CA3205101A1

CA3205101A1 - Steel wire mesh made of steel wires having hexagonal loops, production device, and production method

Info

Publication number: CA3205101A1
Application number: CA3205101A
Authority: CA
Inventors: Mario Brunn
Original assignee: Individual
Current assignee: Geobrugg AG
Priority date: 2021-01-14
Filing date: 2022-01-11
Publication date: 2022-07-21
Also published as: DE102021100678A1; PL4171847T3; EP4171847B1; CN116783016B; RS65404B1; EP4171847A1; WO2022152697A1; CN116783016A; CL2023001994A1; EP4171847C0; HRP20240332T1; MX2023008271A; US20240058858A1; AU2022207151A1; JP2024505424A; KR20230121886A; AU2022207151B2

Abstract

The invention is based on a steel wire netting (54a-d), in particular a hexagonal netting, made of steel wires (10a-d, 12a-d, 14a-d) with hexagonal meshes (16a-d), in particular for civil engineering purposes, preferably for an application in the field of protection from natural hazards, wherein the steel wires (10a-d, 12a-d, 14a-d) are alternatingly twisted with neighboring steel wires (10a-d, 12a-d, 14a-d) and wherein the steel wires (10a-d, 12a-d, 14a-d) are formed from a high-tensile steel or at least have a wire core made of a high-tensile steel. It is proposed that an, in particular average, ratio calculated from an, in particular average, mesh width (18a-d) of the hexagonal meshes (16a-d) and an, in particular average, mesh height (20a-d) of the hexagonal meshes (16a-d), measured perpendicularly to the mesh width (16a-d), amounts to at least 0.75, preferably to at least 0.8.

Description

Steel wire mesh made of steel wires having hexagonal loops, production device, and production method Prior art The invention concerns a steel wire netting according to the preamble of claim 1, a production device according to the preamble of claim 13 and a production method according to claim 17.
In the Polish patent document having the patent number PL 235814 B1 a hexagonal netting is described which is made of a high-tensile steel with a tensile strength between 1,500 N/mm2 and 1,900 N/mm2. However, the hexagonal netting described here has a special, in particular elongate, mesh shape, in which a ratio of mesh width and mesh height is compellingly always smaller than 0.75.
According to the aforementioned patent document, this mesh geometry substantially differs from customary mesh geometries of hexagonal nettings made of non-high-tensile steel wires, which are typically 60 mm x 80 mm (ratio 0.75), 80 mm x 100 mm (ratio 0.8) or 100 mm x 120 mm (ratio 0.83). These mesh dimensions are, however, clearly defined in a European standard for "steel wire nettings having hexagonal meshes for civil engineering purposes" (EN 10223-3:2013). Meshes having mesh width / mesh height ratios of less than 0.75, i.
e. the mesh width / mesh height ratios described in patent document PL 235814 B1, thus do not comply with the requirements of the European standard. The hexagonal mesh depicted in patent document PL 235814 B1 even has a mesh width / mesh height ratio that is merely 0.62. Only if the mesh width / mesh height ratio is 0.75 or more, the hexagonal nettings are also standard-compliant and are thus usable for civil engineering purposes in a regular fashion. In contrast thereto, in the ninth

- 2 -paragraph of patent document PL 235814 B1 it was clearly described that, in the opinion of the patent owner, it was currently not possible to make standard-size hexagonal nettings from high-tensile steel wires, and therefore a different (smaller) mesh width / mesh height ratio was necessarily required if high-tensile steel is used. Actually, on the market the demand for high-tensile hexagonal nettings was and is of such dimensions that the patent owner of patent document PL 235814 B1 offers and distributes the non-standard-compliant hexagonal nettings described in said patent document in spite of that. The market has for a long time shown a huge need for high-tensile hexagonal nettings which at the same time fulfill the requirements according to the standard EN 10223-3:2013 with regard to mesh shape and mesh dimensions, in particular with regard to the mesh width / mesh height ratio. Despite quite a number of efforts, such hexagonal nettings are not known to the market at the time of filing the present document.
The objective of the invention is in particular to provide a generic steel wire netting made of high-tensile steel wires and having an improved mesh geometry, in particular improved mesh width / mesh height ratios. The objective is achieved according to the invention by the features of patent claims 1, 13 and 17 while advantageous implementations and further developments of the invention may be gathered from the subclaims.
Advantages of the invention The invention is based on a steel wire netting, in particular a hexagonal netting, which is made of steel wires with hexagonal meshes, in particular for civil engineering purposes, preferably for an application in the field of protection from natural hazards, wherein the steel wires are alternatingly twisted with neighboring steel wires, preferably in a regular manner, and wherein the steel wires are formed of a high-tensile steel or at least have a wire core made of a high-tensile steel (e. g. high-tensile steel wires which are provided with an overlay or with a coating).

- 3 -It is proposed that an - in particular average - ratio calculated from an, in particular average, mesh width of the hexagonal meshes and from an, in particular average, mesh height of the hexagonal meshes measured perpendicularly to the mesh width, amounts to at least 0.75, preferably to at least 0.8. This advantageously allows providing a steel wire netting made of high-tensile steel wires with a particularly advantageous mesh geometry, in particular a mesh geometry that is already widely in use and well proven in the non-high-tensile field.
Advantageously, it is in this way possible to hold on to known and proven retaining properties of hexagonal nettings, which for example depend on rock sizes, while a strength, i.e. for example a tear resistance or rupture resistance, of the hexagonal netting may be increased considerably. Advantageously, as a result already existing planning and designs (e. g. of slope protection gabions, of coast protection gabions, of gully nets, of stone rolls, etc.), which up to now have used non-high-tensile hexagonal nettings with standard-compliant mesh sizes, can be improved and/or reinforced in a simple, uncomplicated manner (avoiding red tape), for example as the non-high-tensile hexagonal netting may be replaced, directly and without major changes, by a high-tensile hexagonal mesh netting having the same mesh geometry. It is for example advantageously possible that, with the slope protection gabions, the coast protection gabions, the gully nets and/or the stone rolls an identical filling material may be used, which in particular has an identical grain size of the filling material. This advantageously allows reducing cost as well as work input. In particular, the steel wire netting according to the invention cannot be produced either with known customary machines nor with the production device described in patent document PL 235814 81. Further modifications and/or method steps, which are explained in the present document, are hence indispensably required for the production of the steel wire netting according to the invention.
In particular, the hexagonal meshes have shapes of at least substantially symmetrical hexagons. In particular, the hexagonal meshes in each case have a slightly elongated honeycomb shape. In particular, the hexagonal meshes form a

- 4 -gap-free tessellation in a netting plane of the steel wire netting. By "civil engineering purposes" are in particular purposes to be understood which comprise planning, execution performance and/or modification carried out on a construction.
Examples for applications in a protection against natural hazards are the aforementioned gabions, like slope protection gabions, stone rolls, coast protection gabions or gully nets, but also cross-terrain spans, catchment fences, and the like.
In particular, an average value of a parameter, like for example an average mesh width / mesh height ratio, an average mesh width, an average mesh height, an average length of a twisted region of the steel wire netting that delimits a hexagonal mesh, an average length of a twisting, an average entry curvature of the steel wire in a transition from an at least substantially straight section of the steel wire that delimits a hexagonal mesh to a twisted region of the steel wire that delimits the hexagonal mesh, an average exit curvature of the steel wire in a transition from the twisted region of the steel wire that delimits the hexagonal mesh to an at least substantially straight further section of the steel wire that delimits the hexagonal mesh, and/or an average aperture angle of the hexagonal mesh, is created from an average value of several, in particular at least three, preferably at least five, preferentially at least seven and particularly preferably at least ten, meshes of the steel wire netting which have the parameter, wherein the meshes used for creating the average value are preferably not directly adjacent to each other.
A "mesh width" is in particular to mean a distance between two twisted regions of the steel wire netting which delimit a hexagonal mesh, which extend at least substantially parallel to each other and which are situated on opposite-situated sides of the hexagonal mesh. A "mesh height" is in particular to mean a distance between two corners of a hexagonal mesh of the steel wire netting, which are situated opposite each other in a direction parallel to a main extension direction of the twisted region. In particular, a twisting of the two steel wires delimiting the hexagonal mesh starts and/or ends at the corners of the hexagonal mesh between

