JPH01104890A - Non-metallic end stopping method of polyoxymethylene rope - Google Patents

Abstract

PURPOSE: To provide a method for carrying out the nonmetallic fastening of the end of a polyoxymethylene rope by which the difference of tensile strengths is reduced by carrying out resin embedding and fixing molding in a specific FRP socket to form a fastened part of the end. CONSTITUTION: This method for carrying out the nonmetallic fastening of the end of a rope 3 obtained by twisting polyoxymethylene superdrawn filaments having high strength and high modulus, in a nonmetallic FRP socket 1 comprises forming the fastening part of the end by carrying out resin embedding and fixing molding in the high strength socket 1 having a entrance part at the side of the rope having nearly the same diameter as that of the rope 3, and a part having an inner diameter larger than the diameter of the diameter of the rope 3 and no eccentricity, to provide the objective fastened part of the end of the rope 3.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for end-stopping a rope made of a polyoxymethylene superstretched filament having high strength and elastic modulus and excellent weather resistance.

<Conventional technology> Conventional μi plates are made of metal such as steel, synthetic resin,
For example, polyamide, polyester, aromatic polyamide, etc. are used alone or in combination as materials. Wire ropes made of metal are compared to synthetic resin ones.
Although it is stronger, it is heavier than metal and rusts.
There are drawbacks such as: Also, gold Jllop is gold 14 @
Due to the electromagnetic induction phenomenon 1), there have been restrictions on its use, especially in fields related to power overhead lines. On the other hand, when synthetic resin is used as a material, the tensile strength is generally lower than that of steel, so it is difficult to obtain high strength. Materials for general synthetic fiber ropes include materials with high tenacity in the glaze, i.e. tensile strength of 6 to 10 by ordinary multi-stage stretching method.
f/d fiber or polyester fiber, or aramid (para-
Phenylentele 7/ruamide) fibers are used. However, in the case of knife or polyester fibers, their specific strength (tensile strength/weight per unit length) is low due to their low tensile strength5.Furthermore, in the case of aramid fibers, their specific strength is Since the fibers are easily damaged by buckling of large objects and do not have good weather resistance, they have the disadvantage of having to be covered with an outer covering (e.g., polyethylene, polyester, thermoplastic nitrogen, etc.). This leads to the disadvantage that the manufacturing cost increases, and even with this method of covering the outer sheath, the phenomenon of single fiber breakage due to buckling cannot be completely eliminated.Furthermore, these fibers generally have a small denier, and it is difficult to separate them from a large number of filaments. Since it needs to be twisted into a rope, it has the disadvantage that the manufacturing process is more complicated than that of metal rope.

In recent years, as a new rope or rope material, Japanese Patent Application Laid-Open No. 60-21989 describes a large diameter plastic material made by dielectrically heating and stretching it to orient and crystallize it to increase its tensile strength and tensile modulus. A plastic rope constructed by twisting and assembling glass material is disclosed.

In addition, as a method for producing ultra-stretched polyoxymethylene filaments, a new production method using a pressure stretching method using a heating medium was also disclosed in Japanese Patent Application Laid-Open No. 6.
It is disclosed in the publication No. 0-183122. High-strength polyoxymethylene has a specific gravity of only about 5.5 times that of steel, making it lightweight and rust-resistant. Another feature of polyoxymethylene superdrawn wires is that, like metals, it is possible to produce superelectrically drawn wires on the order of millimeters, which is different from the wire diameter on the order of microns used for synthetic fiber ropes. Having a wire diameter on the order of millimeters is advantageous in the rope manufacturing process, and the rope can be manufactured through a simpler manufacturing process compared to synthetic fiber ropes.

