EP4335953A1 - Antistatic core/sheath rope - Google Patents

Abstract

The invention relates to a rope (3) made of textile fiber material, comprising a rope core (6) and a sheath (7) surrounding the rope core (6), the rope (3) comprising at least one antistatic multifilament yarn (5) or one antistatic monofilament, which in the rope core (6), in the sheath (7), in an intermediate sheath (8) located between the rope core (6) and the sheath (7) and / or in one between the rope core (6) and the sheath (7) reinforcement is provided, the antistatic monofilament or individual filaments (12) of the antistatic multifilament yarn (5) each comprising a conductive fiber core (13) which is covered by a non-conductive plastic sheath (14).

Description

The invention relates to a rope made of textile fiber material, comprising a rope core and a sheath surrounding the rope core.

From the prior art, particularly in the area of application of cable cranes, core-sheath cables made of textile fiber material are known, which are usually not electrically conductive. Since these ropes generally cannot be grounded or discharged, depending on the application, static electricity occurs on the rope surface, as explained below.

Static electricity usually occurs when two surfaces separate. This can occur, for example, with running ropes that run over sheaves during operation. During operation, parts of the rope come into contact with the disks installed in the rope drive. These rope increments are deflected via the rope pulleys and after the desired change of direction in the rope drive, the rope runs off the rope pulley, i.e. the rope is separated from the rope pulley. By separating the surface of the rope from the surface of the sheave, both surfaces become charged with an electrical charge. If the pulley were sufficiently electrically conductive and grounded, the electrical charge generated by the surface separation could be dissipated into the earth, e.g. through the steel construction of the hoist. Conversely, the pulley could also ground the rope.

However, if there is no possibility of grounding the pulley, such as in the case of a crane in the bottom block with a load hook, the load created by the surface separation cannot be diverted. As a result, during operation, electrical charge accumulates in the rope, in the rope pulley, in the bottom block and in the load hook due to the continuous separation of the rope surface from the rope pulley surface. The discharge then occurs unplanned when the rope, rope pulley, bottom block or load hook comes into contact with an external conductor to earth, e.g. if a person or object comes into contact with this component. Electrical discharge can cause electrostatic shock or shock to persons resulting in personal injury, cause fire and/or industrial explosions, and/or cause damage to sensitive electronic equipment.

For humans, an electrostatic charge becomes noticeable from around 3 kV and often leads to a moment of shock, which is associated with the risk of an accident. The type and amount of charge accumulated depends on the material pairing of both components Component surfaces of both components, the number of surface separations and all parameters that influence charge migration, in particular the ambient temperature, the component temperature and the air and surface humidity.

If the use of electrically non-conductive materials (components with ohmic resistance > 10 ⁶ ohms are considered as such) is necessary for the components for design reasons, as is usually the case with the fiber ropes mentioned, then the electrical charge generated during operation must must therefore be derived from at least one of the two components in order to avoid the hazards stated above.

For fiber ropes is from the revelations WO2012042576A1 and JPH01207483A known to provide ropes with antistatic properties. However, short antistatic fibers are used in the form of electrically conductive staple fibers that are spun into a yarn. According to the WO2012042576A1 The conductive staple fibers should be made as short as possible so that a so-called corona discharge can take place. The ends of the staple fibers would act as electrodes to achieve the corona discharge. According to this principle, the greater the number of ends of staple fibers, the better the corona discharge would be. That in the WO2012042576A1 However, the rope described is not suitable for many applications, on the one hand because the staple fibers can easily come out of the yarn and the rope is therefore not suitable for longer periods of use. Furthermore, the yarns specially made with staple fibers are too thick to be used in rope sheath constructions without changing the rope construction.

From the field of application of flat textiles, ie not ropes, it is known to use an antistatic fiber which comprises a multilobal, conductive fiber core which is covered by a non-conductive plastic sheath. Such fibers are from the US 5,202,185 known and are offered, for example, under the brand Nega-Stat ^® P190 and arranged in a grid shape in flat woven, knitted or nonwoven fabrics, for example to produce protective equipment. The US 5,202,185 further teaches that some of these fibers can be used as staple fibers. However, antistatic fibers can also include a fiber core that is not multilobal but, for example, circular, as in writing US 3,803,453 A is described.

It is the object of the invention to provide an antistatic core-sheath rope made of textile fiber material that overcomes the disadvantages of the prior art.

This object is achieved by a rope made of textile fiber material, comprising a rope core and a sheath surrounding the rope core, the rope comprising at least one antistatic multifilament yarn or an antistatic monofilament which is in the rope core, in the sheath, in a between the rope core and the sheath located intermediate sheath and / or in a reinforcement located between the rope core and the sheath, the antistatic monofilament or individual filaments of the antistatic multifilament yarn each comprising a conductive fiber core which is covered by a non-conductive plastic sheath.

According to the invention, at least one antistatic multifilament yarn or at least one antistatic monofilament is arranged in the rope in order to give it the antistatic properties. In contrast to the prior art, no staple fibers are used, but rather a monofilament or multifilament yarn, i.e. a continuous fiber or a continuous fiber yarn, which can be provided parallel to or at an angle to the longitudinal axis of the rope. Since such a multifilament yarn or a monofilament is significantly thinner than a yarn made from antistatic staple fibers, the multifilament yarn or the monofilament can be used more flexibly. Another advantage over staple fibers is that the multifilament yarns or monofilaments cannot be removed from the rope due to their length, meaning that they have a longer service life. This means that antistatic ropes can now also be produced for areas of application where thicker yarns with staple fibers cannot be used.

As is known, the antistatic monofilament or the antistatic multifilament yarn consisting of individual filaments with a conductive fiber core has the property that it attracts the electric field from the surface and can neutralize the entire free charge on the surface of the rope through corona discharge. In other words, the surface charges are attracted to the rope and released into the environment over time through air ionization. This allows the surface discharge of the rope and the rope pulley to be reduced to an area that is safe for people and the environment. As proof of the effectiveness of this, the US 5,202,185 , the US 3,803,453 A and the fiber sold by Barnet under the trademark Nega-Stat ^® P190.

