EP3480419A1 - Auger drill assembly and method for forming an auger drill assembly - Google Patents

Abstract

The invention relates to a worm drill assembly and a method for forming a worm drill assembly having a first drill part and a second drill part, which are tubular or rod-shaped and in which at least one drill part is provided on its outside with a screw winding, the drill parts on at least one of them End portions having mutually mating connecting portions, wherein a first connecting portion is formed as a hulsenartiges nut part with Keilnutelementen and a second connecting portion as a mandrel-like Däterteil with Keilnutelementen, wherein the male part and female part are axially inserted into one another to form a releasable, non-rotatable connection. According to the invention, it is provided that on an inner wall of the nut member an annular inner groove is introduced, that on an outer wall of the male part an annular outer groove is introduced, that in a mated state of the female part and the male part, the inner groove and the outer groove face each other and form an annular space in that at least one insertion opening with a passage to the annular inner groove is formed on an outer wall of the nut part, and that a flexible steel cable is inserted over the insertion opening into the annular space and completely or largely fills it to form an axial securing.

Description

The invention relates to a worm drill assembly having a first drill part and a second drill part, which are tubular or rod-shaped and in which at least one drill part is provided on its outside with a screw winding, the drill parts have on at least one their end portions mating connecting portions, wherein a first connecting portion as a sleeve-like nut part with keyway elements and a second connecting portion are formed as a mandrel-like Däterteil with Keilnutelementen, wherein the male part and female part are axially inserted into one another to form a releasable, rotationally fixed connection, according to the preamble of claim 1.

The invention further relates to a method for forming such a screw auger arrangement according to the preamble of claim 12.

Such a worm boring arrangement is used in particular when forming so-called endless worm borers, which are used in particular for creating piles in the ground. The auger must have a length which corresponds at least to the depth of the hole to be created in the ground. The auger has on its outside one or more continuous screw turns, which serve to convey the soil material from the wellbore.

Depending on the necessary length, it is often necessary to assemble the auger assembly from several drill bits. The individual drill parts typically have a length of several meters. At their end sides, the drill parts are provided with connecting portions, with which they can be inserted and connected.

A generic auger assembly is for example from the DE 10 2006 022 613 B4 out. In a mated state, the auger parts can be secured axially by means of conical bolts, which have a screw thread, by screwing in the conical bolts from the outside radially inwards. Furthermore, it is also known from this document, rod-shaped, slightly curved clamping bracket tangentially inserted into a corresponding locking recess, so that the assembled drill parts are axially secured. Due to their bending, the clamps hold frictionally in the latch recess. The release of such clamping bracket from a bolt hole can be problematic.

From the DE 195 27 990 C1 a drill pipe arrangement is known in which a radially directed and spring-loaded snap pin is provided on a mandrel-like connecting portion of a drill string element. When inserting this mandrel-like male part into a sleeve-like female part of a further drill string element to be attached, the snap pin is first pushed back, in order then to lock radially outward into a locking bore. From this document continues the use of a U-shaped clamping bracket, which can also be inserted tangentially into locking recesses.

A rotary drill pipe with a connecting device with another snap pin is also from the DE 28 56 126 C2 out.

A modular auger is still from the EP 2 487 320 B1 known. At a drill bit, a central receiving shaft is provided, on which a plurality of spiral sheet metal sections can be plugged. The spiral sheet metal sections are screwed along the abutting edges of the spiral plates.

The invention has for its object to provide a Schneckenbohreranordnung and a method for forming such a Schneckenbohreranordnung, which allow a simple yet stable connection of several drill bits to form the auger assembly.

The object is achieved according to the invention on the one hand by a worm drill assembly with the features of claim 1 and on the other hand by a method having the features of claim 12. Preferred embodiments of the invention are indicated in the dependent claims.

The auger assembly according to the invention is characterized in that an annular inner groove is attached to an inner wall of the nut member, that on an outer wall of the male member an annular outer groove is introduced, that in a mated state of the female part and the male part, the inner groove and outer groove opposite each other and form an annular space in that at least one insertion opening with a passage to the annular inner groove is formed on an outer wall of the nut part, and that a flexible steel cable is inserted into the annular space via the insertion opening and completely or largely fills it to form an axial lock.