However, when polyoxymethylene is used as a material for ropes, it is necessary to secure the ends in some way in order to take advantage of the material's high strength properties. For example, if the eye splice method used for conventional metal ropes is used to fix the ends, slipping occurs between the polyoxymethylene superdrawn filaments, so the high strength of the polyoxymethylene material cannot be fully utilized. There are drawbacks that cannot be exploited. Another method for fixing ropes is the socket processing method for metal ropes. This is a method in which an alloy or the like is poured into the end so that it has a fixed cylindrical or conical shape, and then fixed. This method is also common for metal μm plastics, but if this socket method were to be applied to polyoxymethylene, it would be possible to encapsulate the outer cylindrical portion of the socket with an epoxy resin. In this case, the outer cylinder needs to have strength, and for example, a high-strength metal pipe can be considered. When used as a cylindrical T-socket made of other non-metallic materials such as polyethylene/vinyl chloride, when a load is applied to the rope, the socket part will break due to stress, making it impossible to use it as a socket. Can not. Furthermore, in Japanese Patent Application No. 128084/1984, FRP ga
-Pop holders have also been proposed.

<Problems to be Solved by the Invention> When a super-stretched polyoxymethylene filament having high strength and high modulus of elasticity is used for end-stopping with a socket as a rope, the conventional eye splice method or socket processing method Slipping between oxymethylene super-stretched filaments,
Alternatively, peeling occurs at the ends due to peeling between the polyoxymethylene ultra-stretched filament and the resin, and when viewed as a rope, no practical high-strength end-stopping method has been achieved. In other words, it has the disadvantage that the tensile strength after end fixing is small compared to the tensile strength of the material itself.When a metal socket is used for socket processing, although the strength is satisfactory, it is susceptible to rust. It is possible to use a non-metallic material such as vinyl chloride for the outer cylinder, but in this case, the outer cylinder does not have enough tensile strength, so it has the disadvantage of being heavy. It is practically unusable because the outer cylinder part will break.In addition, in the case of the FRP holder proposed in Japanese Patent Application No. 128084/1984, the center of the pop-up and the center of the FRP cylinder should be aligned, and the terminal It is difficult to process, eccentricity inevitably occurs, and p-
When it is pulled as a pulley, it is pulled diagonally, resulting in a decrease in tensile strength and the occurrence of tensile strength loss, which is undesirable.

<Means for Solving the Problems> The present invention provides a method for end-stopping a tube twisted from a high-strength, high-modulus polyoxymethylene super-stretched filament in a non-metallic FRP socket. The rope side entry part of the FRP socket has a straight pipe part having an entrance diameter substantially equal to the rope diameter and an inner diameter larger than the rope diameter, and
This is a non-metallic end-stopping method for a polyoxymethylene loop, which is characterized by forming an end-stop part by embedding and firmly molding resin in a high-strength FRP socket without eccentricity.

The polyoxymethylene used in the method of the present invention is obtained by a known polymerization method using formaldehyde or trioxane as a raw material. Moreover, either a homopolymer or a copolymer obtained by copolymerizing ethylene oxide or the like may be used.

A polyoxymethylene superstretched filament having high strength and high elastic modulus can be obtained by dielectric heating drawing and/or external heating drawing manufacturing technology. For example, the manufacturing technology is
It is disclosed in the publication No.-148616. When the unstretched polyoxymethylene body is changed to a stretching ratio of 8 to 35 times, the tensile strength is 0.5 to 1.7 GPa and the tensile modulus is 1.
It is possible to change it from 0 to 50 GPa. When used as the superstretched filament for rope of the present invention, the tensile modulus is preferably 10 GPa or more. More preferably, the tensile modulus is 20 GPa or more and the tensile strength is 1.3 GPa or more, and if it is less than that, high physical properties cannot be expected as a rope. In addition, the wire diameter of polyoxymethylene is
A length of 10 m or less can be used. The wire diameter can be arbitrarily selected depending on the rope to be manufactured.

Seeds are usually manufactured by twisting together several ultra-stretched filaments. A twisted yarn body is usually formed from 3 to 7 super-drawn filaments. There are usually two types of twist: S twist and 2 twist, and either type can be manufactured. Furthermore, it is also possible to twist a plurality of these twisted μm fibers together. The present invention is characterized in that an end stop portion is formed by embedding a twisted polyoxymethylene super-stretched filament in a resin in a high-strength FRP socket, and then fixing and molding it.

The resin used in the present invention may be any resin as long as it solidifies and maintains a certain shape; for example, thermoplastic resins such as epoxy resin, acrylic resin, polyoxymethylene, and polypropylene are preferred. In the case of a curable resin, the end can be processed by pouring it into a socket, and in the case of a thermoplastic resin, the end can be processed by injection molding. In the case of a thermoplastic resin, it is necessary to select a resin having a melting point approximately equal to or lower than the melting point of polyoxymethylene.

