HK1066581B - Method and device for drilling a hole and for securing an anchorage in a bore hole - Google Patents

Description

Method and apparatus for drilling and securing an anchor within a drilled hole

Technical Field

The invention relates to a method for drilling a hole in soil or rock material, in particular percussion drilling or rotary percussion drilling, and for fixing an anchor in the hole, wherein a drill hole is produced by a drill bit mounted on a drill rod and simultaneously a sleeve surrounding the drill rod at a distance is inserted; and to a device for drilling, in particular percussive or rotary percussive drilling, in soil or rock material and for producing an anchor, wherein a drill bit mounted on a drill rod produces a borehole and a sleeve surrounding the drill rod at a distance from the drill bit is provided.

Background

With regard to the production of a hole or bore hole in a soil or rock material, after which an anchor or a liner is fixed in the bore hole, it is known, for example from WO 98/21439 and WO 98/58132, to insert a sleeve into the bore hole during the drilling process, for example by percussion drilling or rotary percussion drilling, after which, after the drilling has been completed, a portion of the drill bit is removed from the bore hole, if necessary together with the drill rod, while the sleeve is left in the bore hole for the subsequent formation of an anchor bolt in the bore hole by filling the bore hole with an age-hardened substance. According to the design corresponding to WO 98/58132, the drill rod can be formed with ribs and grooves on its outer circumference in order to achieve a correspondingly good anchoring effect in the event that the drill rod is left in the borehole and subsequently filled.

Alternatively, it is also known to remove the drilling tool together with the drill rod from the borehole after a borehole has been made. Thereafter, an anchor or anchoring device is subsequently inserted into the borehole, for example, according to EP-B0241451, US-A4490074, DE-AS 2105888, US-A4310266. EP-a 0875663 and other documents describe embodiments in which the tubular anchor to be inserted afterwards is held at a reduced diameter relative to the final state by a corresponding fixing element, after which, after it has been fully inserted into the borehole and the fixing device has been removed, the prestressed tube, which usually has a substantially longitudinally extending opening, is expanded and thus supported or pressed against the borehole wall to achieve the desired anchoring effect. In this known prior art, it is disadvantageous that, on the one hand, in a first method step a borehole must be produced, after which, after removal of the drilling tool together with the drill rod, in a further method step the anchoring device is inserted into the borehole, which may have a considerable length, and then subsequently supported on the borehole wall with expansion of the outer diameter by removal of the corresponding fixing device. It is obvious that not only are two separate work steps time consuming, but that it is also possible that the subsequent installation of such a long anchoring device is difficult. Furthermore, it is to be expected that the drilling device with the removal of the drill rod and the subsequent installation of the anchoring device can only be carried out in relatively strong soil or rock, wherein it must be ensured that no material falls into the drill hole, for example during the drilling process or after the removal of the drilling tool, before the final installation of the anchoring device, or that the drill hole is blocked and the anchoring device can no longer be installed.

Disclosure of Invention

The object of the invention is therefore to provide a method and a device of the type mentioned at the outset, in which, with a simplified construction, protection can be provided at least temporarily during the drilling process and an anchor is obtained directly on the inner wall of the drilled hole after the drilling has been completed.