- 5 -which the mesh height is measured. In particular, the mesh width of the hexagonal meshes of the steel wire netting is smaller than the mesh height of the hexagonal meshes of the steel wire netting. By a "main extension direction" of an object is herein in particular a direction to be understood which runs parallel to a longest edge of a smallest geometrical rectangular cuboid just still completely enclosing the object.
It is further proposed that the high-tensile steel of the steel wires has a tensile strength of at least 1,560 N/mm2, preferably of at least 1,700 N/mm2 and preferentially of at least1,950 N/mm2. This advantageously allows attaining especially high stability of the steel wire netting and/or of constructions made from/with the steel wire netting. Advantageously, in this way for example an especially favorable protection against natural hazards is achievable.
If, for example, the high-tensile steel of the steel wires at the same time has a tensile strength of maximally 2,150 N/mm2, it is advantageously possible to keep a brittleness of the steel wires of the steel wire netting, which increases with an increase in tensile strength, at a low level. Experiments have shown that - in particular when using steel wires which have tensile strengths in a narrow, specially selected range of tensile strengths between 1,700 N/mm2 and 2,150 N/mm2, preferably between 1,950 N/mm2 and 2,150 N/mm2- it is advantageously possible to create a particularly favorable balance between particularly high stability and at the same time limited brittleness. Such balance is especially advantageous, in particular for a utilization of the steel wire netting for the production of any kind of gabions. For example, this enables particularly high filling capacity, and thus particularly large and stable construction, of the gabions, which is at the same time particularly rupture-resistant in the case of an event, for example a rockfall, in which rocks fall on the gabions.
Furthermore, it is proposed that a length, in particular an average length, of a twisted region delimiting a hexagonal mesh is at least 30 %, preferably at least % and preferentially at least 40 % of the, in particular average, mesh height.

- 6 -This advantageously allows attaining particularly high stability of the steel wire netting. Advantageously, in this way a winding curvature in the twisted region of the hexagonal mesh can be kept in a (moderate) range in which a rupture risk of the high-tensile steel wire used is comparably low.
It is moreover proposed that a length, in particular an average length, of a twisted region delimiting a hexagonal mesh is at least 50 %, preferably at least 55 %
and preferentially at least 60 % of the, in particular average, mesh width. This advantageously allows attaining particularly high stability of the steel wire netting.
It is also proposed that that a length, in particular an average length, of a twisting within a twisted region delimiting a hexagonal mesh is less than 1.1 cm, preferably less than 1 cm, preferably with a diameter of the steel wires between 2 mm and 4 mm. This advantageously allows keeping a mesh height in a desired range without requiring too large entry curvatures and/or exit curvatures in a transition into/from the twisted region from/into the non-twisted region delimiting the hexagonal mesh. Advantageously, in this way and in particular together with the aforementioned minimum length of the twisted region, an especially favorable balance is achievable of a material-friendly winding curvature and material-friendly entry and exit curvatures, thus in particular enabling a high level of overall stability and/or overall rupture-resistance of the steel wire netting.
Preferably, in a transition from an at least substantially straight section of the steel wire that delimits a hexagonal mesh, to a twisted section of the steel wire that delimits a hexagonal mesh, an, in particular average, entry curvature of the steel wire is at least substantially equal to the, in particular average, exit curvature of the steel wire in a transition from the twisted region of the steel wire that delimits the hexagonal mesh to an at least substantially straight further section of the steel wire that delimits the hexagonal mesh. This advantageously allows achieving an especially high degree of symmetry of the hexagonal meshes, thus advantageously enabling particularly even load-bearing capacity in at least two pulling directions of the steel wire netting which are situated opposite each other

- 7 -along the mesh height, preferably in all directions of the wire netting. It is in this way advantageously possible to prevent installation mistakes, for example an installation of a non-symmetrical steel wire netting inverted by 180 .
"Substantially equal" is to mean, in this context, with a deviation of the curvature radii of the curvatures that is in particular less than 20 %, preferably less than 15 %, advantageously less than 10 %, preferentially less than 5 % and especially preferentially less than 2.5 %. Preferably, in the transition from the at least substantially straight section of the steel wire that delimits the hexagonal mesh to the twisted region of the steel wire that delimits the hexagonal mesh, the steel wires bend to an at least substantially equal extent as in the transition from the twisted region of the steel wire that delimits the hexagonal mesh to the at least substantially straight further section of the steel wire that delimits the hexagonal mesh. "To bend to an at least substantially equal extent" is in particular to mean, in this context, that bends which are visible in a view from above onto the steel wire netting have bending angles in the transitions which differ by less than 20 %, preferably by less than 15 %, advantageously by less than 10 %, preferentially by less than 5 % and particularly preferably by less than 2.5 %.
In addition, it is proposed that a twisted region delimiting a hexagonal mesh comprises more than three consecutive twistings, which in particular have the same direction. This in particular allows attaining high stability of the steel wire netting. Advantageously it is moreover possible to reduce a probability of complete untwisting of a twisted region in the case of a wire rupture in the twisted region.
Preferably the twisted region delimiting the hexagonal mesh comprises at least five or at least seven consecutive twistings, which preferably have the same direction. By a "twisting" is in particular an 180 -wrapping of one the steel wires by the neighboring steel wire. Preferably a firm screw-like winding of two wires around each other, with a wrapping of both wires by 180 , is to be understood as a twisting. In the case of three consecutive twistings, each steel wire is thus wound around by the respectively other steel wire by 540 (five-fold: 900 , seven-fold:
1260 ).

- 8 -If preferably at least one, in particular average, aperture angle of the hexagonal mesh, spanning the hexagonal mesh in a longitudinal direction, is at least 700 , preferably at least 80 and preferentially at least 90 , advantageously a high degree of stability is enabled while maintaining the advantageous mesh width /
mesh height ratio of 0.75. Advantageously, the advantageous mesh width / mesh height ratio of 0.75 or more is achievable with twisted regions which at the same time have sufficient length, thus avoiding wire rupture. The aperture angle spanning the hexagonal mesh in the longitudinal direction is in particular the angle spanned by the (non-twisted) steel wires in the corner in which the two steel wires meet or separate which together delimit the hexagonal mesh (all around). In particular, the hexagonal mesh has two aperture angles spanning the hexagonal mesh in the longitudinal direction, In particular, the two aperture angles spanning the hexagonal mesh in the longitudinal direction are at least 70 , preferably at least 80 and preferentially at least 90 . In particular, the two aperture angles spanning the hexagonal mesh in the longitudinal direction are at least substantially equal. "Substantially equal" is in particular to mean, in this context, a congruence of the aperture angles in terms of size with a maximal deviation of 8 , preferably of 6 , advantageously of 4 and preferentially of 2 . The longitudinal direction of the hexagonal mesh in particular extends parallel to the main extension direction of the hexagonal mesh.
So, if the opposite-situated, in particular middle, aperture angles of the hexagonal mesh, which span the hexagonal mesh in the longitudinal direction, differ from each other by maximally 8 , preferably by maximally 6 , preferentially by maximally 4 , advantageously a high level of symmetry of the steel wire netting, in particular of the hexagonal meshes, is achievable, as a result of which it is advantageously possible to attain especially even load-bearing capacity in at least two pulling directions of the steel wire netting which are situated opposite each other along the mesh height, preferably in all directions of the steel wire netting.
If the hexagonal meshes have an, in particular average, mesh width of approximately 60 mm, approximately 80 mm or approximately 100 mm, it is

- 9 -advantageously possible to obtain high and quick acceptance of the steel wire netting in planning and construction projects. Advantageously, in this way simple reinforcement of already planned or designed constructions will be enabled, in particular due to particularly simple re-planning. In particular, the hexagonal meshes have a mesh size and/or mesh shape compliant with the standard EN
10223-3:2013.1n particular, the steel wire herein has a diameter of 2 mm, 3 mm, 4 mm or with a value between 2 mm and 4 mm.
If moreover the high-tensile steel of the steel wires is implemented of a stainless type of steel or at least has a sheath made of a stainless type of steel, it is possible to maintain particularly high corrosion resistance and hence a particularly long lifetime of the constructions comprising the steel wire netting.
Lifetimes of 100 years and more tend to be requested by customers, and are theoretically achievable by a utilization of stainless types of steel. In particular, the steel wire is made of a stainless steel having a material number according to the standard DIN
EN 10027-2:2015-07 which is between 1.4001 and 1.4462, for example of a stainless steel having one of the DIN EN 10027-2:2015-07 material numbers 1.4301, 1.4571, 1.4401, 1.4404 or 1.4462.
If alternatively the steel wires have a corrosion protection coating or a corrosion protection overlay, it is also advantageously possible to achieve high corrosion resistance together with a long lifetime, wherein costs can be kept at a low level in comparison to stainless steel wires. In particular, the corrosion protection coating is realized as a galvanization, as a ZnAl coating, as a ZnAlMg coating or as a comparable metallic corrosion protection coating. In particular, the corrosion protection overlay is realized as a non-metallic overlay surrounding the steel wire in a circumferential direction, for example as a plastic envelope (e. g. PVC) or as a graphene envelope.
It is further proposed that the corrosion protection coating is realized at least as a class B corrosion protection coating according to the standard DIN EN 10244-2:2001-07, preferably as a class A corrosion protection coating according to the