A basic idea of the invention is to provide corresponding connecting sections with a sleeve-shaped female part and a mandrel-like male part for connecting drill parts of a worm drill arrangement, wherein at least one drill part has an external worm winding. In this case, an annular inner groove and on an outer wall of the mandrel-like male part an annular outer groove is arranged such that they face each other in a mated state on an inner wall of the female part. In this mated state, a rotationally fixed connection is achieved in that corresponding wedge groove elements engage on the nut part and the male part for torque transmission in the circumferential direction.

For axial securing of the connection in the assembled state, an insertion opening with a passage to the annular inner groove is provided on the female part. About this insertion a flexible steel cable can be inserted into the common annular space, which is formed by the inner groove and the outer groove in the mated condition. Due to its flexibility, the steel cable can follow the bent annular space and be inserted into it so that the annular space is completely or to a large extent filled. The steel cable thus constitutes an axial locking element. The outer diameter of the steel cable and the inner diameter of the annular space form a clearance fit.

The common annulus and the steel cord are preferably circular in cross-section.

Accordingly, the inner groove and the outer groove each have a semicircular cross-section. Other cross sections, such as square, are possible in principle.

A steel cable as a locking element is very inexpensive and stable. It can be easily inserted into an annular space due to its flexibility, whereby a positive locking is achieved practically over the entire circumference of the tubular connecting portion. A steel cable is also very robust and not very susceptible to wear.

A preferred embodiment of the invention is that a plurality of outer grooves and a plurality of inner grooves are provided which form a plurality of annular spaces in the assembled state. It can be achieved as a multiple lock. Preferably, two, three or more annular spaces are arranged parallel to each other at a connecting portion. In principle, the annular spaces formed are closed in the circumferential direction. However, the annular spaces could also have a certain helical shape, so with a single steel cable so a multiple wrap and multiple locking could be achieved.

In principle, the grooves can be arranged at arbitrary locations of the connecting sections. From a wear point of view, it is particularly expedient that the inner grooves and the outer grooves lie in a direction of insertion behind the keyway elements at a connecting section. This is preferably true for the inner male part, while the arrangement on the outer female part is correspondingly reversed. The keyway elements are thus closer to the free end of the respective connecting portion. By means of the keyway elements, a first mechanical connection and guidance during mating can thus be achieved.

A further advantageous embodiment of the invention can be seen in that a sealing region is arranged on at least one connecting portion. Preferably, sealing areas are provided at the two opposite connecting portions, which correspond with each other, so that a seal in the region of the connection is achieved. This is particularly advantageous when the auger assembly overall tubular with an inner Cavity is, which is about to pass through drilling suspension, compressed air or concrete.

According to a development of the invention, it is particularly advantageous that the sealing region has at least one sealing ring. For this purpose, an annular groove for receiving a sealing ring, in particular an O-ring, may preferably be provided in one of the sealing areas. The corresponding surrounding sealing area can have a smooth sealing surface on which the sealing ring comes to bear sealingly.

A particularly expedient embodiment variant of the invention consists in that the keyway elements lie between the sealing region and the inner grooves or the outer grooves. The arrangement of the sealing region in a front region can prevent, in particular, a curable liquid from penetrating into the intermediate space between the connecting elements and, in particular, contaminating the keyway elements or the inner and outer grooves.

The steel cord may preferably be an elastically flexible wire of a unitary material or a braided rope having a plurality of steel cord fibers. Under steel rope is to be understood in particular a rope which is formed of a ferrous steel or a corresponding stable metal or a material with comparable strength and flexibility. It is particularly preferred that a stop element is attached to the flexible steel cable at a portion. By the stop element is achieved that the steel cable to release the connection again can be easily pulled out of the common annulus.

It is particularly advantageous in this case that the stop element can be received in the insertion opening. In this case, the insertion opening has a dimensioning, which allows the stop element is wholly or at least partially received in the insertion opening. Preferably, the stop member does not protrude from the insertion opening so that in a drilling operation it is exposed to little or no wear by passing the soil material past it. Additionally or alternatively, the insertion can be covered by a clamp or the like. At the same time, however, the stop element is dimensioned larger than the passage to the annular space, so that the steel cable only up to the stop element in the annulus can be introduced. This allows a safe gripping and loosening of the steel cable from the annulus.

A particularly good handling is achieved according to a further variant of the invention in that the insertion opening is formed as a slot which extends along a part of the annular space, and that the stop member has a length which is smaller than the length of the slot of the insertion opening.

For the simplest possible insertion of the steel cable into the annular space, it is advantageous for the flexible steel cable to have an insertion tip at a front end. The insertion tip can be formed directly on the steel cable or formed by applying a corresponding part with a conical shape.

