EP2815062B1 - Device for dry drilling using drilling debris suction - Google Patents

Description

The invention relates to a device for dry drilling with cuttings flushing and dust extraction for underground mining use with a drill with one or more drill cradles, or those for purging the cuttings and the dust through the gap between the drill pipe and the borehole wall arranged at the borehole mouth suction cup and a suction hose for transporting the dissolved material to the filter housing of the dust filter and the vacuum generator are assigned, wherein the input nozzle serving as a Bohrkleinseparierer baffle is arranged downstream and wherein the dust filter is formed both the dust and the cuttings from the volume flow niederschlagend.

In well-known Bohrwagen, ie devices for dry drilling with Bohrkleinabsaugung a drill is mounted on a carriage movable on a chassis. These mobile drilling rigs are used, for example, underground driving in the distance and work with air flushing to transport out of the wellbore deepest material out of this. Such Bohrwagen are equipped with wheels or usually with caterpillar tracks and can also produce the so-called large-bore holes, which in these known devices ( DE 39 09 058 A1 ) the respective borehole is covered by a suction cup and connected to the suction cup air hose is connected to a vacuum generator and wherein for the deposition of the coarse material, a baffle plate system and for the deposition of the fine material, a filter unit are provided. As a vacuum generator serve radial fans, which generate at least in principle the necessary negative pressure to flush cuttings and dust by means of the air through the gap between the drill pipe and borehole wall out. to Support is often forced compressed air through the boring bars in the wellbore. A disadvantage of these known devices is that it is difficult even with correspondingly large suction cups to capture the entire dust and the entire cuttings safely. Dust separation over the cyclone additionally used in the general state of the art causes problems, because this is closed on the discharge side for safety reasons via a kind of sleeve. So not always with the necessary security of the deduction of coarse material is possible. The as a vacuum generator in the DE 39 09 058 A1 used radial fans have a flat curve and can not comply with the required volume flow with increasing pressure drop. There are always disruptions, so that the drilling operation is affected. The baffle plate system is complex and works in addition to its task as a separator especially as a crusher of the incident on the sheet cuttings. The filters used are not described in detail. At the time, hose filters that are difficult to clean were common. Since the entire unit is arranged on the Bohrwagen, the mechanical equipment, ie the structure of the vacuum generator and also the filter unit contrary to the teaching of the GB 695010A at most only to provide a drill rig with the necessary suction. Because of these difficulties, water flushing is used whenever possible and only with air extraction where water is not available. Apart from the fact that z. B. drilling in salt are possible only with appropriate air extraction, the dry suction and dry processing safety and hygienic advantages.

From the US 4,284,422 A (from 1981), a vacuum cleaner is known in which, in a the actual filter upstream, a kind of cyclone performing component, the entrained by the dust water and snow is separated from the dust. In this way, adverse caking on the filter surfaces, here covered filter tubes are prevented. The illustrated vacuum generator is a Venturi tube or a Venturi jet pump. This type of pump has a known low efficiency and is characterized by a significantly larger size. In addition, the pipes pollute easily, so they just underground
can hardly be used. In the GB 695 010 A (from 1950) a deduster for dry drilling is described, wherein the dust extractor are associated with several drills with Staubabsaugegeräte. Therefore, a correspondingly large, underground barely usable deduster is required. Subject of the claims are control valves, an emergency exit for the dust supply hose and facilities to secure the pressure in the dust supply hose. At the originating from 1936 US 2 094 775 A Pre-separation of the coarser cuttings takes place before the actual deduster in a kind of tube separator. The coarser and finer cuttings are introduced from above into the tube, with the finer cuttings emerging through holes distributed around the tube, while the coarser cuttings are to fall to the bottom of the tube to be withdrawn. A clear separation is not possible due to the speed of both dust components entering the pipe. The deduster after the US 4 521 232 A (from 1985) has a similar structure, except that the dust is kept together for a very long time and is separated too inaccurately. Also, this prior art is not suitable to meet the special requirements of modern underground mining and tunneling. Especially with larger and longer boreholes, it is not possible to suck the cuttings and the dust safely out of the borehole and then to separate them evenly and safely from the conveying air.

The invention is based on the object to provide a cuttings and the dust almost independent of the amount safely deducted from the well dedusting device.