- 10 -standard DIN EN 10244-2:2001-07. This advantageously allows attaining particularly high corrosion resistance and thus a long lifetime. Preferably not only the starting materials, i. e. the non-bent steel wires, have the class B or class A
corrosion protection coating but the finished steel wire netting as well. In particular, in a test run with an alternating climate test, at least a portion of the steel wire netting with the corrosion protection layer has a corrosion resistance of more than 1,680 hours, preferably of more than 2,016 hours, advantageously of more than 2,520 hours, preferentially of more than 3,024 hours and particularly preferentially of more than 3,528 hours. An "alternating climate test" is in particular to mean a corrosion resistance test of the corrosion protection, in particular of the corrosion protection layer, preferably following the specifications given by VDA [German Association of the Automotive Industry] in their Recommendation VDA 233-102, which in particular provides, at least in a sub-period, a fogging and/or spraying of at least one test piece with a salt spray fog and/or exposing the test piece, at least in a sub-period, to a temperature change from room temperature to sub-zero temperatures. By varying a temperature, a relative humidity and/or a salt concentration which the test piece is exposed to, it is advantageously possible to improve a reliability of a test method. In particular, test conditions can be adapted closer to real conditions which the wire netting device is exposed to, in particular when used in the field. The test piece is preferably embodied as a sub-portion of a wire that is at least substantially identical to the wire of the wire netting device, preferentially as a sub-portion of the wire of the wire netting device. The alternating climate test is preferably carried out in accordance with the customary edge conditions for alternating climate tests, which are known to anyone skilled in the art and which are in particular listed in VDA Recommendation 233-102 of J
une 30, 2013. The alternating climate test is in particular carried out in a test chamber.
The conditions in an interior of the test chamber during the alternating climate test are in particular strictly controlled conditions. In particular, strict specifications regarding temperature profiles, relative air humidity and periods of fogging with salt spray fog must be followed in the alternating climate test. A test cycle of the alternating climate test is in particular divided into seven cycle sections. A
test

- 11 -cycle of the alternating climate test in particular takes one week. One cycle section in particular takes one day. A test cycle comprises three different test sub-cycles.
A test sub-cycle implements a cycle section. The three test sub-cycles comprise at least one cycle A, at least one cycle B and/or at least one cycle C. During a test cycle, test sub-cycles are realized consecutively in the following order:
cycle B, cycle A, cycle C, cycle A, cycle B, cycle B, cycle A.
Cycle A in particular comprises a salt spraying phase. In the salt spraying phase a salt spray fog is in particular sprayed within the test chamber. In particular, the salt solution sprayed during cycle A is here in particular realized as a solution of sodium chloride in distillated water, which was preferably boiled prior to a preparation of the solution and which preferentially has an electrical conductivity of maximally 20 S/cm at (25 2) C, with a mass concentration in a range of (10 1) g/I. The test chamber for the alternating climate test in particular has an inner volume of at least 0.4 m3. In particular in an operation of the test chamber, the inner volume is homogeneously filled with a salt spray fog. The upper portions of the test chamber are preferably implemented in such a way that drops formed on the surface cannot fall onto a test piece. Advantageously a temperature is (35 0.5) C during a spraying of the salt spray fog, in particular within the test chamber, the temperature being preferably measured at a distance of at least 100 mm from a wall of the test chamber.
Cycle B in particular comprises a work phase, during which the temperature is maintained at room temperature (25 C) and the relative humidity is maintained at a room-typical relative air humidity (70 %). In the work phase in particular the test chamber can be opened and the test piece can be assessed and/or checked.
Cycle C in particular comprises a freezing phase. In the freezing phase in particular the test chamber temperature is maintained at a value below 0 C, preferably at -15 C.
A "corrosion resistance" is in particular to be understood as a durability of a material during a corrosion test, for example an alternating climate test, in

- 12 -particular in accordance with VDA recommendation 233-102 of J une 30, 2013, during which a functionality of a test piece is maintained, and/or preferably a time duration during which a threshold value of a corrosion parameter of a test piece is undershot during an alternating climate test. By "a functionality being maintained"
is in particular to be understood that material properties of a test piece which are relevant for a functionality of a wire netting, like a tear resistance and/or brittleness, remain substantially unchanged. By "a material property remain[ing]
substantially unchanged" is in particular to be understood that a change in a material parameter and/or in a material property amounts to less than 10 %, preferably less than 5 %, preferentially less than 31% and especially preferentially less than 1 % with respect to an initial value prior to the corrosion test.
Preferably the corrosion parameter is implemented as a percentage of an overall surface of a test piece, on which dark brown rust (DBR) is, in particular visually, perceivable.
The threshold value of the corrosion parameter is preferably 5 %. A corrosion resistance thus preferably indicates a time interval which passes until dark brown rust (DBR) is visually perceivable on 51% of an overall surface of a test piece, in particular an overall surface of a test piece that is exposed to the salt spray fog in the alternating climate test. Preferentially the corrosion resistance is the time that passes between a start of the alternating climate test and an occurrence of 5 %
DBR on the surface of the test piece.
In particular, already the production method of the corrosion-protection-coated steel wire nettings used is specifically adapted, such that the resulting steel wires have a high rupture resistance despite high tensile strengths and despite thick corrosion protection layers, and in particular survive the production process for the steel wire netting such that the resulting steel wire netting is free of rupturing and the corrosion protection layer remains unscathed. For this purpose, for example the coating temperature is specifically selected such that additional brittling of the coated high-tensile steel wires can be kept low. For this purpose, for example in a galvanization the temperature of the coating bath is specifically kept lower than usual. In particular, the temperature of the coating bath herein remains in each

- 13 -process step below 440 C, preferably below 435 C, advantageously below 430 C, preferentially below 425 C. At the same time the coating temperature of the coating bath herein remains above 421 C. In particular, extensive temperature control of the coating bath is necessary for this. In particular, additional leaking of carbon from the high-tensile steel wires during the coating process, influencing brittleness and strength of the steel wire, is taken into account here.
Moreover, a production method for the steel wire netting from the coated steel wires is preferably adapted specifically in such a way that a rupturing of the steel wire or a damaging of the corrosion protection layer while braiding the hexagonal meshes is prevented to the best possible extent. For this, in particular a twisting speed at which neighboring steel wires are twisted is reduced as compared to customary production processes. In particular, the twisting speed is at least 0.5 seconds per (180 ) twisting, preferably at least 0.75 seconds per (180 ) twisting and preferentially at least one second per (180 ) twisting.
In the case of a steel wire with a class B corrosion protection coating and with a wire diameter of approximately 2 mm, the area density of the corrosion protection layer is at least 115 g/m2. In the case of a steel wire with a class B
corrosion protection coating and with a wire diameter of approximately 3 mm, the area density of the corrosion protection layer is at least 135 g/m2. In the case of a steel wire with a class B corrosion protection coating and with a wire diameter of approximately 4 mm, the area density of the corrosion protection layer is at least 135 g/m2. In the case of a steel wire with a class B corrosion protection coating and with a wire diameter of approximately 5 mm, the area density of the corrosion protection layer is at least 150 g/m2. In the case of a steel wire with a class A
corrosion protection coating and with a wire diameter of approximately 2 mm, the area density of the corrosion protection layer is at least 205 g/m2. In the case of a steel wire with a class A corrosion protection coating and with a wire diameter of approximately 3 mm, the area density of the corrosion protection layer is at least 255 g/m2. In the case of a steel wire with a class A corrosion protection coating and with a wire diameter of approximately 4 mm, the area density of the corrosion