In simple cases, the fiber core of the antistatic monofilament or the fiber core of the individual filaments of the antistatic multifilament yarn can have a circular shape in cross section, such as from the US 3,803,453 A is known. However, it is preferred that the fiber core of the antistatic monofilament or the fiber core of the individual filaments of the antistatic multifilament yarn has a multilobal shape in cross section, as shown in the US 5,202,185 is known because these antistatic fibers have a better antistatic effect. In general, it is preferred if the fiber core of the antistatic monofilament or the fiber core of the individual filaments of the antistatic multifilament yarn is non-metallic. Further preferably, the fiber core comprises electrically conductive carbon black, also called conductivity carbon black. The antistatic multifilament yarns and/or the antistatic monofilaments preferably have a titer of a maximum of 500 dtex.

The antistatic multifilament yarns or the antistatic monofilaments also have the particular advantage that they can be specifically incorporated into the components of the core-sheath rope, possibly only into the sheath, only into the rope core, only into the intermediate sheath or only into the reinforcement. This allows the amount of antistatic fibers to be reduced, which reduces costs and also saves weight.

Particularly preferred is the sheathing and/or the intermediate sheath and/or the reinforcement, i.e. at least one of these components, a braid with braids running in the S direction and in the Z direction, with at least one braid running in the S direction having at least a first antistatic Multifilament yarn or at least a first antistatic monofilament and at least one braid running in the Z direction comprises at least a second antistatic multifilament yarn or a second antistatic monofilament. The antistatic multifilament yarns or the antistatic monofilaments run essentially parallel to the respective braid, apart from a twist caused by optional twisting, and thereby form a cylindrical grid. Such an arrangement enables a particularly uniform arrangement of the antistatic multifilament yarns or the antistatic monofilaments on or under the rope surface, so that electrostatic charges can be absorbed particularly effectively by the fibers and released into the air.

In a further embodiment, the sheathing and/or the intermediate sheath and/or the reinforcement is a braid with braids running in the S direction and in the Z direction, with one or more antistatic multifilament yarns or antistatic monofilaments either only in one or more in the S direction. Directional lichens or only in one or more lichens running in the Z direction. This allows the amount of antistatic multifilament yarns or antistatic monofilaments to be reduced. In one case, only a single antistatic multifilament yarn or a single antistatic monofilament can be used in the rope present. The at least one antistatic multifilament yarn or the at least one antistatic monofilament thereby runs essentially spirally around the direction of the rope on or below the rope surface and runs at essentially equal distances around the rope.

In order to further reduce the amount of antistatic multifilament yarns or antistatic monofilaments, these can only be used in some of the braids running in the S-direction and / or Z-direction, for example only in every second, every third or every fourth in the S-direction and / or Z-direction running braid can be arranged. This means that the structure explained above can still be achieved, with larger grid spacing being achieved.

In the case of braids that include braids with at least two threads or plied yarns running essentially parallel to one another (which can be achieved, for example, if the threads or yarns are wound side by side on a bobbin of a circular braiding machine), the amount of antistatic multifilament yarns or antistatic monofilaments can be further specifically selected if only some, preferably only one, of these threads or yarns of a lichen comprises at least one antistatic multifilament yarn or at least one antistatic monofilament. The other threads or yarns can therefore be free of antistatic multifilament yarns and antistatic monofilaments.

Through the measures mentioned, the proportion of antistatic multifilament yarns or the proportion of antistatic monofilaments in the total titer of the sheath or the intermediate sheath can be adjusted. The proportion of the antistatic multifilament yarns or antistatic monofilaments in the total titer of the sheath or the intermediate sheath is preferably a maximum of 25%, a maximum of 10% or a maximum of 5%. Further preferably, the proportion of antistatic multifilament yarns or the proportion of antistatic monofilaments in the total titer of the sheath or intermediate sheath is at least 0.5%, at least 1%, at least 1.4%, at least 2.1% or at least 3% or essentially 1 .4%, substantially 2.1% or substantially 3%. The titer or total titer is calculated as mass/length and has the unit dtex if the mass is used in grams and the length in 10,000 meters. Tests have shown that these proportions are sufficient even for ropes with long service lives to achieve an excellent antistatic effect over their entire service life. In the case of reinforcement, the proportion of antistatic multifilament yarns or the proportion of antistatic monofilaments in the total titer of the reinforcement can be up to 100%, since the Reinforcement is not designed to cover. In the rope core, the proportion of antistatic multifilament yarns or the proportion of antistatic monofilaments can be freely selected, depending on the antistatic effect to be achieved and the desired mechanical properties of the rope core.

Regardless of whether the antistatic multifilament yarns or antistatic monofilaments are present in the rope core, in the sheathing, in the intermediate sheath or in the reinforcement, it is preferred if the proportion of antistatic multifilament yarns or antistatic monofilaments in the rope is selected such that the rope is electrostatically charged of 8 kV, preferably 5 kV, particularly preferably 3 kV, particularly preferably 2 kV, is not exceeded after an electrostatic charging process, measured at a temperature between 15 ° C and 25 ° C, at a relative humidity between 30% and 40% a distance of 10 cm from the rope. The measurement of the electrostatic charge can be carried out, for example, 10 seconds after an electrostatic charging process. The electrostatic charging process can, for example, be one or more lifting processes or other friction on the rope. The electrostatic charging process can, for example, be carried out until a maximum electrostatic charge is achieved. The stated electrostatic charge of the rope should not be exceeded at least immediately after the rope has been manufactured, but preferably also after a predetermined amount of wear on the rope, particularly preferably at the end of the rope's service life according to Chapter. 6.3.3. (multilayer spooling performance) of ISO TS 23624:2021.

The concrete determination of the stated proportion can easily be carried out by a specialist based on this data. First, the rope is provided and electrostatically charged, for example by a predetermined number of lifting and lowering cycles without a payload, for example after one or five lifting and lowering cycles without a payload. Should the electrostatic charge on the rope exceed the stated electrostatic charge, the proportion of antistatic multifilament yarns or antistatic monofilaments in the rope is increased until the stated electrostatic charge is not exceeded. If it is to be achieved that the mentioned electrostatic charge of the rope also remains at the end of the rope's service life according to Chapter. 6.3.3. ISO TS 23624:2021 or after a predetermined wear relative to this service life (e.g. at 75% of the service life) should not be exceeded, the predetermined wear is first brought about and then the electrostatic charge is determined after an electrostatic charging process. It is advisable to charge the rope electrostatically using the same method that causes wear, for example according to the method mentioned Norm, although preferably no payload is used to create the electrostatic charge.