A further preferred embodiment of the invention can be seen in that the stop element is arranged at a distance from a rear end of the flexible steel cable, wherein a free-standing latch portion of the steel cable is formed, which serves for inserting the steel cable into the annular space on both sides. In this case, the freestanding locking portion and the length of the stop element are designed such that they can be inserted into the insertion opening, in particular a slot, in a first insertion direction preferably completely. Subsequently, the steel cable can be moved within the annular space with the stop element in the opposite direction, wherein the free-standing latch portion is also received in the annular space formed. Thus, the stop element is secured on both sides by sections of the steel cable in the annulus, so that a good positional assurance is given.

The inventive method is characterized in that a first drill part and a second drill part are axially inserted into each other, which have at least one female part or a male part, that in the assembled state by an annular inner groove on an inner wall of the female part and by an annular outer groove on a Outside wall of the female part a common annular space is formed, that via an insertion opening on an outer wall of the female part via a passage a flexible steel cable is inserted, which the annular space completely or largely fills, with an axial securing between the first drill part and the second drill part is formed.

The method according to the invention is provided for forming a screw arrangement which has been described above. In this case, the advantages described above can be achieved.

Fig. 1

eine schematische Teilansicht einer erfindungsgemäßen Schneckenbohreranordnung beim Zusammenstecken;

Fig. 2

eine Teilquerschnittsansicht eines Mutterteils an einem Bohrerteil;

Fig. 3

eine weitere Querschnittsansicht des Mutterteils von Fig. 2 mit um 90° gedrehter Schnittrichtung;

Fig. 4

eine vergrößerte Detailansicht von Innennuten an dem Mutterteil gemäß Fig.3;

Fig. 5

eine Seitenansicht auf ein passendes Vaterteil eines Bohrerteils für die erfindungsgemäße Schneckenbohreranordnung;

Fig. 6

eine Querschnittsansicht des Vatersteils von Fig. 5;

Fig. 7

eine Teilansicht von Vaterteil und Mutterteil in einem zusammengesteckten Zustand;

Fig. 8

eine Querschnittsansicht gemäß dem Schnitt C-C von Fig. 7;

Fig. 9

eine Detailquerschnittsansicht zu gebildeten Ringräumen in einem zusammengesteckten Zustand;

Fig. 10

eine Draufsicht auf ein erfindungsgemäßes Stahlseil;

Fig. 11

eine Seitenansicht des Stahlseils von Fig. 10; und

Fig. 12

eine Draufsicht auf ein abgeändertes Stahlseil gemäß der Erfindung.

The invention will be further described by means of preferred embodiments, which are shown schematically in the drawings. In the drawings show:

Fig. 1

a schematic partial view of a screw auger assembly according to the invention during mating;

Fig. 2

a partial cross-sectional view of a nut member on a drill part;

Fig. 3

another cross-sectional view of the female part of Fig. 2 with cutting direction rotated by 90 °;

Fig. 4

an enlarged detail view of internal grooves on the female part according to Figure 3 ;

Fig. 5

a side view of a matching male part of a drill part for the auger assembly according to the invention;

Fig. 6

a cross-sectional view of the father part of Fig. 5 ;

Fig. 7

a partial view of the male part and female part in a mated state;

Fig. 8

a cross-sectional view according to the section CC of Fig. 7 ;

Fig. 9

a detail cross-sectional view of formed annular spaces in a mated state;

Fig. 10

a plan view of a steel rope according to the invention;

Fig. 11

a side view of the steel rope of Fig. 10 ; and

Fig. 12

a plan view of a modified steel cable according to the invention.

A worm boring assembly 10 according to the invention is shown schematically during the mating of a first drill part 12 and a second drill part 14 in FIG Fig. 1 shown. The first drill part 12 has at one end a first connecting portion 20 which is formed as a nut part 21 with a receiving space. In this nut member 21 is a pin-like male member 41 can be inserted, which is formed at a second connecting portion 40 at the adjacent second drill part 14. At the first drill part 12 and the second drill part 14 each have a screw turn 16 for conveying drilled soil material is arranged. In the Fig. 1 shown screw is right-handed, but can also be designed left-handed.

The auger assembly 10 according to the invention is used in particular for creating holes in the ground, for example for the manufacture of ground piles, for example for foundations. The auger assembly 10 may be constructed from a plurality of drill bits which are interconnected as described below. At the lower end of the auger assembly 10 is usually a soil-removing tool, while at the other upper end a connection to a rotary drilling drive and optionally a fluid port for supplying a fluid, such as drilling suspension or a hardenable mass, in the interior of the auger assembly 10 are arranged.