- 14 -protection layer is at least 275 g/m2. In the case of a steel wire with a class A
corrosion protection coating and with a wire diameter of approximately 5 mm, the area density of the corrosion protection layer is at least 280 g/m2.
In particular, the steel wire used and the corrosion protection layer applied onto the steel wire survive, in particular in at least one test run, without damages, in particular without rupturing, an N-fold twisting of the wire, wherein N may be determined, if applicable by rounding down, as B*R- .5-d- .5, and d is a diameter of the wire in mm, R is a tensile strength of the wire in N*mm-2 and B is a factor of at least 960 N .5 mm- .5, preferably at least 1,050 N .5 mm- .5, advantageously at least 1,200 N .5 mm- .5, preferentially at least 1,500 N .5 mm- .5, and especially preferentially at least 2,000 N .5 mm- .5. In particular, the twisting test is executed in accordance with the requirements of the standards DIN EN 10218-1:2012-03 and DIN EN 10264-2:2012-03. This in particular allows providing a selection process for a suitable wire that is significantly more strict and more specific with regard to a load-bearing capacity as compared to a twisting test in accordance with the standards DIN EN 10218-1:2012-03 and DIN EN 10264-2:2012-03. A
"twisting" is in particular to mean a twisting of a clamped-in wire around a longitudinal axis.
In particular, the steel wire used and the corrosion protection layer applied onto the steel wire survive, in particular in at least one test run, without damages, in particular without rupturing, an M-fold back-and-forth bending of the wire around at least one bending cylinder that has a diameter of maximally 8d, preferably no more than 6d, preferentially maximally 4d and particularly preferably no more than 2d, by at least 900 respectively, in opposite directions, wherein M can be determined, if applicable by rounding-down, to be C* R- .5* d- .5, and wherein d is a diameter of the wire in mm, R is a tensile strength of the wire given in N
mm-2 and C is a factor of at least 350 N .5 mm- .5, preferably at least 600 N .5 mm-.5, advantageously at least 850 N .5 mm- .5, preferentially at least 1,000 N .5 mm-.5 and particularly preferably at least 1,300 N .5 mm- .5. In particular, the reverse bend test is executed in accordance with the standards DIN EN 10218-1:2012-03

- 15 -and DIN EN 10264-2:2012-03. This in particular allows providing a selection process for a suitable wire that is considerably stricter and/or more specific regarding a load-bearing capacity than a reverse bend test according to the standards DIN EN 10218-1:2012-03 and DIN EN 10264-2:2012-03. In the reverse bending, the wire is preferably bent around two opposite-situated bending cylinders which are implemented identically.
Beyond this it is proposed that at least two sub-pieces of the steel wires survive without rupturing, in particular in a test run, a screw-like winding around each other, comprising at least N+1 twistings, preferably N+2 twistings and preferentially N+4 twistings, wherein N is (if applicable by rounding down) a number of twistings of the steel wires delimiting the hexagonal meshes to opposite sides. This advantageously permits ensuring a high rupture resistance of the steel wire netting, in particular also in the case of events initiating additional deformation of the steel wire nettings. It is moreover advantageously possible to make sure that the steel wires used for the production of the steel wire netting do not rupture during the production process, in particular not during a twisting, thus causing production stoppage and/or damaging of production installations. It is moreover advantageously possible to make sure that an overbending of the steel wires used, which is necessary for the production of the steel wire netting having the advantageous mesh width / mesh height ratio of at least 0.75, is feasible, thus basically enabling a production of the steel wire netting having the advantageous mesh width / mesh height ratio of at least 0.75.
Furthermore, a production device is proposed for braiding a steel wire netting with hexagonal meshes, in particular a hexagonal netting, from steel wires comprising a high-tensile steel, with at least one array of twisting units for an alternating twisting of steel wires with further steel wires which are guided on respectively opposite sides of the steel wires, and with at least one rotatable roller, which is supported downstream of the twisting units and has on a sheath surface dogs which are configured to engage into the newly braided hexagonal meshes, thus pushing or pulling the steel wire netting forward, wherein the twisting units are

- 16 -configured to over-rotate the steel wires and/or the rotatable roller is configured to over-expand a mesh width of the hexagonal meshes, in particular as compared to the mesh width of a finished hexagonal mesh. Advantageously, a production of a steel wire netting from high-tensile steel wires with an improved mesh geometry, in particular with standard-compliant mesh width / mesh height ratios, is enabled in this way. In particular, the twisting units are configured to produce the twisted regions which partly delimit the hexagonal meshes. In particular, each twisting unit comprises two half-shell twisting elements, each of which guides a steel wire and which are alternatingly rotated around a shared rotation axis and around two separate rotation axes for a twisting, wherein in particular in rotating separately from each other, each of the half-shells is combined with a half-shell of a neighboring twisting unit. In particular, a rotation axis of the rotatable roller is oriented at least substantially perpendicularly to the rotation axes of the twisting units. By the twisting units being configured to "over-rotate" the steel wires, is in particular to be understood that a rotation angle swept over by the twisting units during a twisting process is larger than a total twisting angle of the twisted regions delimiting the hexagonal meshes of the finished steel wire netting. By the rotatable roller being configured to "over-expand" the mesh width of the hexagonal mesh, is in particular to be understood that a mesh width enforced on the steel wire netting by the rotatable roller, in particular by the dogs of the rotatable roller, is larger than a mesh width of the hexagonal meshes of the finished steel wire netting.
"Configured" is in particular to mean specifically designed and/or equipped.
By an object being configured for a certain function is in particular to be understood that the object fulfills and/or executes said certain function in at least one application state and/or operation state.
If herein the over-rotating of the intertwisted steel wires and/or the over-expanding of the hexagonal meshes is configured to compensate a rebound of the high-tensile steel wires, which are substantially more elastic as compared to a non-high-tensile steel, advantageously a production of a steel wire netting from high-tensile steel wires is enabled with an improved mesh geometry, in particular with

- 17 -standard-compliant mesh width / mesh height ratios, which was not possible with customary methods. In particular, a dimension of an over-rotating/twisting is selected such that a rebound effect that corresponds to the material, the tensile strength and the wire thickness of the respective steel wire used is compensated as completely as possible.
In this context it is proposed that the twisting units are configured to twist the steel wires at least M-fold with one another, wherein M is given by the formula M = U + 0.5 * G, and U is an uneven integer 3, which preferably corresponds to a number of twistings within a twisted region of the finished steel wire netting that delimits a hexagonal mesh, and wherein G is any real number 1 and 5 3. As a result, sufficient compensation of the rebound effect of the high-tensile steel wire, in particular having a thickness between 2 mm and 4 mm, is advantageously attainable. Preferably G 1.5, preferably 2.
In a further aspect of the invention which, taken on its own or in combination with at least one, in particular in combination with one of the remaining aspects of the invention, in particular in combination with any number of the remaining aspects of the invention, it is proposed that the production device comprises a stretching unit, which is integrated in the rotatable roller, which is supported downstream of or is arranged separately from the rotatable roller, and which is configured to stretch a finished steel wire netting, in particular hexagonal netting, at least in a direction parallel to the mesh width, preferably at least by 30 %, preferably at least by 50 %
and particularly preferably at least by 55 %. In particular, the stretching unit is configured to simultaneously grip and stretch several meshes of the steel wire netting which are arranged behind one another or spaced apart behind one another in a direction running parallel to the mesh width. Preferentially at least a large portion of all hexagonal meshes of the mesh netting is stretched directly. By the term "stretched directly" is in particular to be understood that the stretching unit contacts the meshes directly and stretches them independently from a stretching of further meshes. A "large portion" is in particular to mean 10 %, preferably 20 %,

- 18 -advantageously 30 %, especially advantageously 50 %, preferentially 66 % and particularly preferentially 85 %.
Moreover, a production method is proposed for a braiding of a steel wire netting with hexagonal meshes, in particular a hexagonal netting, in particular by means of a production device. This advantageously allows providing a steel wire netting made of high-tensile steel wires with a particularly advantageous mesh geometry, which is in particular already widely in use and well proven in the non-high-tensile field.
If during production of the steel wire netting the steel wires are over-rotated in twisted regions of the steel wire netting and/or if the hexagonal meshes are over-expanded in a direction parallel to the mesh width, this advantageously enables a production of a steel wire netting from high-tensile steel wires with an improved mesh geometry, in particular with standard-compliant mesh width / mesh height ratios, which was not realizable with methods known until now.
The steel wire netting according to the invention, the production device according to the invention and the production method according to the invention shall herein not be limited to the application and implementation described above. In particular, in order to realize a functionality that is described here, the steel wire netting according to the invention, the production device according to the invention and the production method according to the invention may comprise a number of individual elements, components and units that differs from a number given here.
Drawings Further advantages will become apparent from the following description of the drawings. In the drawings four exemplary embodiments of the invention are illustrated. The drawings, the description and the claims contain a plurality of features in combination. Someone skilled in the art will purposefully also consider the features separately and will find further expedient combinations.