The FRP socket used here is characterized by its structure.

In other words, the socket is not simply cylindrical or conical, but is made of a straight tube having an entrance diameter that is substantially the same as the rope diameter, and FRP that has an inner diameter larger than the rope diameter. It is characterized by the fact that the centers are aligned, that is, there is no eccentricity. The straight pipe section of the eye-side entry portion of the FRP socket has a diameter that is substantially equal to or slightly larger than the rope diameter. The length of the straight pipe portion may be at least the diameter. When processing rope sockets, it is particularly difficult to process the ends while preventing eccentricity between the center of the rope and the center of the FRP socket, but in the case of the FRP socket according to the present invention, Since a straight pipe section is provided, eccentricity can be easily prevented. The FRP socket can be manufactured by the known filament winding method, the drawing method, or the method of forming multiple layers of tubular knitted fabrics of long fibers and curing the next layer with resin.

Examples of the fibers used include high-strength fibers such as glass, carbon, aramid fiber, high-strength polyethylene fiber, and ultra-stretched polyoxymethylene fiber. Further, as the cured resin, epoxy resin, fusible polyester resin, vinyl ester resin, etc. are used.

The effect of rope end processing can be compared to the subsequent variation in rope pull-out stress.

The pull-out stress in the rope is determined by the following method.

That is, as shown in Figure 1, both ends of the polyoxymethylene rope are processed into sockets to form terminal parts, and then a tensile test is conducted to determine the breaking stress (Kg) of the rope or the polyoxymethylene loop. The maximum stress (Kf) immediately before pulling out from the end of the sheet is taken as the pull-out stress, and the standard deviation can be used for evaluation.

<Example> Next, the present invention will be explained in more detail with reference to Examples.

Examples, comparative examples Tensile strength 200 Kf, tensile modulus 40 GPa, outer diameter 1
．． A 12 m rope was manufactured using a super-stretched linear T-material of 1 wa polyoxymethylene homopolymer (Asahi Kasei Corporation Tenatsuku Aoio). The rope had a size of 7×7411, and was used to perform the end-stopping process. The socket is made of FRP cut from epoxy resin filled and reinforced with 70% glass fiber, with an inner diameter of 28mm, a length of 200m, and a socket straight pipe diameter of 13IIJ and a length of 20mm. After inserting and fixing the rope into the socket, use epoxy resin (Ciba).

It was embedded and hardened in Geigy's Acrudite, Ravid). As a comparative example, a pipe with an inner diameter of 28 m, which does not have a straight pipe part,
An FRP socket having the same dimensions of 200 m in length was used and end-stopped using the same method. A tensile test was conducted 72 hours after curing. The results of the tensile test are shown in Table 1. It can be seen that in the examples according to the present invention, the variation in tensile stress is small and the physical properties are stable.

Table 1〈Effects of the Invention〉 What has not yet been invented is a method for twisting a high-strength, high-modulus polyoxymethylene super-drawn filament and terminal processing using the rope, woon, and ket method.9. FRP in which the side entrance part has a straight pipe part whose entrance diameter is substantially the same as the rope diameter, an inner diameter larger than the rope diameter, and which is not eccentric.
By embedding and fixing the rope in resin to form an end stop, it is possible to reduce variations in the tensile stress of the rope compared to the conventional method of simply fixing the rope in resin using a cylindrical socket. .

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the form of the socket processed portion of the sample. 1...FRP socket, 2...straight pipe section, 3...polyoxymethylene rope, 4...resin patent applicant Asahi Kasei Corporation Figure 1

Claims (1)

[Claims] When end-stopping a rope twisted from high-strength, high-modulus polyoxymethylene ultra-stretched filaments in a non-metallic FRP socket, the rope-side entrance of the FRP socket has an entrance diameter that is substantially the same as the rope diameter. A polyoxymethylene rope having a straight pipe part having a straight pipe part and an inner diameter larger than the rope diameter, and having an end stop part formed by embedding and fixing molding in a resin in a high-strength FRP socket without eccentricity. Non-metallic end fixing method.