The following is related to the FIGS. 2 to 4 the construction of a nut member 21 for the auger assembly 10 according to the invention described. The first connecting portion 20 with the nut member 21 is in the FIGS. 2 to 4 each shown without the pipe body and the screw winding. The female part 21 is sleeve-shaped with an open end 22, into which the male part 41 can be inserted. To produce a rotationally fixed connection, first keyway elements 21 are in a central region of the receiving space of the nut part 21 24 trained. Between the first keyway elements 24 and the open end 22, two inner grooves 30 with a semicircular groove cross-section are incorporated on an inner wall 28. On an outer wall 36 of the nut member 21, two insertion openings 38 are formed as slots, as clearly in Fig. 3 is shown. The insertion openings 38 are connected via a passage in each case with one of the grooves 30. Through the insertion openings 38, a steel cable can be inserted to form an axial securing, as will be described in more detail below.

At the end of the first connecting portion 20 opposite the open end 22, a first fastening portion 34 is formed, to which the tubular base body for forming the first drill part 12 can be attached, in particular welded. Between the first mounting portion 34 and the first splines 24, a first sealing portion 26 is disposed with a cylindrical inner wall. This first sealing region 26 serves to receive a corresponding sealing region, which is formed on the associated male part 41, as will be described in more detail below. The first connecting portion 20 with the female part 21 may be made in one piece or as a multi-part welded part, as in the alternative embodiments according to the FIGS. 2 and 3 is shown.

In the FIGS. 5 and 6 a matching second connecting portion 40 is shown with a male part 41, which in the female part 21 according to the FIGS. 2 to 4 is pluggable.

The spike-like and tubular male part 41 has at its front end a second sealing region 46 with grooves 47 for receiving sealing rings. The second sealing portion 46 is formed so as to form a fluid-tight seal in the inserted state with the first sealing portion 26 on the nut member 21.

Following the second sealing region 46, second wedge groove elements 44 are formed on an outer side of the male part 41. These correspond to the first keyway elements 24 on the nut member 21 so that they are axially nestable to form a torque transmitting connecting portion, such as Fig. 7 shows.

In a subsequent outer wall 48 of the male part 41, two outer grooves 50 are introduced. In a mated state of the male part 41 and female part 21, the outer grooves 50 formed with a semicircular cross-section face the inner grooves 30 on the female part 21, so that a common annular space 60 having a round cross-section is formed. This is vivid in Fig. 9 shown.

At a rear end of the male part 41, a second fastening portion 54 is formed, which serves for attaching the further tubular body of the second drill part 14. Each drill bit 12, 14 may have a first connection portion 20 and a second connection portion 40 at opposite ends for a modular construction.

An interaction of the first and second Keilnutelemente 24, 44 is clearly in the FIGS. 7 and 8 shown. The first Keilnutelemente 24 on the female part 21 and the second Keilnutelemente 44 on the male part 41 are formed corresponding in their length and width, so that they are axially inserted into one another. The flanks of the keyway elements 24, 44 abut each other and can serve for torque transmission between the nut part 21 and the male part 41. In Fig. 7 In addition, the two insertion openings 38 are indicated schematically on the female part 21.

The FIGS. 1 to 9 show the subject invention on a reduced scale, while in the following FIGS. 10 to 12 a provided for the invention steel wire 70 is shown in a different, larger scale. The show FIGS. 10 and 11 a first cable 70 according to the invention with a cable main body 72. At one end of the cable main body 72 an insertion tip 74 is formed, which serves to insert the steel cable 70 via the insertion opening 38 in the female part 21 in the formed annular space 60. The flexible steel cable 70 preferably has a circular cross section whose outer diameter forms a clearance fit to the inner diameter of the annular space 60. The inserted steel cable 70 forms a form-fitting body, which axially secures the nested drill parts 12, 14 in their position.

At the other end, which is opposite to the insertion tip 74, a block-like stop element 76 is attached to the cable main body 72, preferably through Brazing or welding. The block-like stop element 76 has a dimensioning which makes it possible to insert the stop element 76 into the insertion opening 38 on the nut part 21, but further insertion into the annular space 60 is prevented.