- 19 -It is shown in:
Fig. 1 a portion of a steel wire netting with hexagonal meshes, which constitutes the prior art, Fig. 2 a schematic plan view of a steel wire netting with hexagonal meshes according to the invention, Fig. 3 a schematic section through a steel wire of the steel wire netting with a corrosion protection overlay, Fig. 4 a schematic section through a steel wire of the steel wire netting with a corrosion protection coating, Fig. 5 a schematic illustration of a test device for carrying out twisting tests, Fig. 6 a schematic side view of a production device for a braiding of the steel wire netting with the hexagonal meshes, Fig. 7 a further schematic illustration of the production device from a perspective view, Fig. 8 a schematic, partly sectioned detail view of a portion of the production device, with a rotatable roller and with twisting units, Fig. 9 a schematic, partly sectioned detail view of a portion of the production device, with an alternative rotatable roller, Fig. 10 a schematic flowchart of a production method for a braiding of the steel wire netting with the hexagonal meshes, Fig. 11 a schematic plan view of an alternative steel wire netting according to the invention, Fig. 12 a schematic section through a steel wire of a further alternative steel wire netting according to the invention, and Fig. 13 a schematic section through a steel wire of an additional further alternative steel wire netting according to the invention.

- 20 -Description of the exemplary embodiments Figure 1 shows a section of a steel wire netting 254 with hexagonal meshes 216, which constitutes the prior art and is currently produced and distributed by the company of the applicant of the patent document PL 235814 B1 (Nector Sp. z o.o., Krakow, Poland). The steel wire netting 254 is produced from steel wires 210, 212, 214, which are made of high-tensile steel. The steel wire netting 254 has a mesh width 218 and a mesh height 220. A mesh width / mesh height ratio of the prior art steel wire netting 254 is considerably less than 0.75. The mesh width / mesh height ratio of the prior art steel wire netting 254 is approximately 0.5.
Figure 2 shows schematically a steel wire netting 54a according to the invention.
The steel wire netting 54a is configured for an application for civil engineering purposes. The steel wire netting 54a is configured for an application in the field of protection from natural hazards. The steel wire netting 54a is realized as a hexagonal netting. The steel wire netting 54a comprises hexagonal meshes 16a.
The steel wire netting 54a is made of steel wires 10a, 12a, 14a. The steel wires 10a, 12a, 14a are made of a high-tensile steel. The high-tensile steel which the steel wires 10a, 12a, 14a are made of has a tensile strength of at least 1,700 N/mm2 and maximally 2,150 N/mm2. In the example shown the steel wires 10a, 12a, 14a are made of a high-tensile steel with a tensile strength of approximately 1,950 N/mm2. In addition, it is conceivable that the steel wires 10a, 12a, 14a made of the high-tensile steel have a (non-high-tensile) corrosion protection overlay 50'a (see figure 4) or a (non-high-tensile) corrosion protection coating 48a (see figure 3). If the steel wires 10a, 12a, 14a have the corrosion protection coating 48a, the corrosion protection coating 48a is realized at least as a class B corrosion protection coating according to the standard 10244-2:2001-07.
In the case shown exemplarily in figure 3, the corrosion protection coating 48a is realized as a class A corrosion protection coating according to the standard DIN
EN 10244-2:2001-07.

- 21 -In order to form the hexagonal meshes 16a, the steel wires 10a, 12a, 14a of the steel wire netting 54a are alternatingly twisted with neighboring steel wires 10a, 12a, 14a of the steel wire netting 54a. The intertwisted steel wires 10a, 12a, 14a form twisted regions 24a. The twisted regions 24a in each case comprise at least three consecutive twistings 28a, 38a, 40a. Each twisting 28a, 38a, 40a comprises a 1800 winding of a steel wire 10a, 12a, 14a of the steel wire netting 54a around a further steel wire 10a, 12a, 14a of the steel wire netting 54a. In the example shown in figure 2, the twisted regions 24a comprise precisely three twistings 28a, 38a, 40a. Each of the twistings 28a, 38a, 40a has a length 26a. The lengths 26a of the twistings 28a, 38a, 40a are approximately equal. The forms of the twistings 28a, 38a, 40a are approximately equal. The average length 26a of the twistings 28a, 38a, 40a within the twisted regions 24a of several of the hexagonal meshes 16a is smaller than 1.1 cm.
The hexagonal meshes 16a of the steel wire netting 54a have a mesh height 20a.
The mesh height 20a is measured perpendicularly to the mesh width 18a. The mesh height 20a is implemented as a largest aperture length of the hexagonal meshes 16a. The mesh height 20a is measured between a corner 66a of the hexagonal mesh 16a, in which a twisting 28a, 38a, 40a (differing from the twisted regions 24a) of the two steel wires 10a, 12a, which delimit the hexagonal mesh 16a all around, starts, and a further corner 68a of the hexagonal mesh 16a, in which the twisting 28a, 38a, 40a (differing from the twisted regions 24a) of the steel wires 10a, 12a, which delimit the hexagonal mesh 16a all around, ends.
The twisted regions 24a respectively delimit the hexagonal meshes 16a on two opposite-situated sides. Each twisted region 24a (possible exception: an edge of the steel wire netting 54a) delimits two neighboring hexagonal meshes 16a at the same time. Each of the twisted regions 24a has a length 22a. The lengths 22a of the twisted regions 24a are approximately equal. The average length 22a of the twisted regions 24a delimiting the hexagonal meshes 16a amounts to at least % of the average mesh height 20a of several hexagonal meshes 16a of the 30 steel wire netting 54a.

- 22 -The hexagonal meshes 16a of the steel wire netting 54a have a mesh width 18a.
The mesh width 18a is implemented as a shortest distance between the two twisted regions 24a delimiting a hexagonal mesh 16a. The average length 22a of the twisted regions 24a delimiting the hexagonal meshes 16a amounts to at least 50 % of the average mesh width 18a of several hexagonal meshes 16a of the steel wire netting 54a. The average mesh width 18a of the hexagonal meshes 16a typically amounts to approximately 60 mm, approximately 80 mm or approximately 100 mm. In the case shown exemplarily in figure 2, the mesh width 18a is approximately 80 mm.
An average ratio of the average mesh width 18a of several hexagonal meshes 16a of the steel wire netting 54a and the average mesh height 20a of the hexagonal meshes 16a is at least 0.75. A mesh width / mesh height ratio formed from the mesh width 18a and the mesh height 20a is at least 0.75. In the case shown exemplarily in figure 2, the mesh width / mesh height ratio is 0.8.
The hexagonal meshes 16a have a first aperture angle 44a that spans the hexagonal meshes 16a in a longitudinal direction 42a of the hexagonal meshes 16a. The longitudinal direction 42a points in a production direction of the steel wire netting 54a, i. e. from a twisted region 24a that was produced later towards a twisted region 24a that was produced earlier. Alternatively, the longitudinal direction 42a may point in the opposite direction. The first aperture angle 44a spans the hexagonal mesh 16a in a corner 66a that is situated further frontwards in the longitudinal direction 42a. The hexagonal meshes 16a have a second aperture angle 70a that spans the hexagonal meshes 16a in the longitudinal direction 42a. The second aperture angle 70a spans the hexagonal mesh 16a in a corner 68a that is situated further rearwards in the longitudinal direction 42a. The two aperture angles 44a, 70a are situated in opposed corners 66a, 68a of the hexagonal meshes 16a.
The average first aperture angle 44a of several hexagonal meshes 16a of the steel wire netting 54a is at least 70 . In the example shown in figure 2, the first aperture

- 23 -angle 44a is approximately 900. The average second aperture angle 70a of several hexagonal meshes 16a of the steel wire netting 54a is at least 70 . In the example shown in figure 2, the second aperture angle 70a is approximately 90 .