To achieve this object, the method according to the invention is based on a method of the type mentioned at the outset, which is essentially characterized in that a sleeve provided with a longitudinal opening is at least partially inserted during the drilling process and is supported essentially on the drill hole. The provision of the longitudinal opening ensures that the sleeve is sufficiently elastic or pliable so as not to oppose the insertion of the sleeve, for example by means of tensile or impact stresses, even when at least partially bearing against the borehole wall. Furthermore, by means of the sleeve having the longitudinal opening it is ensured that: after the drilling has been completed, a corresponding anchor can reach the wall of the borehole directly by at least partial support, so that a time saving can be achieved for such an anchor design compared to known designs, wherein the drill rod is removed after the drilling has been completed and a separate anchor bolt can be inserted into the borehole. Furthermore, the method according to the invention can be applied independently of the soil material or rock material to be drilled through, since the casing is inserted into the borehole directly at the time of production or formation of the borehole, so that even in the case of very loose rock, in which case the problem of collapse may have to be taken into account at least after removal of the drilling tool and before insertion of the anchor, there is no need at all to worry about the difficulties as encountered when the anchor is to be set up afterwards, since the casing inserted during drilling always maintains the free passage cross section of the borehole even in the case of very loose rock. After the drilling has been completed or the drilling tool is at least partially removed together with the drill rod through the interior of the casing remaining in the drill hole, or the drill rod can also be left in the drill hole together with the drilling tool in order to increase the anchoring effect, so that not only the anchoring effect is generated by the support of the casing on the inner wall of the drill hole, but also the anchoring effect can be increased by the drilling tool and the drill rod remaining in the drill hole. When a sleeve having a longitudinal opening is introduced to bear at least partially against the borehole wall, it is also contemplated that: when the flushing fluid is supplied to the region of the drill bit and the produced material is discharged therefrom, a corresponding layer of liquid or viscous material also occurs in the region of the outer circumference of the casing, which has a lubricating or sliding effect during the installation of the casing. After completion of the drilling and thus interruption of the continued supply of flushing fluid, it is possible to anticipate: during the age hardening of the material in the region of the outer circumference of the sleeve, the friction between the outer circumference of the sleeve and the inner wall of the borehole can be increased accordingly, so that a correspondingly good anchoring effect of the sleeve against the inner wall of the borehole can be achieved.

In order to facilitate the anchoring effect of the sleeve, which already at least partially abuts against the inner wall of the borehole during installation, according to a preferred embodiment it is proposed that: after drilling and removal of the drill string is completed, an expandable member is placed inside the casing and expanded. The expandable elements thus inserted make it possible to securely fix the sleeve, if necessary, along a partial region on the borehole wall, so that the anchoring effect can be increased.

In a particularly simple manner, an expandable element can be fixed in the interior of the sleeve in such a way that it is expanded by means of impact stress, as it corresponds to another preferred embodiment of the method according to the invention. Such an expandable element not only provides a reliable support of the sleeve on the inner wall of the borehole, but also prevents a reduction of the inner cross section of the sleeve, for example due to compressive stresses of the surrounding material or tensile stresses in the longitudinal direction of the anchor bolt formed by the sleeve, because: due to the arrangement of the longitudinal opening, tensile stresses, in particular in the longitudinal direction of the sleeve constituting the anchor, may lead to a reduction of the anchoring cross section of the sleeve, and thus to a corresponding reduction of the anchoring effect.

Depending on the surrounding material and thus also on the nature of the casing, it is particularly advisable for the casing to be installed during the drilling process: the casing is inserted into the borehole by means of tensile and/or impact stresses via a connection to the drill bit. The sleeve according to the invention can thus be connected to the drill bit, for example, in a suitable manner and introduced into the borehole solely by means of tensile stress during the drilling process. However, in particular for sleeves with a larger material cross section and thus higher strength, which are used to provide a correspondingly resistant anchor, the sleeve can additionally or alternatively be inserted into the borehole simultaneously with the drilling process by means of the impact stress, so that no excessive forces have to be applied to the drill bit in order to insert the associated sleeve.

In order to facilitate the insertion of the casing during the drilling process, according to a further preferred embodiment: after the drilling is completed, at least one sleeve which is open in a substantially longitudinal direction and whose connection is defined by a predetermined breaking point is disconnected.

A particularly simple disengagement or separation of the predetermined breaking point is preferably implemented according to the invention in that the disengagement or separation of the predetermined breaking point is effected by slightly retracting at least the impulse socket and the sleeve mounted thereon and advancing the impulse socket. After the drilling has been completed, the predetermined breaking point can thus be separated or broken away with the expansion or spreading of the front end of the sleeve by slightly withdrawing at least the percussion shoe and the ring bit possibly mounted thereon and subsequently advancing the percussion shoe again, wherein the sleeve is simultaneously fixed or at least partially frictionally supported in the drilled hole by means of the expansion of the inner diameter of the sleeve by means of the longitudinal opening produced by the percussion shoe, for example by means of mutually cooperating bearing surfaces provided in the region of the front end of the sleeve, so that a smooth bearing of the outer diameter of the expanded sleeve against the wall of the completed drilled hole can essentially be achieved.

