JP2730859B2 - Molding method for phenolic resin molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a phenolic resin molded article.

[0002]

2. Description of the Related Art Synthetic resins have been used in various fields in place of conventional materials such as metals or cements because of their characteristics such as lightness and strength. Because of its excellent heat resistance and flame retardancy, it has attracted attention in the field of electrical construction materials and the like.

[0003] However, the molding of phenolic resin moldings is
A method is used in which a phenol resin mixed with an appropriate amount of a curing agent is injected into a mold and heated and molded.However, during the curing of the phenol resin, a considerable amount of water and steam moisture and volatile components are generated from the phenol resin. As a result, irregularities called "avatars" are formed on the surface of the molded article after curing due to the moisture and the like, thereby deteriorating the aesthetic appearance and remaining as water remaining inside the molded article, resulting in a deterioration in quality.

[0004] For this reason, conventionally, a step of slightly opening the mold during the formation, a so-called degassing step, is performed an appropriate number of times to remove generated moisture and the like.

[0005]

Since the degassing step is performed an appropriate number of times as described above, the degassing step requires time,
In particular, when molding a long molded product or a molded product having a complicated shape having a large thickness, there is a problem that the time and labor required for the degassing step are increased and the production efficiency is significantly reduced. In addition, in the above-described degassing process, the dimensions of the molded product are likely to be out of order due to the swelling phenomenon associated with the disassembly / assembly and sliding / returning of the mold, resulting in a decrease in the dimensional accuracy of the molded product. Further, when a desired strength is required, a reinforcing bar or the like is disposed inside the molded product, but there has been a problem such as an increase in weight.

[0006] Therefore, despite having many features such as light weight and excellent flame retardancy, the above-mentioned generation of moisture and the like at the time of curing becomes an obstacle, and relatively easy molding of a thin material, Except for molding by drawing, molding with phenolic resin was not performed.

[0007]

According to a first aspect of the present invention, there is provided a method for molding a phenolic resin molded article, wherein a water-conducting member is filled in a predetermined mold with at least a portion thereof formed by the mold. The mold is arranged so as to protrude outward from the space, and a phenol resin is filled in the mold and cured.

According to a second aspect of the present invention, there is provided a method for molding a phenolic resin molded article, wherein a water-conducting member is projected outwardly from a filling space formed at least in part by a mold in a predetermined mold. The mold is filled with a phenol resin, and cured while removing water and the like generated from the phenol resin to the outside of the filling space by the water-conducting member.

[0009]

In a predetermined mold, a water-conducting member is disposed so that at least a part thereof protrudes outward from a filling space formed by the mold, and a phenol resin is filled in the mold, and phenol resin is filled in the mold. By curing while removing water and the like generated from the resin to the outside of the filling space by the water-conducting member, deterioration of the quality of the molded product due to the water and the like generated at the time of curing is prevented. Further, after curing, the water conducting member plays a role of a reinforcing material.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

In this embodiment, a description will be given by taking as an example a case where a utility pole is formed by the method for forming a phenolic resin molded product according to the present invention.

FIG. 1 shows a schematic structure of a utility pole frame formed based on the method for molding a phenolic resin molded product according to the present invention.

In FIG. 1, reference numeral 1 denotes an outer frame having a detachable annular bottom plate 11 at the bottom, which is formed in a hollow frustoconical shape having a thick upper portion and a thinner lower portion. This outer formwork 1
A resin injection pipe 12 connected to a resin injection device (not shown) is connected to a lower portion of the apparatus.

Reference numeral 21 denotes a mandrel main body which is loosely fitted in the outer mold frame 1, and is formed in a hollow frustoconical shape having a thick upper portion and a thinner lower portion, similarly to the outer mold frame 1.

At the upper end of the mandrel main body 21, a hanging metal fitting 22 is provided, and on the outer peripheral surface of the upper end, a crown-shaped upper female metal 25 is mounted.

As shown in FIGS. 1 and 2, the upper female gold 25 is provided on a main body 25a mounted on the upper end of the mandrel main body 21 and is radially spaced from a peripheral surface of the main body 25a at an appropriate interval. Plurality of mandrel holding pieces 23 arranged in
And radially arranged above the mandrel holding piece 23 and above the upper end of the outer mold frame 1 on the peripheral surface of the main body 25a,
And a plurality of upper support members 24 extending slightly longer outward than the mandrel holding pieces 23.