The opposite-situated average aperture angles 44a, 70a of the hexagonal meshes 16a, which span the hexagonal meshes 16a in the longitudinal direction 42a, differ from each other by maximally 8 . In the example shown in figure 2, the opposite-situated aperture angles 44a, 70a of the hexagonal mesh 16a are approximately equal.
Viewed along the longitudinal direction 42a, the two steel wires 10a, 12a, which delimit a hexagonal mesh 16a of the steel wire netting 54a all around, in each case have an entry curvature 30a on respectively opposite-situated sides of the hexagonal mesh 16a, in a transition 72a in which the respective steel wire 10a, 12a passes from an at least substantially straight section 32a of the respective steel wire 10a, 12a that delimits the hexagonal mesh 16a to a twisted region 24a of the steel wire 10a, 12a that delimits the hexagonal mesh 16a. Viewed along the longitudinal direction 42a, the two steel wires 10a, 12a, which delimit a hexagonal mesh 16a of the steel wire netting 54a all around, in each case have an exit curvature 34a on respectively opposite sides of the hexagonal mesh 16a, in a further transition 74a (differing from the transition 72a) in which the respective steel wire 10a, 12a passes from the twisted region 24a that delimits the hexagonal mesh 16a to an at least substantially straight further section 36a of the steel wire 10a, 12a that delimits the hexagonal mesh 16a. The average entry curvature 30a and the average exit curvature 34a of the steel wires 10a, 12a, 14a of several hexagonal meshes 16a are approximately equal.
The steel wires 10a, 12a, 14a of the steel wire netting 54a have a rupture resistance suitable for the production of the hexagonal meshes 16a with the mesh width / mesh height ratio of 0.75 or more. The steel wires 10a, 12a, 14a of the steel wire netting 54a are realized in such a way that two sub-pieces of the steel wires 10a, 12a, 16a survive in a first twisting test run a screw-like winding around each other comprising at least N+1 twistings, wherein N is, if applicable by

- 24 -rounding down, a number of twistings of the steel wires 10a, 12a, 14a delimiting the hexagonal meshes 16a to opposite sides. In the example shown in figure 2, the steel wires 10a, 12a, 14a thus survive at least four twistings. In particular, for each steel wire batch the first twisting test run is executed before usage for the production of a steel wire netting 54a. For this purpose, two sub-pieces of the steel wires 10a, 12a, 14a of the steel wire batch are clamped into a test device 76a at opposite ends (see figure 5) and are twisted with each other until a wire rupture of at least one of the steel wires 10a, 12a, 14a is detected.
Moreover, the steel wires 10a, 12a of the steel wire netting 54a are realized in such a way that in a second twisting test run two sub-pieces of the steel wires 10a, 12a, 14a survive a screw-like winding and unwinding of the steel wires 10a, 12a, 14a around each other, comprising at least three, preferably at least five and preferentially at least seven back-and-forth twistings. The test pieces of the steel wires 10a, 12a, 14a are herein alternatingly wrapped with each other by respectively 180 and then unwrapped. An 1800 twisting in one of the two twisting directions is herein counted as one back-and-forth twisting. For an execution of the second twisting test run, the two sub-pieces of the steel wires 10a, 12a, 14a of the steel wire batch are also clamped into the test device 76a at opposite ends and are twisted back and forth until a wire rupture of at least one of the steel wires 10a, 12a, 14a is detected. This advantageously allows, on the one hand, ensuring that the steel wires 10a, 12a, 14a do not break during the production of the steel wire netting 54a according to the invention, in particular in an over-rotating of the steel wires 10a, 12a, 14a and/or do not break in an over-expansion of the steel wire netting 54a. On the other hand, it is in this way advantageously possible to state that the wire netting 54a according to the invention is capable of providing a sufficient protective effect as it has, for example, a sufficiently high rupture resistance also in the case of an event (for example a rockfall) involving plastic and/or elastic deformation.
Figure 5 shows a schematic illustration of the test device 76a for carrying out the first twisting test run and/or for carrying out the second twisting test run.
The test

- 25 -device 76a comprises two steel wire holding devices 78a, 80a for a positionally fix and rotationally fix holding of a pair of steel wires 10a, 12a. Prior to a start of the respective twisting test run, the steel wires 10a, 12a held in the steel wire holding devices 78a, 80a are guided side by side and parallel to each other. When the respective twisting test run is carried out, one of the two steel wire holding devices 78a, 80a is held in a rotationally fix manner while the other one of the two steel wire holding devices 78a, 80a is rotated around a rotation axis that runs parallel to the initial longitudinal directions 82a of the steel wires 10a, 12a held by the steel wire holding devices 78a, 80a.
Figure 6 shows a schematic side view of a production device 52a for a braiding of the steel wire netting 54a having the hexagonal meshes 16a, in particular for a braiding of a hexagonal netting, from the steel wires 10a, 12a, 14a comprising the high-tensile steel. The production device 52a comprises a first wire supply device 84a for supplying at least part of the starting material, for example at least the steel wire 10a. The first wire supply device 84a is configured to receive at least one bobbin 86a with the wound-up high-tensile steel wire 10a so as to be rotatable, in particular unrollable. The production device 52a comprises a wire alignment device 88a. The wire alignment device 88a is configured for at least partially straightening the previously rolled-up steel wire 10a. The production device 52a comprises a second wire supply device 90a. In the second wire supply device 90a the steel wire 12a is wound up in spiral fashion.
The production device 52a comprises an array of twisting units 56a, 58a (see also figure 8). The twisting units 56a, 58a are configured for twisting the steel wires 10a, 12a fed from the wire supply devices 84a, 90a with each other. The twisting units 56a, 58a are configured for twisting respectively one steel wire 10a alternatingly with further steel wires 12a, 14a, which are guided on respectively opposite-situated sides of the steel wire 10a. The production device 52a comprises a rotatable roller 60a. The rotatable roller 60a is arranged within the production device 52a downstream of the twisting units 56a, 58a. The rotatable roller 60a is configured to push, respectively pull, the already intertwisted steel

- 26 -wires 10a, 12a, 14a, preferably pulling them away from twisting regions of the twisting units 56a, 58a. The rotatable roller 60a is configured for a continuous rotation. The production device 52a comprises a netting roll-up device 92a.
The netting roll-up device 92a is configured to accept the finished steel wire netting 54a from the rotatable roller 60a and to roll the steel wire netting 54a into netting rolls 94a.
Figure 7 shows a further schematic illustration of the production device 52a in a perspective view.
Figure 8 shows schematically a partly sectioned detail view of a portion of the production device 52a. In the section shown in figure 8, three twisting units 56a, 58a, 104a are illustrated. A first twisting unit 56a comprises two twisting elements 96a, 98a. A second twisting unit 58a, which is arranged next to the first twisting unit 56a, also comprises two twisting elements 100a, 102a. The twisting elements 96a, 98a, 100a, 102a of one of the twisting units 56a, 58a, 104a are in each case realized as half-shell sub-elements of a cylinder shape. Each twisting element 96a, 98a, 100a, 102a of one of the twisting units 56a, 58a, 104a guides a single steel wire 10a, 12a, 14a. The twisting elements 96a, 100a, which are situated to the front in figure 8, guide respectively one steel wire 10a, 14a that has been wound from the bobbin 86a and straightened. The twisting elements 98a, 102a, which are situated to the rear in figure 8, guide a steel wire 12a that has been wound up freely in spiral fashion. The twisting elements 98a, 102a, which are situated to the rear in figure 8, are arranged on a rail 106a that is supported so as to be longitudinally movable. The twisting elements 98a, 102a are guided along with the movement of the rail 106a. The rail 106a can be moved back and forth in both directions along a longitudinal axis of the rail 106a. The rail 106a can be moved back and forth in both directions parallel to a rotation axis 108a of the rotatable roller 60a. The rail 106a can be moved back and forth in both directions perpendicularly to rotation axes 110a of the twisting units 56a, 58a, 104a. In a movement of the rail 106a, different twisting elements 96a, 98a, 100a, 102a are brought together alternatingly. For example, first the two twisting elements 96a,