In order to further increase the anchoring effect, in particular in the case of loose rock or in the case of a co-operation with the need to fix an anchor plate on the end projecting from the borehole, according to a further preferred embodiment it is proposed that: the inside of the casing is filled with a time-hardening compound after the drilling is completed. The material that is cured may then flow into the surrounding material, in particular at the front and along the longitudinal opening of the expandable sleeve, thereby improving the anchoring of the sleeve. By filling with the age-hardening compound and subsequent fixing with the anchoring plate to be arranged on the outer end of the sleeve, it is also possible to achieve fixing of the soil material or rock material, which may be loose, laminated.

In order to achieve the object set forth at the outset, a device of the type set forth at the outset is also provided, which is primarily characterized in that the sleeve has a longitudinal opening which extends substantially in the longitudinal direction of the sleeve. By the provision of a sleeve which is formed with a longitudinal opening it is ensured that: the sleeve can be inserted into the borehole with a correspondingly low frictional resistance and at least partial support against the borehole wall during the drilling process, after which a corresponding anchoring effect can be achieved by the sleeve bearing directly at least partially against the borehole wall after the drilling process has been completed.

In order to facilitate the anchoring effect, according to a preferred embodiment, it is proposed that: after drilling and removal of the drill string is completed, an expandable member is inserted into the interior of the casing and expanded to bear against the interior wall of the casing. By means of such expandable elements, which are supported in an expandable manner on the inner wall of the sleeve, it is possible to reliably anchor the sleeve in the borehole, wherein such expandable elements prevent a reduction of the sleeve cross section, in particular caused by tensile stresses acting on the anchors formed by the sleeve, and thus reliably maintain the desired anchoring effect.

In order to fix the expandable element particularly advantageously inside the sleeve, according to a particularly preferred embodiment: the expandable element is formed by a sleeve which is expandable by means of impact stress by enclosing a particularly conical element, wherein in particular when a plurality of expandable elements are arranged inside the sleeve and for their suitable positioning, according to a further preferred embodiment it is proposed that: the sleeve is provided with a protrusion or bulge on its inner wall for positioning the expandable element.

In order to be able to be installed particularly easily, it is preferably proposed that: the sleeve has at least one predetermined breaking point along its longitudinal opening extending substantially in the longitudinal direction of the sleeve. Due to the provision of the at least one predetermined breaking point along the longitudinal opening of the sleeve according to the invention, the sleeve can be inserted into the borehole in a simple manner during the drilling process, and after the drilling has been completed, the at least one predetermined breaking point is detached or separated in order to support the sleeve against the inner wall of the borehole for anchoring.

After the drilling has been completed, at least one predetermined breaking point must be able to be broken away by applying a corresponding force. The predetermined breaking point must however also ensure sufficient strength of the longitudinal opening extending substantially along the entire length of the casing during drilling. For this purpose, according to a further preferred embodiment, it is proposed that: at least one predetermined breaking point along the longitudinal opening of the sleeve is formed by a welding point overlapping the longitudinal opening. The corresponding positioning and arrangement and possibly also the number of welding points as predetermined breaking points should take into account the different requirements regarding resistance during drilling as well as the separation or detachment of the predetermined breaking points after the drilling has been completed.

In order to successfully insert the casing during the drilling process, it is also proposed that: the sleeve is fixed at its end facing the drill bit to the percussion block of the drill bit, as it corresponds to another preferred embodiment of the device according to the invention. In addition to the insertion of the sleeve by means of tensile stress by fixing the sleeve to the drill bit or the percussion mechanism, provision can also be made for: an impact stress is exerted on the end of the casing projecting from the borehole, which is possible in particular for casings with a higher strength.

In order to achieve a corresponding anchoring effect of the expandable sleeve after completion of the borehole, according to a further preferred embodiment it is proposed: the sleeve is made of a prestressed material, in particular a metal.

In order to achieve anchoring or to increase the anchoring effect, in particular in the case of partially loose layers of rock material, it is furthermore preferably proposed according to the invention that: after completion of the drilling, an anchor plate is fixed to the casing at the end of the casing protruding from the soil material or rock material.

In order to remove the mined rock in a smooth manner, according to a further preferred embodiment it is proposed that: the casing has at least one through-opening in its region immediately adjacent the end of the drill bit for the purpose of conveying mined soil or rock material into the interior of the casing so that the mined material can also be discharged from the borehole in the free space defined between the drill rod and the casing, in particular the annular space.

