JP2007146974A - Hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hose capable of achieving excellent pressure resistance and negative pressure resistance and maintaining flexibility while reducing cost further on the condition that a desalinized vinyl material is used. <P>SOLUTION: This hose is constituted in such a way that it has substantially flat inner and outer faces for joining a soft resin part and a hard resin part extending spirally and having substantially the same thickness mutually and alternately along the longitudinal direction, the soft resin part is constituted by a mixture containing polyolefin resin and thermoplastic elastomer, the hard resin part is constituted by polyolefin resin and filler, and a ratio of cross sectional area of the soft resin part to that of the hard resin part in a vertical cross section of the hose is 1:2 to 1:5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hose suitable for use as a suction / drainage hose in various fields such as industrial, agricultural, and civil engineering sites, foods, beverages, liquor hoses, and solids (powder) transportation hoses.

  As this type of hose, for example, there is one in which a core material made of hard polyvinyl chloride is embedded in a spiral shape in an intermediate layer of a hose body formed of soft polyvinyl chloride. In addition, in order to prevent wear on the inner surface, the inner surface layer formed mainly of a polyester-based thermoplastic polyurethane resin and a soft vinyl chloride resin in which a helical reinforcement body made of hard vinyl chloride resin is embedded in the thickness is formed. There has also been proposed an abrasion-resistant hose that is formed by integrating an outer surface protective reinforcing layer by heat fusion (for example, see Patent Document 1).

  However, such conventional polyvinyl chloride hoses generate dioxins, hydrogen chloride gas, sulfur oxides and other harmful gases during combustion, and thus have environmental problems. Therefore, it has been proposed to use elastomers such as styrene elastomers or olefin elastomers as the soft resin for the hose body and polypropylene as the hard resin for the core material. In addition to causing an increase, impact cracking may occur in the hard resin, particularly in cold regions.

Japanese Patent Application Laid-Open No. 11-141753

  Therefore, in view of the above-mentioned situation, the present invention is based on the premise that a polyvinyl chloride material is used, and further, a hose that is excellent in pressure resistance, negative pressure resistance, and can maintain flexibility while suppressing cost. The point is to provide.

  In order to solve the above-mentioned problem, the present invention provides a hose having a substantially flat inner and outer surfaces in which a soft resin portion and a hard resin portion having substantially the same thickness extending in a spiral shape are alternately joined along the longitudinal direction. The resin part is composed of a mixture including a polyolefin resin and a thermoplastic elastomer, and the hard resin part is composed of a polyolefin resin and a filler, and the cross-sectional area ratio of the soft resin part and the hard resin part in the hose longitudinal section Was a hose characterized by having a ratio of 1: 2 to 1: 5.

  Here, it is preferable that the volume ratio of the soft resin portion to the hard resin portion is 1: 2 to 1: 5.

  Moreover, what made mass ratio of a soft resin part and a hard resin part 1: 2.3 to 1: 6 is preferable.

  Furthermore, the ratio of the hose inner diameter to the wall thickness is preferably 1: 0.02 to 1: 0.06.

  Moreover, what joined so that a soft resin part may partially cover at least one of the hose inner and outer surfaces in the said hard resin part is preferable.

  Further, it is preferable that the soft resin portion is composed of a mixture containing a hydrogenated polystyrene thermoplastic elastomer and a polyolefin resin, and the hard resin portion is composed of a polyolefin resin and a filler.

  The hose according to the present invention formed as described above does not embed a hard core material in the intermediate layer of the soft hose body as in the prior art, but the soft resin portion and the hard resin portion having substantially the same thickness extending spirally. Are hose with a substantially flat inner and outer surfaces joined together along the longitudinal direction, and the use of a soft resin material can be reduced due to its structure.

  The soft resin part is composed of a mixture containing a polyolefin resin and a thermoplastic elastomer, and the hard resin part is composed of a polyolefin resin and a filler. The specific gravity is smaller than that of the vinyl chloride resin. The size can be reduced by about 40%. In addition, the dechlorinated vinyl product can solve the above environmental problems, while the soft resin portion can exhibit sufficient flexibility, and the hard resin portion can exhibit sufficient strength by the filler, Since the pressure resistance and the negative pressure resistance can be maintained, it is possible to reduce the overall thickness, improve the flexibility of the entire hose, further reduce the weight, and improve the workability.

