Paper guide rope

Abstract

The invention relates to a paper guide rope braided from a plurality of textile subunits, wherein each subunit contains a plurality of twisted yarns made from multifilament yarn. The rope according to the invention is characterized in that the titre of at least part of the twisted yarns, preferably of all the twisted yarns, is in each case at most 5000 dtex, and that the twist rate of at least part of the twisted yarns, preferably of all the twisted yarns, is in each case at least 150 T/m.

Claims

1. A paper guide rope braided from a plurality of textile subunits, wherein each subunit contains a plurality of twisted yarns made from multifilament yarn, characterized in that the titre of each yarn in at least part of the twisted yarns is at most 5000 dtex, and that the twist rate of each yarn in at least part of the twisted yarns is 200 T/m.

2. A paper guide rope according to claim 1, characterized in that the rope, the subunits and the twisted yarns have no reinforcement.

3. A paper guide rope according to claim 1, characterized in that the titre of each yarn in the twisted yarns is 400 dtex to 5000 dtex.

4. A paper guide rope according to claim 1, characterized in that the diameter of the rope ranges from 6 to 17 mm.

5. A paper guide rope according to claim 1, characterized in that the textile material of at least part of the twisted yarns consists of polyamide.

6. A paper guide rope according to claim 1, characterized in that the number of twisted yarns per subunit is at least 7.

7. A paper guide rope according to claim 1, wherein the titre of each yarn in all of the twisted yarns is at most 5000 dtex, and the twist rate of each yarn in all of the twisted yarns is at least 150 T/m.

8. A paper guide rope according to claim 1, wherein the twist rate of each yarn in the twisted yarns is 150 T/m to 250 T/m.

9. A paper guide rope according to claim 3, wherein the titre of each yarn in the twisted yarns is 2500 dtex to 4500 dtex.

10. A paper guide rope according to claim 3, wherein the titre of each yarn in the twisted yarns is 4200 dtex.

11. A paper guide rope according to claim 4, wherein the diameter of the rope is 8 to 13 mm.

12. A paper guide rope according to claim 6, wherein the number of twisted yarns per subunit is 9 to 16.

13. A paper guide rope braided from a plurality of textile subunits, wherein each subunit contains a plurality of twisted yarns made from multifilament yarn, characterized in that the titre of each yarn in at least part of the twisted yarns is at most 5000 dtex, and that the twist rate of each yarn in at least part of the twisted yarns is at least 200 T/m.

14. A paper guide rope according to claim 13, characterized in that the twist rate of each yarn in the twisted yarns is 200 T/m to 350 T/m.

Description

SHORT DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows an embodiment of a braided paper guide rope.

(2) FIG. 2 shows a further embodiment of a braided paper guide rope.

DETAILED DESCRIPTION OF THE INVENTION

(3) It has been found that paper guide ropes the textile subunits of which are not made up of thick twisted yarns (having a thickness of, e.g., 8400 dtex per twisted yarn) with a relatively low twist rate (typically about 80 T/m), but of relatively thin twisted yarns with a very high twist rate, exhibit excellent properties in terms of abrasion resistance, with the elongation properties being good at the same time.

(4) With the rope according to the invention, there is no necessity in particular to provide an additional reinforcement so that, according to a preferred embodiment of the present invention, neither the rope nor the subunits or their twisted yams, respectively, comprise a reinforcement.

(5) The twist rate of the twisted yarns in the rope according to the invention may in each case be 150 T/m to 350 T/m, preferably 150 T/m to 250 T/m, particularly preferably 200 T/m.

(6) The titre of the twisted yarns in the rope according to the invention may in each case be 400 dtex to 5000 dtex, preferably 2500 dtex to 4500 dtex, particularly preferably 4200 dtex.

(7) Any suitable textile multifilament yarn may be used as a fibre material for manufacturing the twisted yarns. In particular, at least part of the twisted yarns may consist of polyamide multifilament yarn. However, yarn mixtures may also be provided. For example, a twisted yarn with 3 strands can be composed of one yarn of polyamide and two yarns of a different material, for example, polyester.

(8) Optionally, the multifilament yarns and, respectively, the twisted yarns produced therefrom can be impregnated and/or thermoset in a manner known per se. Also the entire rope can be impregnated and/or thermoset in a manner known per se.

(9) The number of twisted yarns per subunit is preferably at least 7, particularly preferably 9 to 16.

(10) For the purposes of the present invention, the term subunit is understood to mean accumulations of fibre material which end up lying in parallel and next to each other in the rope, such as, e.g., a plurality of twisted yarns lying next to each other, twisted yarns which have been braided or twisted yarns which have been twisted around each other.

(11) In order to demonstrate the term subunit, FIGS. 1 and 2 show two different embodiments of a paper guide rope 1.

(12) In the embodiment according to FIG. 1, the rope 1 is composed of subunits 2 (herein: braided rhombi) which, in each case, contain more than seven twisted yarns 3. Said subunits 2 can be produced, in each case, by means of two bobbins operating one after the other, with the shape of a braided rhombus resulting therefrom (framed in FIG. 1). In the subunits, the twisted yarns lie essentially in parallel next to each other.