Drawings

The invention is explained in more detail below with the aid of embodiments that are schematically shown in the drawings. Wherein:

FIG. 1 is a schematic side view, partly in section, of a first embodiment of the apparatus according to the invention for carrying out the process according to the invention;

FIG. 2 is an enlarged schematic cross-sectional view taken along line II-II of FIG. 1;

FIG. 3 is a view similar to FIG. 1 of a variant embodiment of the device according to the invention for carrying out the method according to the invention;

FIG. 4 is a view, again similar to FIG. 1, of a further variant embodiment of the device according to the invention for carrying out the method according to the invention;

FIG. 5 shows different stages in the process of carrying out the method of the invention using the device of the invention, wherein FIG. 5a shows, in a view similar to FIG. 1, the process of making a borehole by the method of the invention, FIG. 5b shows the removal of the drill string after the borehole has been completed, FIG. 5c shows the insertion of an expandable element into the interior of the casing after the borehole has been completed and the removal of the drill string, and FIG. 5d shows the process of expansion of the expandable element; and

fig. 6 is a schematic side view of another variant embodiment of the device according to the invention for carrying out the method according to the invention.

Detailed Description

In fig. 1, a drilling tool or a drill bit is designated as a whole by 1, which is connected to a drill rod 5 extending inside a casing 4 by means of an intermediate connection 2 and an impact socket schematically indicated by 3. A percussion drilling device or rotary percussion drilling device, not shown in greater detail, which is arranged outside the soil or rock material to be worked and whose surface is marked with 6, propels the drill bit 1 through the drill rod 5. The inner borehole profile formed by the drilling tool or bit 1 is schematically indicated at 7 in fig. 1.

As is evident from fig. 1, the sleeve 4 has a longitudinal opening 8 which extends substantially in the longitudinal direction, as is also evident from the view of fig. 2. In addition, it is evident from the illustration in fig. 2 that the sleeve 4 is made of a prestressed material, in particular a metal, wherein the material is larger at its outer circumference outside the borehole, indicated by a solid line, than at its outer circumference inside the borehole, indicated by a dashed thin line, the opening of which is marked 8'. The casing 4 is thus inserted into the borehole under prestress, so that it is ensured that the casing 4 bears at least partially against the borehole inner wall 7, in order thus to provide at least temporary protection already during the drilling process.

It is also apparent from fig. 2 that the drill rod 5 is provided with a central channel 9 by means of which flushing fluid can be fed into the region of the drill bit 1, so that the produced material is at least partially discharged between the casing 4 and the borehole inner wall 7 in the region of the outer circumference of the casing 4, wherein a lubricating or sliding effect is obtained at the interface between the casing outer circumference and the borehole inner wall 7 as a result of the fed flushing fluid. This lubricating or sliding effect correspondingly reduces the frictional resistance between the outer circumference of the sleeve 4 and the borehole inner wall 7, while after the completion of the introduction of the borehole 7 and thus of the flushing agent into the region of the drill bit 1, a frictional connection can be obtained between the sleeve 4 and the borehole inner wall 7 by means of age hardening.

In the embodiment shown in fig. 1, the insertion of the sleeve 4 is effected by means of a tensile stress exerted on the sleeve 4 by the percussion socket 3, the sleeve 4 having a conically tapering profile in its region 4' directly adjacent to the drill bit 1.

Fig. 1 shows a joint sleeve 10, which can hold a drive device, not shown in more detail, for percussion drilling or rotary percussion drilling.

In the variant embodiment shown in fig. 3, the outer sleeve 4 is subjected to impact stress in addition to the tensile stress applied by the impact socket 3 in the region of the anchor head 6 by the connecting sleeve 10, so that the sleeve 4 is inserted into the interior of the borehole, which is marked again with 7, both under tensile stress and also under impact stress.

The sleeve 4 has a longitudinal opening 8 and is tapered or formed with a reduced cross section in a partial region of its outer circumference, the tapered partial region being designated 11 in fig. 3. The sleeve 4 can therefore be supported only partially, in particular during the installation process, which is advantageous for achieving a smooth drilling process, for example in the case of a high frictional resistance which can be expected between the outer circumference of the sleeve 4 and the borehole inner wall 7.