The object is achieved in that each Bohrlafette with Bohrklein- / Staubabsaugung a dust filter and a rotary piston blower or a vacuum pump, which serve as a volume flow stable vacuum generator is assigned, that the baffle has a rubber or plastic coating and that the dust filter as a surface filter With Compact elements that are used by the clean gas side into the filter housing are formed.

In a device designed in this way, it is first of all advantageous that it is possible to dispense with a separate cuttings pre-separator, because the entire material sucked out of the borehole is cleaned in one and the same element, namely the surface filter, so that this surface filter only leaves clean air, which easily enters the cuttings Atmosphere can be delivered. Another advantage is that regardless of the occurrence of cuttings and dust always the same negative pressure at the borehole and the deduster can be provided so that the necessary security is there to suck out cuttings and dust from the well and "dispose". The surface filter itself is equipped with stable compact elements that can be used individually in the filter housing, which has the advantage that these compact elements are largely insensitive to the incoming dry cuttings and the dust and that they are arranged in particular so that very large areas for dedusting are available so that a satisfactory extraction and dedusting process is always guaranteed, even if there is a large amount of cuttings and especially dust. This surface filter unit is a back-cleaning filter. The dusty air is fed through the suction hose to the surface filter. In the first step, the cuttings-dust mixture flows against the baffle, which separates the coarse-grained material from the dust-air mixture.

The elements associated with the surface filter are arranged and designed such that they also resist the coarser cuttings components or ensure that they are separated from the airflow. To protect these elements, it is provided that the baffle wall used at the inlet nozzle and as Bohrkleinseparierer is made of metal. Against this baffle, the incoming air / dust stream or cuttings flow is passed, so that the heavier parts suffer such a large reduction in speed that they fall down and then separated or usually be discharged together with the dust. The coarser components of the air stream to be cleaned are thus safely deposited for the actual filter elements harmless before, so that the elements reach much longer service life. Due to the rubber or plastic coating, the impact of the cuttings on the impact wall is such that the grains do not disintegrate and release dust, but as such, slip off the baffle and fall down. An additional burden on the subsequent filter is thus safely avoided. As a next step, the dust-air mixture flows through the fabric filter. In this case, the absorbed dust deposits on the tissue and forms a filter cake. The filtered air enters the interior of the surface filter through the fabric and leaves the filter housing via the clean air duct. The volume flow stable vacuum generator is a rotary piston blower or a vacuum pump. Such positive displacement blowers operate without internal compression and resemble gear and rotary vane pumps. In such a rotary blower, two symmetrical rotary pistons rotate uniformly against each other. The air mixture flows into the fan housing, which encloses the two pistons, and is forcibly conveyed to the delivery side in the delivery chambers, which are formed by rotary pistons and housing. At the moment in which a piston head past the edge of the Voreinlasskanals, the volume of air delivered is compressed by backflow from the discharge nozzle. The discharge pressure adjusts according to the resistance of the pipeline and the downstream equipment. This has the advantage that with a change in the resistance in the suction line up to a maximum value, the capacity remains constant. The big advantage of this rotary blower is that they work practically even with varying pressure loss.

After an expedient embodiment of the invention, it is provided that the vacuum generator, the surface filter and any energy producers are assigned to a common trailer to be connected to the drilling vehicle or directly as a compact component drilling jumbo. The arrangement on a separate trailer, for example, behind the Bohrwagen of this taken back and forth, has the advantage that even relatively large-sized elements can be used without any problems, because for the necessary footprint is available. In addition, all necessary for dust removal and extraction components can be accommodated in a group and even if they are assigned as a compact component drilling the car directly, so are permanently connected to this. The trailer can be equipped with wheels or with skids, so that he can easily carry out the necessary movements with the drilling carriage.

For large drilling rig the Bohrwagenführer sitting in a cab, where he can control according to the invention from there not only the drill or drill drive, but also the vacuum generator, which are inventively each separately remotely controlled. It is understood that at the same time as possible with the vacuum generators and any accessories of the surface filter can be controlled with.

Additional power generators are needed to regularly clean the surface filters used, the invention foreseeing this, that the one or more energy producers for the cleaning of the surface filters are designed as mobile compressors or a hydraulic drive comprising. As a rule, they can be supplied from the drilling vehicle so that separate supply facilities are not required. The cleaning process is carried out by an intermittent pressure shock, which takes place counter to the outflow direction. The dry dust cakes are released from the filter elements by the sudden expansion and / or vibration of the filter elements and fall into the underlying transport screw.