An alternative embodiment of the steel cable 70 is in Fig. 12 shown. This steel cord 70 also has a cable base of a metallic flexible material and an insertion tip 74 and a block-like stop member 76 as in the embodiment of the FIGS. 10 and 11 on. In contrast to the first embodiment, the block-like stop element 76 is spaced from the rear end, so that a latch portion 78 is formed. The length of the locking portion 78 and the length of the stop element 76 are together smaller than the length of the insertion opening 38 on the female part 21. Thus, the steel cable 70 can first be inserted in an insertion direction with the insertion tip 74 into the annular space 60 until the stop element 76 at one end of the insertion opening 38 abuts the nut part 21. In this stop situation, the locking portion 78 is received in the insertion opening 38. Now, the cable 70 can be displaced in the opposite direction in the annular space 60, so that the locking portion 78 is inserted into the annular space 60. In this way, the steel cable 70 is accommodated with both end regions in the annular space 60, so that the steel cable 70 is particularly reliably received and locked in the annular space 60.

Claims (12)

Auger arrangement with
a first drill part (12) and a second drill part (14) which are tubular or rod-shaped and in which at least one drill part (12, 14) is provided on its outside with a screw turn (16),
the drill parts (12, 14) having connection sections (20, 40) which mate with each other at at least one of their end regions,
wherein a first connecting portion (20) as a sleeve-like nut part (21) with keyway elements (24) and a second connecting portion (40) as a mandrel-like dado part (41) are formed with keyway elements (44)
wherein the male part (41) and the female part (21) are axially inserted into one another for forming a releasable, rotationally fixed connection,
characterized by in that an annular inner groove (30) is made on an inner wall (28) of the nut part (21), that an annular outer groove (50) is introduced on an outer wall (48) of the male part (41), in that, in a mated condition of the female part (21) and the male part (41), the inner groove (30) and the outer groove (50) are opposite each other and form an annular space (60), - That on an outer wall (36) of the nut member (21) at least one insertion opening (38) is formed with a passage to the annular inner groove (30) and - That for forming an axial securing a flexible steel cable (70) via the insertion opening (38) is inserted into the annular space (60) and this completely or largely fills. Auger assembly according to claim 1,
characterized,
in that a plurality of outer grooves (50) and a plurality of inner grooves (30) are provided, which form a plurality of annular spaces (60) in the assembled state. Auger assembly according to claim 1 or 2,
characterized,
that at a connecting portion (20, 40), the inner grooves (30) and the outer grooves (50) in a plug behind the keyway elements (24, 44) lie. Auger assembly according to one of claims 1 to 3,
characterized,
that at least one connecting portion (20, 40) a sealing region (26, 46) is arranged. Auger assembly according to claim 4,
characterized,
that the sealing region (46) has at least one sealing ring. Auger assembly according to claim 4 or 5,
characterized,
in that the wedge-groove elements (24, 44) lie between the sealing region (26, 46) and the internal grooves (30) or the external grooves (50). Auger assembly according to one of claims 1 to 6,
characterized,
that on the flexible steel cable (70) at one end portion a stop member (76) is mounted. Auger assembly according to claim 7,
characterized,
that the stop element (76) is accommodated in the insertion opening (38). Auger assembly according to claim 7 or 8,
characterized,
that the insertion opening (38) is formed as a slot which extends along a part of the annular space (60), and
in that the stop element (76) has a length which is smaller than the length of the oblong hole of the insertion opening (38). Auger assembly according to one of claims 1 to 9,
characterized,
in that the flexible steel cable (70) has an insertion tip (74) at a front end. Auger assembly according to one of claims 7 to 10,
characterized,
in that the stop element (76) is arranged at a distance from a rear end of the flexible steel cable (70), wherein a freestanding locking section (78) of the steel cable (70) is formed, which is used to push the steel cable (70) into the annular space (60) on both sides. serves. A method of forming a worm boring assembly (10) according to any one of claims 1 to 11,
characterized,
in that a first drill part and a second drill part (14) are inserted axially into one another, which have at least one nut part (21) or a father part (41),
in that, in the mated state, a common annular space (60) is formed by an annular inner groove (30) on an inner wall (28) of the female part (21) and by an annular outer groove (50) on an outer wall (48) of the male part (41) .
inserted that an insertion opening (38) on an outer wall (36) of the nut member (21) via a passage into the annular space (60) is a flexible steel cable (70) which completely or substantially fills the annular space (60), wherein an axial securing between the first drill part (12) and the second drill part (14) is formed.

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