At the lower end of the mandrel body 21,
A frusto-conical mandrel tail 26 is formed, and at the base end of the mandrel tail 26, an annular lower female metal 28 having a large number of lower support members 27 arranged radially is in contact with and detachable from the bottom plate 11. It is inserted in.

Therefore, the mandrel main body 21, the hanging metal fitting 22, the upper female gold 25, the mandrel tail 26, and the lower female gold 2
A mandrel 2 is formed by members such as 8 and a filling space 3 is formed between the outer mold 1 and the mandrel 2.

Here, the inner surface of the outer mold 1 and the outer surface of the mandrel main body 21, that is, the main surface of the mold in contact with the product is:
The outer mold 1 is finished smoothly by hard chrome plating or the like, and is vertically held by a framework (not shown).

Next, a method for molding a phenolic resin molded article according to the present invention using the thus configured mold will be described.

First, the glass roving 4 is stretched and arranged on the outer peripheral surface of the mandrel main body 21.

The glass roving 4 is used not only as a water-conducting member for guiding moisture and the like generated during the curing of the phenol resin described later, but also as a reinforcing material after the curing. It is formed in a string shape.

As shown in FIG. 3, the glass roving 4 is stretched over several layers between a plurality of upper support members 24 and a lower support member 27 arranged above and below the mandrel body 21. , Around the outer surface of the mandrel body 21.

Next, the mandrel 2 on which the above-mentioned glass roving 4 is set is lifted by the hanging metal fittings 22 and inserted into the outer mold frame 1 by a lifting device (not shown). Then, the mandrel tail 26 is guided by the layer of the glass roving 4 and descends, is inserted into the hole of the bottom plate 11 while being guided, and the mandrel 2 is disposed at a predetermined position in the outer mold 1. At this time, the upper part of the mandrel 2 is positioned and held on the upper end of the outer mold frame 1 by the mandrel holding piece 23.

Then, a liquid phenol resin 5 containing an appropriate amount of a curing agent is injected into the filling space 3 from the resin injection tube 12 and is filled up to the upper end surface of the outer mold 1.

After filling the phenolic resin 5 and waiting for a few hours for initial gelling, the heating means (not shown) slowly raises the temperature and holds the phenolic resin. 5 gradually cures from the surface.

At this time, the moisture generated from the phenolic resin 5 and the volatile substances in the curing agent rise inside the glass roving 4 by capillary action, and are guided to the upper end of the glass roving 4 as shown in FIG. It is dropped on the upper surface of the molded product that has started to evaporate or harden and is released to the outside.

After the curing of the phenolic resin 5 is completed, the mandrel main body 21 having the mandrel tail portion 26 is first pushed upward by a hydraulic device (not shown) after natural heat radiation cooling, and subsequently, The molded product is extruded upward together with the bottom plate 11, the lower female gold 28, and the upper female gold 25, and is removed from the outer mold frame 1.

Subsequently, both ends of the molded product are taken along the line XX shown in FIG.
A line and a line Y-Y are cut, thereby forming a utility pole.

The electric pole thus formed does not have a degassing process as in the prior art, and therefore does not require disassembling, assembling, sliding, and returning of the mold. Accordingly, the dimensions of the molded product are less likely to be deviated, and a molded product with high dimensional accuracy can be molded, in combination with the fact that the respective mold frames are arranged at fixed positions in a positioned state.

Further, as shown in FIG. 5, the cross-sectional structure of the electric pole has a structure in which a glass roving 4 is disposed in a hardened phenol resin. The generated water and the like are removed to the outside, and also serve as a reinforcing material after molding.

Here, the upper support member 24 is, as described above,
Since the mandrel holding piece 23, which is substantially the same size as the inner surface of the upper end of the outer mold frame 1, is extended slightly longer outward, the upper end of the glass roving 4 is inserted when the mandrel 2 is inserted.
The inner side of the upper end of the outer mold frame 1 is pressed inward, and the cross-sectional arrangement of the glass roving 4 becomes denser toward the outside (see FIG. 5), and the strength against external stress increases.

FIG. 6 is a diagram showing a procedure of a strength test of a utility pole (hereinafter referred to as an inventive utility pole) formed by the method for forming a phenolic resin molded product of the present invention.