In order to protect the baffle made of metal, but in particular to keep the noise level low, the invention provides that the baffle wall in the region of the inlet nozzle has the rubber or plastic coating. The The noise level can be lowered significantly and at the same time the sheet metal can be protected so that, if necessary, only a recoating of the baffle wall becomes necessary if this coating is too worn or damaged. The maintenance work and the repair work can be substantially simplified or even reduced, whereby one can confine itself advantageously to the area of the sheet or the baffle wall, which is actually taken up by the impinging coarse grains.

Both in the installation as well as necessary maintenance work, it is of considerable advantage that the compact elements of the surface filter can be inserted from the clean gas side into the filter housing, wherein it is provided according to the invention that the filter housing has on the clean gas side a manually operable housing door. Of course, at standstill of the device or device so the housing door is opened by hand, either swung aside or taken out, so then the interior of the surface filter to feed easily with the compact elements or perform the necessary maintenance.

It has already been mentioned that both the cuttings as well as the finer dust are expediently discharged together from the filter housing, which is possible because the filter housing is equipped on the housing bottom with a pendulum flap discharge. As a result, the small cuttings mixture is discharged discontinuously but evenly into the discharge unit, so that it can then be discharged via this and finally disposed of. The pendulum flap discharge ensures that the necessary negative pressure in the filter housing itself remains virtually unaffected or largely unaffected so that the downstream vacuum generators can not suck in air via this pendulum flap outlet.

The wrong suction of the air through the pendulum flap discharge is mainly avoided by the fact that the pendulum flap discharge is formed transiently in a tube screw conveyor or chain scraper conveyor, wherein the tube is bent up and end provided with a rotary valve provided with discharge. The tube screw conveyor and also the chain scraper conveyor run in a closed tube, so that the inflow of external air can be excluded up to the rotary valve. About the rotary valve then the separated material is filled into a corresponding transport container to be disposed of further.

According to an expedient further embodiment, it is provided that the discharge of the pipe screw with a level indicator or monitoring equipped dust collection systems, preferably bags are assigned. Such bags have a large receiving volume and consist of plastic threads, which ensure with little elasticity that a lot of overburden or cuttings and dust can be filled. In addition, then with closed bags and high amounts of particulate matter containing materials can be safely transported to the overburden.

In systems or devices used in underground mining and tunneling, it is expedient that the elements of the surface filter as the European Plastics Test Directive are sufficiently flame retardant and / or antistatic steel body filter elements are formed. In order for such devices of the invention can also be used in hazardous areas, without a conversion is required.

Earlier it has been pointed out that it is advantageous to be able to dispense with a separate filtering the cuttings can. In the case of large amounts of cuttings, it is possible according to the invention to pre-arrange a compact filter outside the filter housing, suitable as Bohrkleinseparierer suitable cyclone, wherein the cyclone has a feed nozzle and a bypass pipe and wherein the suction hose with one end to the feed port on the cyclone and the other end can be placed on the inner channel of the drill rods and wherein the suction hose has a length of up to 50 m. This can be above all easily overcome problematic peak values. Depending on the size of the Bohrkleinanfalls the suction hose is placed on the bypass port or the supply nozzle. Over the long suction hose, the device according to the invention can be arranged at an optimum distance from the working face.

The invention is particularly characterized by the fact that a device for suction and filtering is created during dry drilling, which always provides a stable volume flow independent of the changing pressure loss, so that a uniform drilling is possible. The resulting cuttings and the dust are safely transported out of the well and then further processed in the device or air and dust are separated, so that the clean air can then escape from the device, which is not a burden on the environment. The fact that a cyclone is only used in extreme cases, an uncertainty factor is switched off, without the coarse dust content or better the Bohrkleinanteil the air in the surface filter is a problem. This is namely designed so that the actual elements or surface filter parts are protected from these coarser portions. Advantageously, all device parts or elements are assembled into a compact unit, which are assigned either to the Bohrwagen itself or a separate trailer, which follows the drill and has its own rolling elements or slides. Especially for the rough operation in mining or tunneling, but especially in the large-bore drilling this suction device which is assigned to each drill mount as a unit is no longer hindering the drilling work, so optimal for larger maintenance intervals
Drilling can be achieved.

Figur 1

eine vergrößerte Ansicht der die Niederschlagung des Bohrkleins und Staubes bewirkenden Teilvorrichtung,

Figur 2

eine Seitenansicht der gesamten Absaugvorrichtung,

Figur 3

eine Draufsicht auf diese Absaugvorrichtung und

Figuren 4-6

eine Absaugvorrichtung mit Sammelcontainer und Zyklon.