Alternatively or in addition to antistatic multifilament yarns or antistatic monofilaments in the sheath, these can also be present in the rope core itself. If this comprises several core layers, which can be the case in particular with cores twisted in multiple layers, the at least one antistatic multifilament yarn or the at least one antistatic monofilament is preferably only arranged in the outermost core layer, since this is arranged closest to the rope surface, where the electrostatic Charging occurs when surfaces separate. However, in other cases the rope core could also be braided.

If the at least one antistatic multifilament yarn or the at least one antistatic monofilament is to be arranged in the reinforcement, it can be provided that the reinforcement is made exclusively from antistatic multifilament yarns or antistatic monofilaments. The reinforcement can be designed as standing threads or alternatively as a non-covering braid to form a lattice-shaped network.

In order to achieve the most uniform distribution of antistatic multifilament yarns or antistatic monofilaments on or under the rope surface, the antistatic multifilament yarns or antistatic monofilaments preferably form a uniform cylindrical grid, the mesh size of which is preferably between 5 mm and 20 mm, particularly preferably essentially 10 mm, amounts. In other cases, a non-uniform cylindrical grid could also be provided, for example when antistatic multifilament yarns or antistatic monofilaments are arranged with different spacings in the S-direction and in the Z-direction. If antistatic multifilament yarns or antistatic monofilaments are only present in braids in the S-direction or in the Z-direction, there will usually be no grid but a spiral cover.

As a rule, the at least one antistatic multifilament yarn comprises at least six individual filaments, preferably exactly twenty-four individual filaments. Such multifilament yarns are already available on the market, so no further modifications need to be made.

Since the antistatic multifilament yarns or the antistatic monofilaments are often too thin to be used as a separate yarn on a bobbin of a round braiding machine, the antistatic multifilament yarns and / or the antistatic Monofilaments are twisted with a thread or yarn made of another material, said other material preferably being UHMWPE or PES. This is particularly advantageous because the antistatic multifilament yarns or the antistatic monofilaments can be twisted directly with the "actual" material of the sheath or the rope core without having to take further measures to process the antistatic multifilament yarns or the antistatic monofilaments.

In a preferred embodiment, the rope core comprises high-strength fibers, preferably p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers. Ropes with such rope cores can be used in particular for rope cranes.

Further preferably, the sheathing and/or the intermediate sheath and/or the reinforcement comprises both high-strength fibers, preferably p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers, as well as non-high-strength fibers, preferably PA Fibers, PES fibers or PP fibers, preferably at least a first antistatic multifilament yarn or a first antistatic monofilament being twisted with the high-strength fibers to form a first thread and at least a second antistatic multifilament yarn or a second antistatic monofilament with the non-high-strength fibers is twisted with a second thread. Such a casing is particularly suitable for use in cable cranes.

The rope described above is particularly suitable for use as a crane rope, with the crane rope preferably carrying a bottom block with load hooks for transporting, lifting and lowering loads. As already explained at the beginning, such constructions are particularly prone to electrostatic charging, since the lower block cannot be grounded without further measures. However, the use according to the invention enables the electrostatic charge to be reduced to a harmless level, preferably below the human perception limit of 3 kV.

• Figur 1 zeigt eine Unterflasche eines Krans mit Lasthaken, bei dem ein erfindungsgemäßes antistatisches Seil zum Einsatz kommt.
• Figur 2 zeigt einen schematischen Querschnitt des erfindungsgemäßen Seils.
• Figur 3 zeigt eine schematische Seitenansicht des Mantels des erfindungsgemäßen Seils.

Advantageous and non-limiting embodiments of the invention are explained in more detail below with reference to the drawings.

• Figure 1 shows a lower block of a crane with a load hook, in which an antistatic rope according to the invention is used.
• Figure 2 shows a schematic cross section of the rope according to the invention.
• Figure 3 shows a schematic side view of the jacket of the rope according to the invention.

Figure 1 shows a lower block 1 with load hook 2 of a crane, not shown. In the embodiment shown, the lower block 1 is supported by a 5-fold reeved rope 3 (10-strand reeving), each of which is deflected around a pulley 4 of the lower block 1. In other embodiments, however, the lower block 1 could also be supported by a single-reeved rope 3 (2-strand reeving), in which case the lower block 1 will also only comprise one sheave 4.

The rope 3 according to the invention is a fiber rope, ie a rope 3 made of textile fiber material with a usually essentially non-conductive rope surface. “Non-conductive” is understood here to mean an ohmic resistance of > 10 ⁶ ohms. That section of the rope 3 that comes into contact with the respective pulley 4 is therefore effectively not grounded. Out of Figure 1 It can be seen that the pulley 4 or the lower block 2 is not grounded either, as it hangs freely in the air. If the rope according to the prior art were used as a pure fiber rope without further precautions to reduce the antistatic effect, the rope 3 and the rope 3 would become electrostatically charged during operation of the rope crane due to the up and down movement of the lower block 1 on the rope 3 Bottom bottle 1 come. In order to prevent electrostatic charging, the rope 3 has at least one antistatic multifilament yarn 5 or one antistatic monofilament, as explained in detail below.

At this point, however, it should be emphasized that the rope 3 described here is not intended for applications such as in Figure 1 shown is limited and does not have to be a crane rope. In general, the rope 3 can be used for all applications in which electrostatic charging is to be reduced. The ropes 3 according to the invention usually have an outer diameter of 5 mm to 60 mm.

The structure of the rope 3 according to the invention is in one variant Figure 2 shown, which represents a cross section of a rope 3. The rope 3 includes a rope core 6 and a sheath 7 surrounding the rope core 6. The rope 3 is made of a textile fiber material, that is, both the rope core 6 and the sheath 7 are made of textile fiber material. The rope 3 is preferably made metal-free, possibly apart from optional connecting elements or clamps which are attached to the ends of the rope 3 or at another point on the rope 3, or optionally functional, electrically conductive wires guided in the rope 3, for example as current conductors , information conductor or sensor serve.