In FIG. 6, the dimensions of the utility pole are 7
500mm, diameter is 215mm at base end and 130m at top end
m, the average thickness is 12 mm, and the strength test method is as follows. The bending amount when a different load 7 of 80 kg and 160 kg is applied to the tip with the base end 1170 mm of the horizontally placed utility pole fixed by the fixing device 6 and the tip thereof. Is measured. Therefore, Table 1 shows the average value (three in this example) of the amount of deflection measured by the strength test as a measurement result.

[0035]

[Table 1]

In Table 1, the comparative electric poles compared with the inventive electric poles are the molding dimensions, the phenolic resin 5 used.
The material and the number of glass rovings 4 and the number of glass rovings 4 are the same as those of the inventive utility pole, and the method of not degassing during curing is the same. Place it up to the position of the line,
It differs from the inventive utility pole in that it is not arranged to protrude upward from the upper end of the filling space 3. In other words, the comparative power pole has a structure in which moisture and the like generated during curing by the glass roving 4 are not guided to the outside. The test method is the same as that of the invention utility pole.

As a result, as shown in Table 1, in the case of the inventive electric pole having good dehydration conditions, the average electric pole was 1.4 in comparison with the comparative electric pole.
Not only has 1.5 times the strength, but also the surface condition
While the inventive utility pole was beautiful, the comparative utility pole had numerous countless small recesses, which are considered to be traces of evaporation of residual water inside, which proved the superiority of the inventive utility pole.

In this example, the case where the phenol resin is used alone is shown. However, an aggregate may be mixed with the phenol resin. In this case, the filling space 3 is filled before the phenol resin is injected.
Can be filled with an appropriate amount of aggregate.

Although the string-shaped glass roving 4 has been described as an example of the water-conducting member, the invention is not limited thereto, and other inorganic or organic fibers or cloths or mats thereof may be used. Absent.

Further, in this embodiment, the molding of telephone poles has been described. However, the present invention is not limited to the molding of telephone poles, but may be used in general molding of phenolic resin molded articles such as pipes for water supply and sewerage and pipes for power transmission and distribution protection. can do.

[0041]

As described above, according to the present invention,
In a predetermined mold, a water-conducting member is arranged so that at least a part thereof protrudes outward from a filling space formed by the mold, and the phenol resin is filled in the mold to form a phenol resin. During the curing, the water and the like generated from the phenol resin are cured while being removed to the outside of the filling space by the water-conducting member, so that the degassing step as in the related art becomes unnecessary, and the molding step is simplified. As a result, the production efficiency is improved, and molding of a large molded product can be easily performed, so that the versatility of phenol resin molding can be enhanced. Further, after curing, the water-conducting member also plays a role as a reinforcing material, so that it is possible to improve the weight and the strength. In addition, it is possible to prevent the occurrence of avatars and the like on the surface of the molded article due to the generation of moisture and the like, and to form the molded article surface neatly.

[Brief description of the drawings]

FIG. 1 is a partially broken side view showing a form of a utility pole formed based on a method for molding a phenolic resin molded product according to the present invention.

FIG. 2 is a plan view showing a form of a utility pole.

FIG. 3 is a side view showing a state in which a glass roving is arranged on a mandrel main body.

FIG. 4 is a schematic diagram showing an arrangement of glass rovings projecting upward from a filling space.

FIG. 5 is a sectional view showing a sectional structure of a utility pole.

FIG. 6 is an explanatory view showing a procedure of a strength test of a telephone pole formed by the method for forming a phenolic resin molded product of the present invention.

[Explanation of symbols]

 1 outer formwork 2 mandrel 3 filling space 4 glass roving 5 phenolic resin

Claims (2)

(57) [Claims] 1. A water-conducting member is disposed in a predetermined mold so that at least a part thereof protrudes outward from a filling space formed by the mold, and the phenol resin is filled in the mold. And a method for molding a phenolic resin molded article, which is cured. 2. A water-conducting member is disposed in a predetermined mold so that at least a part thereof protrudes outward from a filling space formed by the mold, and the phenol resin is filled in the mold. A method for molding a phenolic resin molded article, wherein the resin is cured while removing water and the like generated from the phenolic resin to the outside of the filling space by the water conducting member.