In the further variant embodiment according to fig. 4, it is evident that the sleeve 4 is inserted into the interior of the borehole 7 only by the impact stress of the splicing sleeve 10 acting on the anchor head 6, without a pulling through the connection of the sleeve 4 to the drill bit 1 being achieved in this embodiment. The sleeve 4 can be inserted by means of impact stress in this way, in particular in the case of a correspondingly solid sleeve or a sleeve 4 with a high strength.

In the individual method steps shown in fig. 5, fig. 5a shows the formation or production of a borehole 7, in which the casing 4 is inserted, for example, in a manner similar to the embodiment of fig. 4, by means of the impact stress acting on the anchor head 6, without providing a connection between the casing 4 and the drill bit 1.

In fig. 5 an anchor plate 13 is shown at the end protruding from the soil material or rock material, respectively.

After completion of the borehole 7, the drill rod 5 is removed from the borehole 7 as shown in fig. 5b by the arrow 14, while the drill bit 1 remains in the borehole 7.

After removal of the drill rod, an expandable element, generally designated 15, is inserted into the interior of the casing 4 according to arrow 16. The expandable element 15 comprises a sleeve 17 which is conically tapered and at least partially has a longitudinal opening 18, wherein a conical element 19 can be inserted into the interior of the sleeve 17.

After the expandable two-part element 15 has been fitted or inserted into the interior of the sleeve 4, for example in the region of the stop or ledge 20 in order to position the expandable element, an impact stress is applied to the conical element 19 by the joint sleeve 10, so that the two-part expandable element 15 is positioned in the desired position inside the sleeve and is fixed to the inner wall of the sleeve 4.

This incorporated expandable element 15 ensures that no cross-sectional reduction of the sleeve 4 occurs, which may be caused, for example, by compressive stresses of the surrounding material or when tensile stresses are applied in the direction of movement of the anchor in the pull-out or detachment direction, so that the desired anchoring effect is reliably maintained. When a tensile stress acts on the anchor bolt formed by the sleeve 4, the sleeve 4 can, for the case where no expandable elements 15 are provided, reduce its cross section due to the longitudinal openings 8, which reduces the anchoring effect.

Instead of providing the positioning projections 20, it is also possible to have the expandable elements 15 bear directly on the drill bit 1 remaining in the borehole 7, and is shown in fig. 5 d. Furthermore, it can be provided that a plurality of expandable elements 15 are inserted into the interior of the sleeve 4 in order to be correspondingly supported in different positions with respect to the anchoring effect of the sleeve 4. Such a plurality of expandable elements 15 may be provided by a corresponding structural design, in particular by a conical sleeve 17 and cooperation with corresponding positioning projections 20.

Alternatively or in addition to the inserted expandable elements 15, provision can be made for the interior of the casing 4 to be filled with the age-hardening compound after the drilling 7 has been completed and, if necessary, the drill rod 5 removed.

In fig. 6, a further variant embodiment is denoted by 1 a drilling tool or a drill bit, which is connected via an intermediate connecting piece 2 and a percussion socket, schematically indicated by 3, to a drill rod 5 extending inside a casing 4, wherein a percussion drilling device or a rotary percussion drilling device, not shown in greater detail, which is arranged outside the soil or rock material to be worked and whose surface is denoted by 6, propels the drill bit 1 via the drill rod 5. The inner borehole contour formed by the drilling tool or bit 1 is again marked with 7 in fig. 6.

As shown in fig. 6, the sleeve 4 has a longitudinal opening 8 extending substantially in the longitudinal direction, wherein at least one predetermined breaking point 29 is provided along the longitudinal extent of the longitudinal opening 8, which predetermined breaking point is formed, for example, by a welding point 29. In which the sleeve 4 is fixed to the percussion shoe 3 via an intermediate element or is moved by the percussion shoe 3 during drilling, so that the sleeve 4, which forms the longitudinal opening 8 during drilling, is inserted directly into the borehole 7.

In order to remove the material produced by the drill head 1, a through-opening 31 is provided in the front of the casing 4, wherein the through-opening 31 is formed by an enlarged clear passage section forming the longitudinal opening 8. Material produced by the drilling tool 1 through the through-hole 31 enters the free space or annular space defined between the casing 4 and the drill rod 5 and is discharged at the end remote from the drill bit 1. If necessary, a second through-opening can be provided in the sleeve 4 in the region of a diametrically opposite part of its circumference, for example symmetrically to the through-opening 31.