Optionally, the rope 3 can have an intermediate sheath 8, which is provided between the rope core 6 and the sheath 7. Depending on the embodiment, this intermediate jacket 8 can also be made of textile fiber material and can preferably be metal-free. Alternatively or in addition to the intermediate jacket 8, a textile, preferably metal-free reinforcement (not shown) can also be used, which is understood to mean a non-covering component such as a net or standing threads. If the reinforcement is used in combination with a covering intermediate sheath 8, the reinforcement can be located either between the rope core 6 and the intermediate sheath 8 or between the intermediate sheath 8 and the sheath 7.

How out Figure 2 It can also be seen that the rope core 6 has several core layers 9, 10, 11, with the core layer that is arranged closest to the sheath 7 being referred to as the outermost core layer 11. In practice, a multi-layer rope core 6 can be produced, for example, if the rope core 6 is produced by multi-layer stranding of strands. In the embodiment shown, the rope core 6 comprises three core layers 9, 10, 11, whereby only two or more than three core layers are used and the individual strand layers can have different lay directions around the longitudinal axis. In other variants, however, the rope core 6 could also be designed without core layers or be formed by several strands that do not form any layers, or be braided.

In order to reduce electrostatic charging of the rope 3 during operation of the rope 3, the rope 3 comprises at least one antistatic multifilament yarn 5 or at least one antistatic monofilament. The antistatic multifilament yarn 5 or the antistatic monofilament or the antistatic multifilament yarns 5 or the antistatic monofilaments is or are present as continuous fibers over essentially the entire length of the rope 3. In technical terms, filament or continuous fiber refers to fibers with a length of > 1000 mm. If necessary, after use there may be breakage points in one or more antistatic filaments, whereby these damaged antistatic filaments can further be referred to as continuous fibers. Multifilament yarns consist of a defined number of individual filaments and are only available in this form and not separated into the individual filaments. Monofilaments are individual filaments of generally greater thickness that are available in this isolated form.

The antistatic multifilament yarn 5 consists of several individual filaments 12, which run essentially parallel and directly next to one another in order to form the respective antistatic multifilament yarn 5. The individual filaments 12 are usually present next to each other loosely and not dispersed in a matrix. The antistatic effect of the antistatic multifilament yarn 5 is due to the special structure of the individual filaments 12, each of which includes a conductive fiber core 13 which is covered by a non-conductive plastic sheath 14. Likewise, the antistatic effect of the antistatic monofilament is due to its special structure, which in turn comprises a conductive fiber core which is covered by a non-conductive plastic cover. The structure described below with fiber core and plastic cover can be used both for the individual filaments 12 of the antistatic multifilament yarn 5 and for the antistatic monofilament.

The preferred structure of the individual filaments 12 or the monofilament is in the US 5,202,185 described, the content of which is hereby incorporated into this application. However, the individual filaments 12 or the monofilament could also be as in the US 3,803,453 A described, the content of which is hereby also incorporated into this application.

The non-conductive plastic sheath 14 of the individual filaments 12 or the monofilament is preferably an extrudable, synthetic, thermoplastic, fiber-forming polymer or copolymer. These include, among others, polyolefins such as polyethylene and polypropylene, polyacrylics, polyamides and polyesters with fiber-forming molecular weight. Particularly suitable shell polymers are polyhexamethylene adipamide, polycaprolactam and polyethylene terephthalate. In general, however, other materials could also be used.

The fiber core 13 of the individual filaments 12 or the monofilament comprises electrically conductive material (ie with an ohmic resistance <10 ⁶ ohms), preferably non-metallic material. The fiber core 13 particularly preferably comprises electrically conductive carbon black, also called conductivity carbon black, in order to achieve the antistatic effect. In general, however, the fiber core 13 could also include other material that gives the fiber core its electrically conductive property. The electrically conductive material is usually dispersed in a polymeric, thermoplastic matrix. This makes it possible to achieve particularly thin diameters of the individual filaments 12 or the monofilaments, whose manageability (eg flexibility) is comparable to classic textile fibers, which would not be possible, for example, if the fiber core 13 were a solid metal core.

When carbon black is used as an electrically conductive material, carbon black concentrations in the fiber core 13 of 15 to 50 percent can be used. Preferred A concentration of 20 to 35 percent is used as this achieves high conductivity while maintaining a reasonable level of processability. The polymer in the fiber core 13 can also be selected from the same group as that for the cladding, or it can be non-fibre-forming since it is protected by the cladding. In general, other materials could also be used.

The cross-sectional area of the fiber core 13 in the individual filaments 12 or in the monofilament should be sufficient to achieve the desired antistatic effect. The proportion of the fiber core 13 in the single filament fiber 12 or in the monofilament can be, for example, at least 0.3% by volume, preferably at least 0.5% by volume and up to 35% by volume.

The conductive fiber core 13 preferably has a multilobal shape in cross section with usually at least 3, preferably 3 to 6 lobes (lobes). Each lobe preferably has an L/D ratio of 1 to 20, where L is the length of a line extending from the midpoint of the junction between the two lowest points of adjacent valleys on either side of the lobe to the farthest point of that lobe. D is the largest width of the flap, measured normal to L. Alternatively, the conductive fiber core 13 could also have a different shape in cross section, such as a circular or oval shape. In other variants, the cross section could also be I-shaped, triangular or square.

The individual filament fibers 12 that can be used for the present invention have, for example, a titer of 6.5 dtex, so that an antistatic multifilament yarn 5 with 24 individual filament fibers 12 has a titer of 156 dtex. The monofilaments could also have a titer of 156 dtex, although the titer could also be chosen to be significantly smaller or larger.