Further details and advantages of the subject invention will become apparent from the following description of the accompanying drawings in which a preferred embodiment with the necessary details and individual parts is shown. Show it:

FIG. 1

an enlarged view of the crushing of the cuttings and dust causing sub-device,

FIG. 2

a side view of the entire suction device,

FIG. 3

a plan view of this suction device and

Figures 4-6

a suction device with collecting container and cyclone.

In FIG. 1 is shown by the suction device 1 substantially the Bohrkleinseparierer 2 'and dust filter 2. The vacuum generator 3 can only partially be seen, and indeed, because it is a side view, essentially only the clean air inlet 35 and the clean air outlet 36 of this vacuum generator 3 can be seen here. The reference numeral 10 illustrates that here the vacuum generator 3 is shown in the training as a rotary blower 10. The Bohrkleinseparierer 2 'and dust filter 2 is a surface filter 4, in the filter housing 17 a plurality of elements 5, 6 are housed. This surface filter 4, 4 ', 4 "is as in FIGS. 2 and 3 shown with a power generator 7 and a plurality of power generators 7, 7 'associated with a trailer 8, which can be pulled here on the footwall or on the ground by drilling jog, not shown. Out FIG. 3 are then also the other rotary blower 11 and 12 can be seen.

The actual area filter 4 is here associated with an intermediate trailer 14, which is fixed on the trailer 8. It may also be rails 38, 39, such as FIG. 3 suggests.

The air-dust-Bohrkleingemisch is passed via the suction hose 16 and the inlet nozzle 15 into the interior of the filter housing 17. Is recognizable in FIG. 1 in that a baffle wall 18, which consists of sheet metal and which has a rubber or plastic coating 19 in the entrance area, is arranged opposite this inlet connection 15. In particular, the coarser constituents of the air-dust mixture will impact on this rubber or plastic coating 19 with appropriate speed and then fall down towards the housing bottom 25, while the air-particulate mixture between the elements 5, 6, here in the form of rigid body filter elements 22, 23 penetrates into the dust while the outside remains on the filter surfaces, while the cleaned gas or the Air in the direction of the clean gas side 20 of the filter housing 17 flows and is then discharged via the outlet port 24.

On the clean gas side 20 of the filter housing 17, a housing door 21 is attached, which can be opened via a door handle 37 so that then the rigid body filter elements 22, 23 can be easily disassembled or mounted, so that the installation is advantageously carried out always from the clean air side or clean gas side 20 ago can be. The coarser dust but also the fine dust and cuttings fall as described in the direction of the housing bottom 25, where this mixture then passes through the pendulum flap discharge 26 in the tube screw conveyor 27. This tube screw conveyor 27 has a tube screw 28 which rotates in the closed tube 29 and ensures that the dust mixture is conveyed in the direction of discharge 30. There, a rotary valve 31 ensures that the mixture, without air can be sucked into the bags arranged below 32, 33 falls. These bags 32, 33 rest on pallets 34 and are well transportable together with these pallets 34. However, they can also be transported alone, for which they can be equipped with appropriate loops.

Earlier it has already been said that the FIGS. 2 and 3 clarify that the clean gas leaving the filter housing 17 or the clean air via the outlet port 24 and a hose not shown here to the clean air inlet 35 of the rotary blower 10 or 11 and 12 is guided to be subjected there to the vacuum generating process. Despite possibly changing pressure losses, the volume flow remains stable, so that this type of vacuum generation is particularly suitable for the below-mentioned purpose underground. The suction power can be brought to at least 50% higher than the purging air, so that a complete dust detection is always ensured. Since the Abscheidefähigkeit the filter is very high, breathable air leaves the surface filter 4 and the vacuum generator. 3

As mentioned shows FIG. 2 a side view, in particular, the clean air inlets 35 and clean air outlets 36 are shown, and indeed all coming here for use rotary lobe blower 10, 11, 12. That it is three units also with respect to the surface filter 4, illustrates FIG. 3 In this case, these surface filters are provided with the reference symbols 4, 4 'and 4 ". As a rule, these individual surface filters 4, 4', 4" are fixed on the intermediate trailers 14, but these intermediate trailers 14 are also designed as running rails 38, 39 can be or can be used.