- 27 -98a belonging to the first twisting unit 56a are brought together and the corresponding steel wires 10a, 12a are twisted. Then one of the twisting elements 96a of the first twisting unit 56a is brought together, by the movement of the rail 106a, with one of the twisting elements 102a of the second twisting unit 58a.
The twisting elements 96a, 98a, 100a, 102a, after having been respectively brought together, rotate around a shared rotation axis 110a, as a result of which the steel wires 10a, 12a, 14a, guided respectively by the twisting elements 96a, 98a, 100a, 102a which were brought together, are twisted with one another. During the twisting and the switching of the rail 106a, the rotatable roller 60a rotates and while rotating pulls the steel wires 10a, 12a, 14a out of the twisting units 56a, 58a, 104a.
The twisting units 56a, 58a, 104a are configured to over-rotate the steel wires 10a, 12a, 14a during the twisting process in which the steel wires 10a, 12a, 14a are twisted with each other in order to form the twisted regions 24a. The over-rotation of the intertwisted steel wires 10a, 12a, 14a is configured to compensate, after the twisting process, a rebound of the high-tensile steel wires 10a, 12a, 14a, which are considerably more elastic as compared to a non-high-tensile steel. The over-rotation of the intertwisted steel wires 10a, 12a, 14a is configured for producing a planar steel wire netting 54a with hexagonal meshes 16a, which has narrowly wrapped twisted regions 24a. The twisting units 56a, 58a, 104a are configured for twisting the steel wires 10a, 12a, 14a with each other in the twisting process at least M-fold, wherein M is given by the formula M = U + 0.5 * G, and U is an uneven integer 3, and G is any real number 1 and 5 3. In the case shown by way of example, the twisting units 56a, 58a, 104a are configured for twisting the steel wires 10a, 12a, 14a in the twisting process more than 3.5-fold. In the case shown by way of example, the twisting units 56a, 58a, 104a are configured for twisting the steel wires 10a, 12a, 14a in the twisting process approximately 4-fold.
The rotatable roller 60a comprises on a sheath surface 62a dogs 64a. The dogs 64a are configured to engage into the newly braided hexagonal meshes 16a of the steel wire netting 54a, thus pushing or pulling the steel wire netting 54a forward in

- 28 -the running twisting process. The rotatable roller 60a is configured to over-expand the hexagonal meshes 16a in a direction of the mesh width 18a in comparison to the mesh width 18a of a finished hexagonal mesh 16a. The dogs 64a are configured to over-expand the hexagonal meshes 16a in the direction of the mesh width 18a. The dogs 64a have a shape which generates an over-expansion of the hexagonal meshes 16a in the direction of the mesh width 18a. A width of each dog 64a of the rotatable roller 60a is larger than the mesh width 18a of the finished steel wire netting 54a. The over-expansion of the hexagonal meshes 16a is configured to compensate a rebound of the high-tensile steel wires 10a, 12a, 14a, which are considerably more elastic as compared to a non-high-tensile steel.
Figure 9 schematically shows the portion of the production device 52a which is also shown in figure 8, with the production device 52a comprising an alternative rotatable roller 60'a. The production device 52a comprises a stretching unit 134a.
The stretching unit 134a is configured for a stretching of a finished steel wire netting 54a in directions parallel to the mesh width 18a. The stretching unit 134a is configured for a stretching of the finished steel wire netting 54a by at least 30 %. In the case illustrated exemplarily in figure 9, the stretching unit 134a is integrated in the alternative rotatable roller 60'a. The stretching unit 134a comprises stretching elements 112a, 114a, 116a. The stretching elements 112a, 114a, 116a are realized as projections in the rotatable roller 60'a. The stretching elements 112a, 114a, 116a are configured to engage into the hexagonal meshes 16a. The stretching elements 112a, 114a, 116a are configured to attack at the twisted regions 24a of the hexagonal meshes 16a and to pull the hexagonal meshes 16a apart in directions parallel to the mesh width 18a. For example, as a result of a back-and-forth movement of the stretching elements 112a, 114a, 116a during the rotation of the rotatable roller 60'a, the individual hexagonal meshes 16a of the steel wire netting 54a are temporarily over-expanded. Alternatively it is conceivable that the stretching unit 134a is supported downstream of the rotatable roller 60a or that the stretching unit 134a is arranged separately from the

- 29 -production device 52d comprising the rotatable roller 60a and the twisting units 56a, 58a, 104a.
Figure 10 shows a schematic flow chart of a production method for a braiding of the steel wire netting 54a having the hexagonal meshes 16a. In at least one method step 122a two steel wires 10a, 12a of a steel wire batch are clamped into the test device 76a and the first twisting test run and/or the second twisting test run are/is carried out. If the first twisting test run and/or the second twisting test run have/has been survived, the steel wires 10a, 12a of the steel wire batch that has now been tested are used for the production of a steel wire netting 54a according to the invention and/or are fed to the production device 52a.
In at least one further method step 120a the one (tested) steel wire 10a is fed to the first twisting unit 56a. In the method step 120a, the further (tested) steel wire 12a is fed to the first twisting unit 56a. In at least one method step 124a, the two steel wires 10a, 12a are twisted with each other. In the production of the steel wire netting 54a, in the method step 124a, the steel wires 10a, 12a are over-rotated in the twisted regions 24a of the steel wire netting 54a. In the method step 124a the steel wires 10a, 12a are over-rotated in the twisted regions 24a of the steel wire netting 54a at least by a half twist, preferably at least by a full twist.
After the over-rotation the over-rotated steel wires 10a, 12a automatically rebound by the over-rotated amount due to the high elasticity of high-tensile steel, such that the geometry according to the invention of the hexagonal meshes 16a is brought about.
In at least one further method step 118a the steel wire netting 54a that is being created is attacked at the twisted regions 24a by the dogs 64a of the rotatable roller 60a and is taken along with the movement of the rotatable roller 60a.
By the dogs 64a, in particular by the engagement of the dogs 64a in the hexagonal meshes 16a, the hexagonal meshes 16a are in the method step 118a over-expanded in directions parallel to the mesh width 18a. After passing the rotatable roller 60a, the over-expanded hexagonal meshes 16a automatically rebound at

- 30 -least by a portion of the expansion due to the high elasticity of high-tensile steel, such that the geometry according to the invention of the hexagonal meshes 16a is brought about.
Alternatively or additionally, in at least one further method step 126a the hexagonal meshes 16a of the finished steel wire netting 54a are additionally or alternatively stretched. In the method step 126a the hexagonal meshes 16a of the finished steel wire netting 54a are stretched by the stretching elements 112a, 114a, 116a which are integrated in the rotatable roller 60a or by stretching elements 112a, 114a, 116a which are implemented separately from the rotatable roller 60a. After the stretching by the stretching unit 134a, the stretched hexagonal meshes 16a automatically rebound at least by a portion of the stretching due to the high elasticity of high-tensile steel, such that the geometry according to the invention of the hexagonal meshes 16a is brought about.
In figures 11 to 13 three further exemplary embodiments of the invention are shown. The following descriptions and the drawings are essentially limited to the differences between the exemplary embodiments, wherein with regard to components having the same denomination, in particular to components having the same reference numerals, principally the drawings and/or the description of the other exemplary embodiments, in particular of figures 1 to 10, may be referred to. In order to distinguish between the exemplary embodiments, the letter a has been added to the reference numerals in figures 1 to 10. In the exemplary embodiments of figures 11 to 13, the letter a has been replaced by the letters b to d.
Figure 11 schematically shows an alternative steel wire netting 54b according to the invention. The steel wire netting 54b comprises hexagonal meshes 16b. The steel wire netting 54b is realized from steel wires 10b, 12b, 14b. The steel wires 10b, 12b, 14b are made of a high-tensile steel. For a formation of the hexagonal meshes 16b, the steel wires 10b, 12b, 14b of the steel wire netting 54b are alternatingly twisted with neighboring steel wires 10b, 12b, 14b of the steel wire

- 31 -netting 54b. The intertwisted steel wires 10b, 12b, 14b form twisted regions 24b.
The twisted regions 24b of the alternative steel wire netting 54b in each case comprise more than three consecutive twistings 28b, 38b, 40b, 128b, 130b. In the example shown in figure 11, the twisted regions 24b of the alternative steel wire netting 54b comprise five consecutive twistings 28b, 38b, 40b, 128b, 130b.
Figure 12 schematically shows a section through a steel wire 10c of a further alternative steel wire netting 54c according to the invention. The steel wire 10c is made of a high-tensile steel. The high-tensile steel of the steel wire 10c is implemented of a stainless type of steel.
Figure 13 schematically shows a section through a steel wire 10d of an additional further alternative steel wire netting 54d according to the invention. The steel wire 10d comprises a high-tensile steel. The steel wire 10d has a sheath 46d of a stainless type of steel. The steel wire 10d comprises a core 132d of a non-stainless type of steel. Either both subregions, the sheath 46d and the core 132d, or only the core 132d may be made of the high-tensile steel.