(13) In the embodiment according to FIG. 2, the rope 1 is likewise composed of subunits 2, which, in each case, are produced by means of two bobbins. The result is, in each case, two elements 2, 2 (framed in FIG. 2), which lie next to each other at least partly. The subunit 2 made up of the sections lying next to each other of the two elements 2, 2 again comprises at least seven twisted yarns. Also in this embodiment, the twisted yarns lie essentially next to each other in the subunits 2 or in their elements 2, 2, respectively.

(14) Correspondingly, this definition of the subunit is applicable also to embodiments which are formed by more than two bobbins operating one after the other in the two machine directions S and Z. However, today, such a rope structure is not intended for current braiding machines.

(15) The paper guide rope according to the invention may be provided in the form of a hollow rope or also in the form of a rope with a core.

EXAMPLES

(16) The following four ropes were produced:

(17) 1) A rope according to the invention:

(18) A twisted yarn made of PA6 multifilament: 1400 dtex x3 200T/m (in S-direction and Z-direction, respectively)

(19) This twisted yarn is impregnated.

(20) Construction of the rope: braided on a braiding machine with 16 bobbins with the following equipment: S-direction: 8 bobbins, each with 5 S-twisted yarns Z-direction: 4 bobbins, each with 5 Z-twisted yarns, and 4 bobbins, each with 4 Z-twisted yarns

(21) Hence, the subunit in the S-direction consists of 10 twisted yarns.

(22) Hence, the subunit in the Z-direction consists of 9 twisted yarns.

(23) 2) A paper guide rope of conventional design with a reduced twist rate of the twisted yarn:

(24) A twisted yarn made of PA6 multifilament: 1400 dtex x6 20T/m (in S-direction and Z-direction, respectively)

(25) This twisted yarn is impregnated.

(26) Construction of the rope: braided on a braiding machine with 16 bobbins with the following equipment: S-direction: 8 bobbins, each with 2 S-twisted yarns Z-direction: 6 bobbins, each with 3 Z-twisted yarns, and 2 bobbins, each with 2 Z-twisted yarns

(27) 3) A paper guide rope of conventional design (with normal twist rate of the twisted yarn):

(28) A twisted yarn made of PA6 multifilament: 1400 dtex x6 80T/m (in S-direction and Z-direction, respectively)

(29) This twisted yarn is impregnated.

(30) Construction of the rope: braided on a braiding machine with 16 bobbins with the following equipment: S-direction: 8 bobbins, each with 2 S-twisted yarns Z-direction: 4 bobbins, each with 3 Z-twisted yarns, and 4 bobbins, each with 2 Z-twisted yarns

(31) 4) A rope with a monofilament reinforcement

(32) Construction of the rope: braided on a braiding machine with 16 bobbins with the following equipment: S-direction: 8 bobbins, each with 1 S-element Z-direction: 8 bobbins, each with 1 Z-element S-element: 2 S-twisted yarns (PA6 multifilament 1400 dtex x6 80T/m) around which 16 PA-monofilaments (diameter 0.2 mm) have been braided Z-element: 2 Z-twisted yarns (PA6 multifilament 1400 dtex x6 80T/m) around which 16 PA-monofilaments (diameter 0.2 mm) have been braided
Measuring method of dry elongation:

(33) At a load of 1 kg, 1 m of rope is marked. Then, a load of 80 kg is applied, the load is kept for 5 min, and subsequently the elongation is read off. Elongation in cm =elongation in %

(34) Measuring method of wet elongation:

(35) Similar to dry elongation, but after the marking of lm of rope, the rope is placed for 5 min in water, which is cold at 25 C.

(36) The elongation values measured in the above ropes 1) to 4) are illustrated in the following table:

(37) TABLE-US-00001 Dry elongation Wet elongation % % Rope 1) (according to the invention) 2.4 4.4 Rope 2) 1.8 3.5 Rope 3) 1.9 3.5 Rope 4) 2.8 4.5
Data regarding lifetime and abrasion resistance:

(38) The measure of the lifetime is the residual breaking load in [%] after a simulated run in a wet section of a paper-making machine. For this purpose, a test unit consisting of 10 pulleys was developed. The rope circulates with 800 m/min and is thereby sprayed with water (consumption: 1.6 l/h). The rope is operated at a tension of 30 kg, and, for achieving an additional abrasion effect, some of the rope pulleys are not alignedi.e., the rope runs slightly over the rope pulley flank.

(39) The residual strength of the ropes 1) to 4) after 24 h of this experiment is indicated in the following table:

(40) TABLE-US-00002 24 h residual strength % Rope 1) (according to the invention) 56.7 Rope 2) 24.3 Rope 3) 49.2 Rope 4) 39.5

(41) It is clearly evident that the rope according to the invention exhibits an improved residual strength, with the elongation properties being satisfactory at the same time. An optical assessment of the rope indicates a satisfactory appearance, while, for example, rope 3 shows clearly visible stress marks.