, but multiple coils could also be used. The heating device 12 is preferably held in position using a heating device holder 14. The heating device holder 14 could be moveable, either manually or automatically to be able to position the heating device 12 at the correct location relative to the component 4 so that the optimal distance between the heating device 12 and component 4 is achieved, i.e. as close as possible to be able to achieve most efficient heating without resulting short circuiting. Alternatively, the heating device 12 could be held in position by hand.

[0045] Alternatively, the heating device 12 could be a flame heater, which could either be positioned by hand or using a heating device holder 14. For example, an acetylene and compressed air flame heater could be used, this type of flame heater produces flames that are hot enough to sufficiently heat the component 4 to the required temperature, but not so hot that the steel from the component 4 will melt, which could make the extraction of the cemented carbide 2 inserts more difficult, but any other sort of flame heater could be used. Alternatively, a combination of induction heating and flame heating could be used.

[0046] A safety cage (not shown) can be installed to guide the at least one hot extracted cemented carbide body 2 into a funnel (not shown) and down into a collection box (not shown), which could be insulated.

[0047] FIG. 2 shows a preferred embodiment of the clamping device 6 wherein the clamping device 6 comprising a plate 16 having a drop shaped opening 18; a threaded component 42, which in this case is a nut 20 welded onto the plate 16 for receiving a tightening bolt 22; and wherein the tightening bolt 22 comprises a hardened centre pin 24 for pressing into the component to hold it securely in place. The hardened centre pin 24 can rotate freely around when forces from the tightening bolt 22 is applied. An alternative design for the threaded component 42 or any other suitable non-threaded clamping device 6 e.g. a levered device could also be used.

[0048] It is preferably for the heat input into the clamping device 6 to be kept to a minimum. Therefore, the clamping device 6 could be water cooled.

[0049] The method for recovery of at least one cemented carbide body 2 from a component 4 comprising the steps of: a) clamping the component 4 in a clamping device 6. Then b) simultaneously or cyclically heating and vibrating the component 4 to dislodge the at least one cemented carbide body 2 from the component 4.

[0050] In one embodiment, the heating and vibrating could either be done simultaneously. In another embodiment the heating and vibrating could be done cyclically. By cyclically it is meant that component 4 is first heated to a target temperature range, specific to that component 4, then the heating may be paused and then immediately or quickly afterwards, such as less than a minute, the vibrating started, then the vibrating paused and then immediately or quickly afterwards, such as less than a minute, the heating started again etc, with the cycle being repeated until all the cemented carbide bodies 2 have been recovered. Alternatively, a combination of simultaneous and cyclic heating and vibrating could be used. The at least one carbide body 2 could be, be is not limited to, a mining insert, a cutting pick or a blade shape carbide unit, but is could be any other carbide body 2 attached to a component 4.

[0051] The component 4 is typically a mining or construction component and for example could be a top hammer drill bit or leg, a down the hole (DTH) drill bit or leg, a cone bit, a cutting pick, a raise boring shell, a rotary drill cone or leg, a horizontal direction drill (HDD) bit or leg, or reamer block leg but could be any other component 4 with at least one cemented carbide body 2 attached to it. The component 4 is typically made from steel and once all the cemented carbide bodies 2 have been removed, the steel from the component 4 could also be recycled.

[0052] The recovery method can be used for components 4 where the at least one cemented carbide insert 2 was pressed or brazed in position or held in any other way.

[0053] Typically, this recovery process would be used to recover at least one cemented carbide body 2 from used components 4, in this case they are commonly referred to as dull components 4. However, if required this method could also be used to remove at least one cemented carbide body 2 from an unused, new component 4.

[0054] The component 4 is vibrated in a vertical direction with respect to the axial axis 40, and the component is clamped in position so that the cemented carbide bodies 2 are facing downwards. For components 2 where the cemented carbide bodies 2 are positioned in multiple directions, for example rotary or HDD cones, it may be necessary to rotate the component 4 so that all the cemented carbides bodies 2 are at some point positioned downwards.

[0055] Typically, in step b) the component 4 is heated to a temperature of between 600-1000 C., more preferably to a temperature of between 700-900 C. The component 4 can continue to be heated until all of the cemented carbide bodies 2 have been recovered.

[0056] The relative position of the component 4 to the heating device 12 can be altered during the operation to heat different areas of the component 4 as necessary in order to optimise the rate of recovery of the at least one cemented carbide body 2 from the component 4. When induction heating is used the coil should be positioned as close to the component 4 as possible to achieve the most efficient heating so than minimal heat input is needed with the quickest extraction time, but not so close that contact is made and short circuited. The size and shape of the coil should be selected to maximise the efficiency of the heating.

[0057] A programmable rotating device could be used so that the rotation is pre-programmed to be conducted to suit the geometry of the specific component being processed.

[0058] Optionally, there is an additional step, between steps a) and b) wherein the component 4 is pre-heated. If a pre-heating step is included, this could be done either with the cemented carbide bodies 2 facing downwards or upwards, i.e. in the same position as in step b) or inverted. The pre-heating step us preferably done using induction heating, but could also be done using flame heating, or in a furnace. It is also possible for a combination of induction heating, flame heating and furnace heating to be used for the pre-heat if required. If pre-heating is used the component 4 would typically be heated to 600-1000 C., preferably 700-900 C.

[0059] The recovered at least one cemented carbide body 2 could then be collected and allowed to fall into the collection box (not shown), where they are left to cool. Once all the cemented carbide bodies 2 have been removed the component 4 is moved to a release position, from which the component 4 is dropped to be cooled.

[0060] Alternatively, the method for recovery of at least one cemented carbide body 2 from a component 4 comprises the steps of: firstly, clamping the component in a clamping device 6; secondly, heating the at least one cemented carbide body 2 using induction heating; and then thirdly, vibrating the component 4 to dislodge the at least one cemented carbide body 2 from the component 4.

[0061] It is also possible with any of the methods described herein to set the apparatus 8 up so that at least one cemented carbide body 4 can be removed from multiple components 4 as the same time. For example, a plurality of components 4 could be fixed, e.g. by welding, to a plate for processing all at one time.