Since the rope 3 described here is a core-sheath rope, it is possible to specifically incorporate the antistatic multifilament yarn 5 or the antistatic monofilament as a textile sub-element, ie as a yarn and in particular as part of a thread, in one or more of the components of the core-sheath rope, ie in the rope core 6, in the sheath 7, in the intermediate sheath 8 and/or in the reinforcement. At this point it should be emphasized that it is possible for both at least one antistatic multifilament yarn 5 and at least one antistatic monofilament to be present in the rope 3. For example, only antistatic multifilament yarns 5 could be present in the sheath 7 and antistatic monofilaments could be present in the intermediate sheath 8. Alternatively, for example, both antistatic multifilament yarns 5 and antistatic ones could be in the sheath 7 Monofilaments are present. In a further alternative variant, it can be provided that there is no mixing and that either only antistatic multifilament yarns 5 or only antistatic monofilaments are present in the rope 3 to bring about the antistatic effect.

Furthermore, the antistatic multifilament yarn 5 and/or the antistatic monofilament can also be incorporated only in the rope core 6, only in the sheath 7, only in the intermediate sheath 8 and/or only in the reinforcement, without antistatic multifilament yarns 5 or antistatic monofilaments in the other components present. In further variants, there are no antistatic multifilament yarns 5 or antistatic monofilaments in only one, only two or three of the components mentioned.

This has the advantage that excess antistatic multifilament yarn 5 or excess antistatic monofilament can be dispensed with. For example, if there is already a sufficient amount of antistatic multifilament yarn 5 in the intermediate sheath 8 in order to achieve the desired antistatic effect, there is no need to add antistatic multifilament yarn 5 to the rope core 6, so that, for example, there are more high-strength fibers in it with the same weight can. Furthermore, it goes without saying that the antistatic multifilament yarns 5 are more expensive than, for example, PES fibers, so that the reduction of antistatic multifilament yarns 5 represents a cost advantage while maintaining the same effect.

The choice of the amount of antistatic multifilament yarns 5 or antistatic monofilaments in the rope 3 depends on various factors, which will be discussed in more detail below. In the simplest case, however, there is only a single antistatic multifilament yarn 5 or a single antistatic monofilament in the rope 3, which is present as a continuous fiber over the entire length of the rope 3. This can be provided in particular for ropes 3 that are not subject to heavy wear.

However, the amount of antistatic multifilament yarns 5 or antistatic monofilaments in the rope 3 is usually selected in such a way that either at the time of production or after a predetermined wear of the rope 3, for example when the rope 3 has reached its service life (ie it is ready to be discarded) according to Chapter 6.3.3 . According to ISO TS 23624:2021, a certain electrostatic charge is not exceeded after an electrostatic charging process (e.g. to achieve a maximum electrostatic charge on the rope). This electrostatic charge is preferably below the human-perceptible limit. Furthermore, this electrostatic charge can be below 8 kV, preferably below 5 kV or particularly preferably below the human-perceptible limit of 3 kV or below 2 kV, measured at a temperature between 15 ° C and 25 ° C, at a relative humidity between 30% and 40% at a distance of 10 cm to rope 3.

In order to determine in more detail the amount of antistatic multifilament yarns 5 or antistatic monofilaments in the rope 3, the considerations and advantages of arranging antistatic multifilament yarns 5 or antistatic monofilaments in the respective components will be discussed below.

If antistatic multifilament yarns 5 or antistatic monofilaments are provided in the sheath 7, their antistatic effect is best because they will be at least partially present on the outer surface of the rope 3. As a result, the antistatic multifilament yarns 5 or the antistatic monofilaments do not have to discharge through other fiber material.

However, since the use of the rope 3 during operation causes damage to the sheath 7 and thus also to the antistatic multifilament yarns 5 or the antistatic monofilaments, the proportion of antistatic multifilament yarns or antistatic monofilaments 5 on the sheath 7 can also be increased in order to not to exceed a certain electrostatic charge even after a predetermined use.

In order to select the proportion of antistatic multifilament yarns 5 or antistatic monofilaments in the sheath 7, the following measures can be used. Embodiments with antistatic multifilament yarns 5 are explained below, although these can also be implemented with antistatic monofilaments instead of the antistatic multifilament yarns 5. For the explanations below, it is understood that in the braids, twists or yarns in which no antistatic multifilament yarns 5 are present, there are preferably no antistatic monofilaments either.

As in Figure 3 As shown, the casing 7 is usually a braid, so that the casing 7 comprises several braids 15a, 15b, of which half of the braids 15a run in the so-called S direction of the casing 7 and the other half of the braids 15b run in the so-called Z -Direction of the sheath 7. According to the invention it can be provided that one or more antistatic multifilament yarns 5 only in the Braids 15a of the S direction are present, only in the braids 15b of the Z direction or both in braids 15a of the S direction and in braids 15b of the Z direction.

If one or more antistatic multifilament yarns 5 are present in both S-direction braids 15a and Z-direction braids 15b, the antistatic multifilament yarns 5 will form a cylindrical grid. If it is a uniform cylindrical grid, the mesh size M of the grid can preferably be between 5 mm and 20 mm, particularly preferably essentially 10 mm. This solution with a uniform cylindrical grid can be chosen not only for the casing 7, but also for the intermediate casing 8 and/or the reinforcement, if these are designed as a braid, or also the rope core 6, if this is designed as a braided rope core 6.

Further is over Figure 3 It can be seen that not all braids 15a, 15b have antistatic multifilament yarns 5, but only every second braid 15a in the S direction and only every second braid 15b in the Z direction has one or more antistatic multifilament yarns 5. However, it could also be provided that all braids 15a, 15b have one or more antistatic multifilament yarns 5 in the S-direction or Z-direction. Alternatively, it could be provided that only every third, every fourth or every fifth braid 15a, 15b in the S-direction or Z-direction has one or more antistatic multifilament yarns 5. Asymmetrical arrangements are also possible, so that, for example, every second braid 15a in the S direction and every third braid 15b in the Z direction has one or more antistatic multifilament yarns 5. In general, it could be provided that the antistatic multifilament yarns 5 are only provided in some of the braids 15a, 15b running in the S-direction or Z-direction. For example, all of the braids 15a, 15b except for one braid could include antistatic multifilament yarns 5.

Out of Figure 3 It can also be seen that the braids 15a, 15b have several threads 16, in this case three different threads 16 per braid 15a, 15b. In practice, such a sheath 7 is produced with several threads 16 per braid 15a, 15b by providing several threads 16 on the bobbins of a round braiding machine. Depending on the desired structure of the sheath 7, however, it can be provided that the braids 15a, 15b can each comprise only one thread 16, only two threads 16 or more than two threads 16. As an alternative to twisting 16, plied yarns could also be provided. The exemplary embodiments below are all included Twisting is explained, but it goes without saying that plied yarns can also be used as an alternative.