- 32 -Reference numerals steel wire 12 steel wire 14 steel wire 16 hexagonal mesh 18 mesh width mesh height 22 length 24 twisted region 26 length 28 twisting entry curvature 32 straight section 34 exit curvature 36 further straight section 38 twisting twisting 42 longitudinal direction 44 aperture angle 46 sheath 48 corrosion protection coating corrosion protection overlay 52 production device 54 steel wire netting 56 twisting unit 58 twisting unit roller 62 sheath surface 64 dog 66 corner

- 33 -68 corner 70 aperture angle 72 transition 74 transition 76 test apparatus 78 steel wire holding apparatus 80 steel wire holding apparatus 84 first wire supply device 86 bobbin 88 wire alignment direction 90 second wire supply device 92 netting roll-up device 94 netting roll 96 twisting element 98 twisting element 100 twisting element 102 twisting element 104 twisting unit 106 rail 108 rotation axis 110 rotation axis 112 stretching element 114 stretching element 116 stretching element 118 method step 120 method step 122 method step 124 method step 126 method step 128 twisting

- 34 -130 twisting 132 core 134 stretching unit 210 steel wire 212 steel wire 214 steel wire 216 hexagonal mesh 218 mesh width 220 mesh height 254 steel wire netting

Claims

1. A hexagonal netting made of steel wires (10a-d, 12a-d, 14a-d) with hexagonal meshes (16a-d), in particular for civil engineering purposes, preferably for an application in the field of protection from natural hazards, wherein the steel wires (10a-d, 12a-d, 14a-d) are alternatingly twisted with neighboring steel wires (10a-d, 12a-d, 14a-d) and wherein the steel wires (10a-d, 12a-d, 14a-d) are formed from a high-tensile steel or at least have a wire core made of a high-tensile steel, characterized in that an, in particular average, ratio calculated from an, in particular average, mesh width (18a-d) of the hexagonal meshes (16a-d) and an, in particular average, mesh height (20a-d) of the hexagonal meshes (16a-d), measured perpendicularly to the mesh width (18a-d), amounts to at least 0.8, wherein the mesh width (18a-d) is a distance between two twisted regions (24a-d) which delimit a hexagonal mesh (16a-d), which extend at least substantially parallel to each other and which are situated on opposite sides of the hexagonal mesh (16a-d), wherein the mesh height is a distance between two corners (66a-d, 68a-d) of the hexagonal mesh (16a-d) which are situated opposite each other in a direction parallel to a main extension direction of the twisted region (24a-d), and wherein the high-tensile steel of the steel wires (10a-d, 12a-d, 14a-d) has a tensile strength of at least 1,560 N/mm2.

2. The hexagonal netting according to claim 1, characterized in that the high-tensile steel of the steel wires (10a-d, 12a-d, 14a-d) has a tensile strength of at least 1,700 N/mm2 and preferentially of at least 1,950 N/mm2.

3. The hexagonal netting according to one of the preceding claims, characterized in that an, in particular average, length (22a-d) of a twisted region (24a-d) delimiting a hexagonal mesh (16a-d) is at least 30 %, preferably at least 35 %, of the, in particular average, mesh height (20a-d).

4. The hexagonal netting according to one of the preceding claims, characterized in that an, in particular average, length (22a-d) of a twisted region (24a-d) delimiting a hexagonal mesh (16a-d) is at least 50 %, preferably at least 55 % and preferentially at least 60 % of the, in particular average, mesh width (18a-d).

5. The hexagonal netting according to one of the preceding claims, characterized in that an, in particular average, length (26a-d) of a twisting (28a-d, 38a-d, 40a-d) within a twisted region (24a-d) delimiting a hexagonal mesh (16a-d) is less than 1.1 cm, preferably less than 1 cm.

6. The hexagonal netting according to one of the preceding claims, characterized in that a twisted region (24b-d) delimiting a hexagonal mesh (16b-d) comprises more than three consecutive twistings (28b-d, 38b-d, 40b-d, 128b-d, 130b-d).

7. The hexagonal netting according to one of the preceding claims, characterized in that at least one, in particular average, aperture angle (44a-d, 70a-d) of the hexagonal mesh (16a-d), spanning the hexagonal mesh (16a-d) in a longitudinal direction (42a-d), is at least 700, preferably at least 80 and preferentially at least 900, wherein the longitudinal direction (42a-d) of the hexagonal mesh (16a-d) runs parallel to a main extension direction of the hexagonal mesh (16a-d).

8. The hexagonal netting according to one of the preceding claims, characterized in that the hexagonal meshes (16a-d) have an, in particular average, mesh width (18a-d) of approximately 60 mm, approximately 80 mm or approximately 100 mm.

g. The hexagonal netting according to one of the preceding claims, characterized in that the high-tensile steel of the steel wires (10c-d, 12c-d, 14c-d) is implemented of a stainless type of steel or at least has a sheath (46d) of a stainless type of steel.

10. The hexagonal netting according to one of the preceding claims, characterized in that the steel wires (10a, 12a, 14a; 10b, 12b, 14b) have a corrosion protection coating (48a; 48b) or a corrosion protection overlay (50'a; 50'b).

11. The hexagonal netting according to claim 10, characterized in that the corrosion protection coating (48a; 48b) is realized at least as a class B
corrosion protection coating according to the standard DIN EN 10244-2:2001-07, preferably as a class A corrosion protection coating according to the standard DIN EN 10244-2:2001-07.

12. The hexagonal netting according to one of the preceding claims, characterized in that at least two sub-pieces of the steel wires (10a-d, 12a-d, 14a-d) survive without rupturing, in particular in a test run, a screw-like winding around each other, comprising at least N+1 twistings, preferably N+2 twistings and preferentially N+4 twistings, wherein N is, if applicable by rounding down, a number of twistings of the steel wires (10a-d, 12a-d, 14a-d) delimiting the hexagonal meshes (16a-d) to opposite sides.

13. A production device (52a-d) for a braiding of a hexagonal netting with hexagonal meshes (16a-d) from steel wires (10a-d, 12a-d, 14a-d) cornprising a high-tensile steel, according to one of the preceding claims, with at least one array of twisting units (56a-d, 58a-d, 104a-d) for an alternating twisting of steel wires (10a-d, 12a-d, 14a-d) with further steel wires (10a-d, 12a-d, 14a-d) which are guided on respectively opposite sides of the steel wires (10a-d, 12a-d, 14a-d), and with at least one rotatable roller (60a-d: 60'a-d), which is supported downstream of the twisting units (56a-d; 58a-d, 104a-d) and has on a sheath surface (62a-d) dogs (64a-d) configured to engage into the newly braided hexagonal meshes (16a-d), thus pushing or pulling the hexagonal netting forward, characterized in that the twisting units (56a-d; 58a-d, 104a-d) are configured to over-rotate the steel wires (10a-d, 12a-d, 14a-d) such that a rotation angle swept over by the twisting units (56a-d, 58a-d, 104a-d) during a twisting process is larger than a total twisting angle of the twisted regions (24a-d) delimiting the hexagonal meshes (16a-d) of the finished hexagonal netting, and/or that the rotatable roller (60a-d: 60'a-d) is configured to over-expand a mesh width (18a-d) of the hexagonal meshes (16a-d), in particular as compared to the mesh width (18a-d) of a finished hexagonal mesh (16a-d), by a stretching unit (134a-d), which is integrated in the rotatable roller (60a-d, 60'a-d), which is supported downstream of the rotatable roller (60a-d, 60'a-d) or is arranged separately, being configured to stretch a finished hexagonal netting at least in a direction parallel to the mesh width (18a-d) at least by 30 %.

14. The production device (52a-d) according to claim 13, characterized in that the over-rotating of the intertwisted steel wires (10a-d, 12a-d, 14a-d) and/or the over-expanding of the hexagonal meshes (16a-d) is configured to compensate a rebound of the high-tensile steel wires (10a-d, 12a-d, 14a-d), which are substantially more elastic as compared to a non-high-tensile steel.

15. The production device (52a-d) according to claim 13 or 14, characterized in that the twisting units (56a-d, 58a-d) are configured to twist the steel wires (10a-d, 12a-d, 14a-d) at least M-fold with one another, wherein M is given by the formula M = U + 0.5 * G, and U is an uneven integer 3, which preferably corresponds to a number of twistings (28a-d, 38a-d, 40a-d) within a twisted region (24a-d) of the finished hexagonal netting which delimits a hexagonal mesh (16a-d), and wherein G is any real number 1 and ~ 3.

16. A production method for a braiding of a hexagonal netting with hexagonal meshes (16a-d) according to one of claims 1 to 12, in particular by means of a production device (52a-d) according to one of claims 13 to 15, wherein during the production of the hexagonal netting the steel wires (10a-d, 12a-d, 14a-d) are over-rotated in twisted regions (24a-d) of the hexagonal netting, and/or wherein the hexagonal meshes (16a-d) are over-expanded in a direction parallel to the mesh width (18a-d) at least by 30 %.