The Figures 4-6 show an embodiment in which to support the Bohrkleinseparierers 2 'and the dust filter 2 the filter housing 17 outside a cyclone 50 assigned and thus upstream of the elements 5, 6 in the filter housing 17. This cyclone 50 can be switched so that it separates a certain coarser grain class of cuttings, so that the subsequent baffle 18 is protected from these coarser pieces of cuttings. But it can also be adjusted so that it separates a certain amount of cuttings, so as to relieve the subsequent Bohrkleinseparierer 2 'in the filter housing 17. It is also possible to remove the cyclone 50 from the influx, for which the suction hose 16 is stripped from the feed nozzle 51 and placed on the bypass pipe 52. The dust-laden air is then led in bypassing the cyclone 50 directly into the filter housing 17.

To FIG. 1 the end 53 of the suction hose 16 is shown connected to one of the inlet ports 15, 51, 52. At the outlet port 24 at the other end of the filter housing 17 of the connecting hose 54 is connected, which in FIG. 4 is shown in dashed lines and filter housing 17 and vacuum generator 3 and plunger blower 10, 11, 12 interconnected.

Instead of a bag 32, 33, is at the FIGS. 4 and 5 arranged under the rotary valve 31, a dust container 55, which is equipped with a level indicator 57. The filter housing 17 has at the upper edge 58 via a plurality of suspension eyelets 56 so as to be able to transport the entire component easier.

Claims (10)

1. Device for dry drilling with cuttings flushing and dust extraction, for use in underground mining with a drill with one or more drill rigs to which a vacuum extractor located at the mouth of the borehole and a suction hose (16) for transporting the loosened material to the filter housing (17) of a dust filter (2) and to a vacuum generator (3) are assigned to flush out the cuttings and the dust through the gap between drill rod and borehole wall, whereby a baffle (18) serving as a cuttings separator (2') is assigned to the inlet nozzle (15) of the filter housing (17) and whereby the dust filter (2) is designed to deposit not only the dust but also the cuttings from the volume flow,
   characterised in that
   a dust filter (2) and a rotary piston blower (10, 11, 12) or a vacuum pump, which serve as a stable vacuum generator (3) with regard to the volume flow, are assigned to each drill rig with cuttings and dust extraction, the deflecting wall (18) has a rubber to plastic coating (19) in the area of the inlet nozzle and the dust filters (2) are designed as surface filters (4, 4', 4") with compact elements (5, 6) that are insertable into the filter housing (17) from the pure gas side (20).
2. Device in accordance with claim 1,
   characterised in that
   the vacuum generator (3), the surface filters (4) and any power generators (7) are allocated to a common trailer (8) to be connected to the drilling truck or directly to the drilling truck as a compact component.
3. Device in accordance with claim 2,
   characterised in that
   the vacuum generators (3) are each designed to be separately remotely controllable.
4. Device in accordance with claim 2,
   characterised in that
   the power generator or power generators (7) for cleaning the surface filters (4) are designed as mobile compressors or having a hydraulic drive.
5. Device in accordance with claim 1,
   characterised in that
   the filter housing (17) on the pure gas side (20) has a manually operable housing door (21).
6. Device in accordance with claim 1,
   characterised in that
   the filter housing (17) on the housing floor (25) is equipped with a pendulum flap discharge (26).
7. Device in accordance with claim 6,
   characterised in that
   the pendulum flap discharge (26) is designed passing into a tube screw conveyor (27), whereby the conveyor's tube (29) is bent upwards and designed having a discharge (30) at the end with a rotary valve (31).
8. Device in accordance with claim 7,
   characterised in that
   dust collection systems, preferably bags (32,33) fitted with a level indicator or monitor (57) are to be assigned to the discharge (30) of the tube screw conveyor (28).
9. Device in accordance with claim 1,
   characterised in that
   the compact elements (5, 6) of the surface filter (4) are designed as flame retardant and/or antistatically treated rigid body filter elements (22, 23) on conformity with European plastic test guidelines.
10. Device in accordance with claim 1,
    characterised in that
    with large amounts of cuttings a suitable cyclone (50) is to be assigned to the surface filter (4) outside the filter housing (17) as cutting separator (2'), whereby the cyclone (50) has a feeder nozzle (51) and a bypass nozzle (52) and whereby the suction hose (16) can be placed with one end (53) on the feeder nozzle (51) at the cyclone (50) and with the other end on the inner channel of the drill rods and whereby the suction hose (16) has a length of up to 50 m.

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