Coming back up Figure 3 It can be seen that not every thread 16 of a braid 15a, 15b comprises an antistatic multifilament yarn 5. In the exemplary embodiment shown, the braids 15a, 15b each comprise three threads 16, only one of which comprises antistatic multifilament yarns 5. In general, however, none or all of the threads 16 of a braid 15a, 15b could comprise an antistatic multifilament yarn 5, or all but one or all but two or only one, only two or only three of the threads of a braid 15a, 15b could (n) comprise an antistatic multifilament yarn 5, depending on the number of twists per braid 15a, 15b. It can be freely chosen whether the thread 16 with antistatic multifilament yarn 5 is arranged in the middle of the threads 16 or at the edge of the braid.

The proportion of antistatic multifilament yarns 5 in the sheath 7 can be further influenced if the proportion of antistatic multifilament yarn 5 in the respective thread 16 is selected. In the simplest case, a thread 16 of a braid 15a, 15b consists only of one or more antistatic multifilament yarns 5, folded or twisted together. From the illustrated embodiment of Figure 3 However, it can be seen that the antistatic multifilament yarn 5 can also be twisted with another yarn or thread in order to specifically select the proportion of antistatic multifilament yarn 5. In particular, one, two, three or more than three antistatic multifilament yarns 5 with one or more twists made of high-strength materials such as p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers or one or more twists made of non- be twisted with high-strength materials such as PA fibers, PES fibers or PP fibers. In practical tests, which are explained in more detail below, for example, two antistatic multifilament yarns 5, each comprising twenty-four individual filaments, were twisted with a thread made of UHMWPE, the denier of the UHMWPE threads being more than ten times greater than the denier of the two antistatic multifilament yarns 5.

Out of Figure 3 It can also be seen that some threads 16 are shown with hatching and some of the threads 16 are shown without hatching. Those threads 16 that are shown with hatching are made, for example, from non-high-strength PES fibers and those threads 16 that are shown without hatching are made, for example, from high-strength UHMWPE fibers. Such a structure is particularly common with crane ropes. It is further evident that antistatic multifilament yarns 5 are twisted with PES twists in one of the braids 15a, 15b and are twisted with UHMWPE twists in one of the other braids 15a, 15b.

In general, it can therefore be provided that the sheath 7 contains both high-strength fibers, preferably p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers, as well as non-high-strength fibers, preferably PA fibers, PES fibers. Fibers or PP fibers, wherein preferably at least a first antistatic multifilament yarn 5 is twisted with the high-strength fibers to form a first thread and at least a second antistatic multifilament yarn 5 is twisted with the non-high-strength fibers to form a second thread. The first and second threads are preferably in different braids 15a, 15b. Even if the casing comprises 7 braids 15a, 15b made of different material, as shown in Figure 3 If this is the case, it could, however, be provided that the antistatic multifilament yarns 5 are only twisted with threads of the same material. For example, the antistatic multifilament yarns 5 could be in the embodiment of Figure 3 can also only be twisted with PES threads. Furthermore, it goes without saying that the sheath 7 can also consist of only threads made of a single material, one, some or all of which are twisted with antistatic multifilament yarns 5. For example, the sheathing 7 can also only comprise PES fibers and the antistatic multifilament yarns 5.

The following explains the structure of a first test rope V1 without antistatic multifilament yarns 5, a second test rope V2 with a first amount of antistatic multifilament yarns 5 and a third test rope V3 with a second amount of antistatic multifilament yarns 5. In the second test rope V2, the proportion of antistatic multifilament yarns 5 in the total titer of the sheath 7 was 1.4%. In the third test rope V2, the proportion of antistatic multifilament yarns 5 in the total titer of the sheath 7 was 2.1%.

All three test ropes V1, V2, V3 had a three-layer twisted rope core 6 with 35 strands with an outer diameter of 18 mm. The rope core 6 did not include any antistatic multifilament yarns 5. All three test ropes V1, V2, V3 also had a sheath 7 with an outer diameter of 21 mm, with sixteen braids 15a arranged in the S direction and sixteen braids 15b in the Z direction. For each of the sixteen braids 15a, 15b, three PES threads were made with 1100 dtex / 4-ply / 150 T/m each and one UHMWPE thread with 3300 dtex / 1-ply / 150 T/m, with this arrangement being repeated four times became.

No antistatic multifilament yarns 5 were twisted into the first test rope V1. In the second test rope V2, antistatic multifilament yarns 5 were twisted twice, i.e. in one of the threads 16 of every second braid (alternating with a PES thread and with a UHMWPE thread) two antistatic multifilament yarns 5 with 156 dtex each were twisted. In the third test rope V3, antistatic multifilament yarns 5 were twisted three times, i.e. three antistatic multifilament yarns 5 with 156 dtex each were twisted into one of the threads 16 of every second braid (alternating with a PES thread and a UHMWPE thread).