After the drilling has been completed, the prestressed casing 4 is expanded by the detachment or separation of the welding points which determine the predetermined breaking point, whereby the desired anchoring effect can be achieved.

After the drilling has been completed, the sleeve 4 and at least the percussion shoe 3 and the part of the drill bit mounted thereon, for example the ring bit in the case of a central bore hole and a radially surrounding ring bit, are slightly withdrawn counter to the direction 26 of drilling or advancing, after which the percussion shoe 3 is again advanced in the direction 26 of the drilling process through the drill rod 5 after such withdrawal, whereby the predetermined breaking point 29 is broken off.

Claims (20)

1. Method for drilling holes in soil or rock material, wherein a drill hole (7) is produced by means of a drill bit (1) mounted on a drill rod (5) and simultaneously a sleeve (4) is inserted at a distance around the drill rod (5), characterized in that the sleeve (4) formed with a longitudinal opening (8) is inserted at least partially during the drilling process and is supported on the drill hole (7).

2. A method according to claim 1, characterized in that after completion of the drilling (7) and removal of the drill rod (5), an expandable element (15, 17, 19) is introduced into the interior of the casing (4) and expanded.

3. Method according to claim 2, characterized in that the expandable elements (15, 17, 19) are expanded by means of impact stress.

4. A method according to claim 1, 2 or 3, characterized in that the casing (4) is loaded into the borehole (7) by means of tensile and/or impact stress via a connection with the drill bit (1).

5. Method according to one of claims 1 to 3, characterized in that after the drilling (7) has been completed, at least one sleeve (4) which is open in the longitudinal direction is disconnected, the connection being defined by a predetermined breaking point (29).

6. Method according to claim 5, characterized in that the disengagement or separation of the predetermined breaking point (29) is effected by slightly withdrawing at least the impulse socket (3) and the sleeve (4) mounted thereon and pushing in the impulse socket (3).

7. A method according to claim 1, characterized in that after completion of the borehole (7), the interior of the casing (4) is filled with a time-hardening substance.

8. A method according to any one of claims 1 to 3, wherein the method is used for percussive drilling or rotary percussive drilling and for securing an anchor in a hole.

9. Device for drilling a hole in soil or rock material, wherein a drill bit (1) mounted on a drill rod (5) produces a drill hole (7) and wherein a casing (4) is provided which surrounds the drill rod (5) and which adjoins the drill bit (1) at a distance therefrom, characterized in that the casing (4) has a longitudinal opening (8) which extends in the longitudinal direction of the casing (4).

10. Device according to claim 9, characterized in that an expandable element (15, 17, 19) is insertable into the interior of the casing (4) and expandable to bear against the inner wall of the casing (4) after completion of the drilling (7) and removal of the drill rod (5).

11. A device according to claim 10, characterised in that the expandable element (15) is formed by a sleeve (17) which is expandable by impact stress by incorporating a conical element (19).

12. A device according to claim 10 or 11, characterised in that the sleeve (4) is provided with a protrusion or bulge (20) in its inner wall for positioning the expandable elements (15, 17, 19).

13. Device according to one of claims 9 to 11, characterized in that the sleeve (4) has at least one predetermined breaking point (29) along its longitudinal opening (8) extending in the longitudinal direction of the sleeve (4).

14. Device according to claim 13, characterized in that the at least one predetermined breaking point (29) is formed by a weld along the longitudinal opening (8) of the sleeve (4) overlapping the longitudinal opening (8).

15. Device according to one of claims 9 to 11, characterized in that the sleeve (4) is fixed to the percussion seat (3) of a drill bit (1) at the end facing the drill bit (1).

16. Device according to one of claims 9 to 11, characterized in that the sleeve (4) consists of a prestressed material.

17. Device according to one of claims 9 to 11, characterized in that the sleeve (4) consists of metal.

18. Device according to one of claims 9 to 11, characterized in that at least after completion of the drilling (7) an anchor plate (13) is fastened to the casing (4) at the end of the casing protruding from the soil material or rock material.

19. Device according to one of claims 9 to 11, characterized in that the casing (4) has at least one through-opening in its region immediately adjacent to the end of the drill bit (1) for feeding mined soil or rock material into the interior of the casing (4).

20. Device according to one of claims 9 to 11, characterized in that it is used for percussion drilling or rotary percussion drilling (7) and for producing an anchor.