For greater clarity, a table of the structure of the three test ropes V1, V2, V3 described above is shown here. V1 V2 V3 Antistatic multifilament yarns ---- Twisted twice Twisted 3 times Number of lichens 32 32 32 16 braids in S direction No lichen with anti-static multifilament yarn Every other braid (i.e. 8 braids) with antistatic multifilament yarn Every other braid (i.e. 8 braids) with antistatic multifilament yarn 3 braids with PES twines; 1 braid with UHMWPE threads (repeated 4 times) 3 braids with PES twines; 1 braid with UHMWPE threads (repeated 4 times) 16 braids in Z direction No lichen with anti-static multifilament yarn Every other braid (i.e. 8 braids) with antistatic multifilament yarn Every other braid (i.e. 8 braids) with antistatic multifilament yarn 3 braids with PES twines; 1 braid with UHMWPE threads (repeated 4 times) 3 braids with PES twines; 1 braid with UHMWPE threads (repeated 4 times) Threads without antistatic UHMWPE: 3300 dtex / 1x / 150T/m UHMWPE: 3300 dtex / 1x / 150T/m UHMWPE: 3300 dtex / 1x / 150T/m Multifilament yarns PES: 1100 dtex / 4-fold / 150 T/m PES: 1100 dtex / 4-fold / 150 T/m PES: 1100 dtex / 4-fold / 150 T/m Thread with antistatic --- UHMWPE 3300 dtex / 1-fold + ESD UHMWPE 3300 dtex / 1-fold + ESD 156 dtex / 3-fold / 150 T/m or Multifilament yarn 156 dtex / 2-fold / 150 T/m or PES 1100 dtex / 4-fold + ESD 156 dtex / 3-fold / 150 T/m PES 1100 dtex / 4-fold + ESD 156 dtex / 2-fold / 150 T/m distribution 3 threads per 3 threads per 3 threads per braid: lichen, always without antistatic Lichen: 3 threads without antistatic 3 threads without antistatic Multifilament yarn Multifilament yarn or Multifilament yarn or 2 threads without antistatic 2 threads without antistatic Multifilament yarn + 1 Thread with antistatic Multifilament yarn + 1 thread with antistatic multifilament yarn Multifilament yarn

All three test ropes V1, V2, V3 were tested to determine their antistatic effect after different wear times. Since it is particularly relevant whether the test ropes V1, V2, V3 also have a sufficient antistatic effect at the end of their service life, the antistatic effect was determined after 800 full load cycles, 1200 full load cycles and 1600 full load cycles, corresponding to an equivalent crane use of 4 years, 6 years or 8 years, whereby the service life of the test ropes V1, V2, V3 is 8 years, determined according to Chapter 6.3.3. the ISO TS 23624:2021. The measurement results were as follows: % of lifespan V1 V2 V3 After 800 full load cycles 50% > 20 kV 20-70V 45V After 1200 full load cycles 75% > 20 kV 1.1kV 15-100V After 1600 full load cycles 100% > 20 kV 1.3kV 1.8kV

The antistatic effect, determined via the potential difference measured in V, was measured at a temperature between 15 ° C and 25 ° C, at a relative humidity between 30% and 40% at a distance of 10 cm from the rope 3. The measuring device had a measuring range that ends at 20 kV. To charge the rope electrostatically, five cycles were carried out without a payload on the ungrounded bottom block with a load hook, whereby these cycles are the same as the full load cycles mentioned for determining the service life in accordance with Chapter 6.3.3. ISO TS 23624:2021 was carried out, i.e. the same or an identical lower block was used to determine the service life and electrostatic charge. This method of inducing and determining electrostatic charging can be used for all embodiments described herein.

From the results it can be seen that both test ropes V2, V3 have a significantly better antistatic effect compared to test rope V1, in which no antistatic multifilament yarns 5 were incorporated. From the comparison of the results of the test ropes V2, V3 it can also be seen that the third test rope V3 has a significantly better antistatic effect at 1200 full load cycles. It is therefore particularly preferred if the proportion of the antistatic multifilament yarns 5 or the proportion of the antistatic monofilaments in the total titer of the sheath 7 is at least 2.1% or essentially 2.1%, in the case of a rope 3 up to a point in time shortly before reaching to achieve an excellent antistatic effect over the service life. If one extrapolates these results, it is further preferred if the proportion of the antistatic multifilament yarns 5 or the proportion of the antistatic monofilaments in the total titer of the sheath 7 is at least 3% or essentially 3%, in the case of a rope 3 with a service life of 8 years to achieve an excellent antistatic effect when the service life is reached.

However, it goes without saying that the invention can also be used for ropes 3 that have significantly shorter service lives or are exposed to less stress in other areas of application. In these cases, the proportion of antistatic multifilament yarns 5 or the proportion of antistatic monofilaments in the total titer of the sheath 7 can also be chosen to be significantly lower than stated above. In general, it is therefore preferred if the proportion of antistatic multifilament yarns 5 or the proportion of antistatic monofilaments in the total titer of the sheath 7 is between 0.1% and 25%, preferably between 0.2% and 10%, particularly preferably between 0.5% and is 5%. In one example, it can also be provided that only a single antistatic multifilament yarn 5 or a single antistatic monofilament is twisted with a single thread 16 of a single braid 15a, 15b or is provided instead of this thread 16, regardless of the specific structure of the sheath 7.

Usually, the intermediate sheath 8 optionally provided between the rope core 6 and the sheath 7 is also a braid and can therefore have a braided structure, as described above for the casing 7. It can therefore be provided that - instead of or in addition to the antistatic multifilament yarn 5 in the sheath - at least one antistatic multifilament yarn 5 or at least one antistatic monofilament in the structure described above for the sheath 7 (ie the structure of the braid with braiding, twisting and with these twisted antistatic multifilament yarns 5) are provided in the intermediate jacket 8. When choosing the proportion of the antistatic multifilament yarn 5 or the proportion of the antistatic monofilaments in the total titer of the intermediate sheath 8, it should be noted on the one hand that the antistatic multifilament yarns 5 or the antistatic monofilaments must achieve their antistatic effect through the sheath 7, while at the same time reducing wear of the intermediate jacket 8 plays a smaller role due to the protective effect of the jacket 7. In general, however, it is preferred if the proportion of the antistatic multifilament yarns 5 or the proportion of the antistatic monofilaments in the total titer of the intermediate sheath 8 is between 0.1% and 25%, preferably between 0.2% and 10%, particularly preferably between 0.5% and is 5%. In one example, it can also be provided that only a single antistatic multifilament yarn 5 or a single antistatic monofilament can be twisted with a single thread of a single braid of the intermediate jacket 8 or can be provided instead of this thread, regardless of the specific structure of the intermediate jacket 8.

If one or more antistatic multifilament yarns 5 or antistatic monofilaments are to be present in the reinforcement, the proportion of the antistatic multifilament yarns 5 or the proportion of antistatic monofilaments in the total titer of the reinforcement can also be chosen to be higher than above for the casing 7 or the intermediate casing 8 was described because the reinforcement is designed to be non-covering. In the simplest case, the proportion of the antistatic multifilament yarns 5 or antistatic monofilaments in the total titer of the reinforcement is 100%, i.e. the reinforcement consists only of the antistatic multifilament yarns 5 or antistatic monofilaments. It could also be provided that the reinforcement consists only of high-strength or non-high-strength threads that have been twisted with the antistatic multifilament yarns 5. The reinforcement can be designed as a grid which, for example, has a mesh size of between 5 mm and 20 mm, particularly preferably essentially 10 mm. However, the reinforcement could also be formed by standing threads that lie essentially parallel to the direction of the rope.

However, as mentioned above, one or more antistatic multifilament yarns 5 or antistatic monofilaments could also be present in the rope core 6. If the rope core 6 is designed in multiple layers, such as in Figure 2 shown, is preferred if the at least one antistatic multifilament yarn 5 or the at least one antistatic monofilament is only present in the outermost core layer 11. As a result, the antistatic multifilament yarn 5 or the antistatic monofilament lies as close as possible to the rope surface. This effect can be further enhanced if the casing 7 is chosen to be thin. In the area of application of rope cranes, the rope core 6 is usually made of high strength and therefore preferably consists of p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers, optionally with the addition of the antistatic multifilament yarns 5 or antistatic monofilaments. However, the rope core could also consist of or include non-high-strength fibers.

Claims (15)

Rope (3) made of textile fiber material, comprising a rope core (6) and a sheath (7) surrounding the rope core (6),
characterized in that the rope (3) comprises at least one antistatic multifilament yarn (5) or an antistatic monofilament, which is in the rope core (6), in the sheath (7), in an intermediate sheath (8) located between the rope core (6) and the sheath (7). ) and/or in a reinforcement located between the rope core (6) and the sheathing (7), wherein the antistatic monofilament or individual filaments (12) of the antistatic multifilament yarn (5) each comprise a conductive fiber core (13) which is covered by a non-conductive plastic sheath (14). Rope (3) according to claim 1, wherein the fiber core of the antistatic monofilament or the fiber core (13) of the individual filaments (12) of the antistatic multifilament yarn (5) has a multilobal shape in cross section. Rope (3) according to claim 1 or 2, wherein the sheathing (7) and/or the intermediate sheath (8) and/or the reinforcement is a braid with braids (15a, 15b) running in the S direction and in the Z direction, wherein at least one braid (15a) running in the S direction has at least a first antistatic multifilament yarn (5) or at least a first antistatic monofilament and at least one braid (15b) running in the Z direction has at least a second antistatic multifilament yarn (5) or a second antistatic one Monofilament includes. Rope (3) according to claim 1 or 2, wherein the sheathing (7) and/or the intermediate sheath (8) and/or the reinforcement is a braid with braids (15a, 15b) running in the S direction and in the Z direction, wherein one or more antistatic multifilament yarns (5) or antistatic monofilaments are present either only in one or more braids (15a) running in the S direction or only in one or more braids (15b) running in the Z direction. Rope (3) according to claim 3 or 4, wherein antistatic multifilament yarns (5) or antistatic monofilaments are provided only in some of the braids (15a, 15b) running in the S-direction and / or Z-direction, preferably only in every second one third or every fourth lichen (15a, 15b) running in the S-direction and / or Z-direction. Rope (3) according to one of claims 3 to 5, wherein those braids (15a, 15b), which comprise at least one antistatic multifilament yarn (5) or at least one antistatic monofilament, comprise at least two threads (16) or plied yarns, of which only some, preferably only one or one, comprises at least one antistatic multifilament yarn (5) or at least one antistatic monofilament. Rope (3) according to one of claims 1 to 6, wherein the proportion of the antistatic multifilament yarns (5) or the proportion of the antistatic monofilaments in the total titer of the sheath (7) or the intermediate sheath (8) is a maximum of 25%, a maximum of 10% or a maximum of 5 % amounts. Rope (3) according to one of claims 1 to 7, wherein the proportion of the antistatic multifilament yarns (5) or the proportion of the antistatic monofilaments in the total titer of the sheath (7) or the intermediate sheath (8) is at least 0.5%, at least 1%, is at least 1.4%, at least 2.1% or at least 3%. Rope (3) according to one of claims 1 to 8, wherein the proportion of antistatic multifilament yarns (5) or antistatic monofilaments in the rope (3) is selected such that an electrostatic charge on the rope (3) of 8 kV, preferably 5 kV, particularly preferably 3 kV, particularly preferably 2 kV, is not exceeded after an electrostatic charging process, measured at a temperature between 15 ° C and 25 ° C, at a relative humidity between 30% and 40% at a distance of 10 cm from the rope ( 3). Rope (3) according to one of claims 1 to 9, wherein the rope core (6) comprises a plurality of core layers (9, 10, 11) and the at least one antistatic multifilament yarn (5) or antistatic monofilament in the rope core (6) only in the outermost core layer (11) is arranged. Rope (3) according to one of claims 1 to 10, wherein the reinforcement is made exclusively from antistatic multifilament yarns (5) or antistatic monofilaments, and the antistatic multifilament yarns (5) or antistatic monofilaments are preferably standing threads. Rope (3) according to one of claims 1 to 10, wherein the antistatic multifilament yarns (5) or antistatic monofilaments form a uniform cylindrical grid, the mesh size (M) of which is preferably between 5 mm and 20 mm, particularly preferably essentially 10 mm. Rope (3) according to one of claims 1 to 12, wherein the at least one antistatic multifilament yarn (5) or antistatic monofilament is twisted with a thread (16) or yarn made of another material, said other material preferably being UHMWPE or PES. Rope (3) according to one of claims 1 to 13, wherein the rope core (6) comprises high-strength fibers, preferably p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers. Rope (3) according to one of claims 1 to 14, wherein the sheath (7) and / or the intermediate sheath (8) contain both high-strength fibers, preferably p-aramid fibers, m-aramid fibers, LCP fibers, UHMWPE fibers or PBO fibers , as well as non-high-strength fibers, preferably PA fibers, PES fibers or PP fibers, preferably at least a first antistatic multifilament yarn (5) or antistatic monofilament being twisted with the high-strength fibers to form a first thread and at least a second antistatic multifilament yarn (5) or antistatic monofilament is twisted with the non-high-strength fibers to form a second thread.

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