  In particular, the cross-sectional area ratio of the soft resin portion and the hard resin portion in the longitudinal cross section of the hose is 1: 2 to 1: 5, and sufficient flexibility is provided while minimizing the use of soft resin that causes high costs. While being able to maintain, since a hard resin part increases, the intensity | strength rises and the extension of the hose when an internal pressure rises can also be fully suppressed.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing an overall configuration according to the present invention. FIGS. 1 to 3 show typical embodiments. Reference numerals 1A to 1B are hoses, S is a soft resin portion, and R is a hard resin portion. Each is shown.

  As shown in FIG. 1 (a), the hose 1A of the present invention has a substantially inner and outer surface in which a soft resin portion S and a hard resin portion R having substantially the same thickness extending in a spiral shape are alternately joined along the longitudinal direction. It is a flat hose, the soft resin part S is comprised with the mixture containing polyolefin resin and thermoplastic elastomer, and the hard resin part R is comprised from the polyolefin resin and the filler.

  The soft resin portion S is preferably composed of a mixture containing a hydrogenated polystyrene-based thermoplastic elastomer and a polyolefin resin. Examples of the hydrogenated polystyrene-based thermoplastic elastomer include a styrene-ethylenebutylene-styrene block copolymer. In addition, a polypropylene resin, a polyethylene resin, or the like can be used as the polyolefin resin.

  In addition, as the polyolefin resin constituting the hard resin portion R, polypropylene resin or polyethylene resin can be used, and as fillers, powders such as silica, mica, talc, calcium carbonate, titanium oxide, etc. It is preferable to use a filler or a fibrous filler such as glass fiber.

  As a method for producing such a hose, for example, a soft resin portion and a hard resin portion can be obtained by continuously melting and extruding a flexible resin portion and a hard resin portion, spirally wound around a rotating shaft, and sequentially welded.

  And the cross-sectional area ratio of the soft resin part S and the hard resin part R in a hose longitudinal cross section is set to 1: 2 to 1: 5, and the volume ratio of the soft resin part S and the hard resin part R is 1: The mass ratio of the soft resin portion S to the hard resin portion R is set to 1: 2.3 to 1: 6.

  The reason why a relatively large proportion of the hard resin portion R can be set in this way is that the strength is improved because the hard resin portion R includes the filler as described above. In the present invention, the hard resin portion having a circular or elliptical shape is embedded in the soft resin portion, whereas in the present invention, the hard resin portion R has a substantially rectangular shape or a long elliptical shape. It becomes a form continuously joined by the soft resin portion S along the longitudinal direction, and its thickness can be made thinner than the conventional one.

  Specifically, in the present embodiment, the ratio between the hose inner diameter and the wall thickness is 1: 0.02 to 1: 0.06, and the hose is excellent as a whole despite the large proportion of the hard resin portion R. In addition, it achieves light weight by exhibiting the softness and flexibility.

  In addition, as shown in FIGS. 2 and 3, it is also possible to form a covering portion 2 that is partially covered with the soft resin portion S on at least one of the inner and outer surfaces of the hose in the hard resin portion R. It is preferable in that it can be performed.

  Hereinafter, various tests of Examples 1 to 3 and Comparative Examples 1 to 3 of the present invention will be described.

(Description of Examples)
In Examples 1 to 3, a styrene-ethylenebutylene-styrene block copolymer and a polypropylene resin were used for the soft resin portion S, and a polypropylene resin and talc were used for the hard resin portion R. Example 1 is the form shown in FIG. 1, Example 2 is the form shown in FIG. 2, Example 3 is the form shown in FIG. 3, and as shown in Table 1, the sizes are φ50, φ75, and φ100, respectively. Configured.

The longitudinal cross-sectional area ratio and volume ratio of the soft resin portion S and the hard resin portion R are 1: 3.54 (22:78) in Example 1 and 1: 3.16 (24:76) in Example 2, and Example 3 is set to 1: 2.33 (30:70).
The mass ratio of the soft resin portion S to the hard resin portion R is 1: 4.26 (19:81) in Example 1, 1: 3.76 (21:79) in Example 2, and in Example 3. 1: 2.7 (27:73).
Further, the ratio between the hose inner diameter and the wall thickness is 1: 0.059 (50.5: 3) in Example 1, 1: 0.042 (75.5: 3.2) in Example 2, and Example 3 is set to 1: 0.042 (101.0: 4.3).

(Description of comparative example)
Comparative Examples 1 to 3, as in the examples, are substantially flat hoses in which the soft resin portions and the hard resin portions having substantially the same thickness extending in a spiral shape are alternately joined along the longitudinal direction, The soft resin portion and the hard resin portion were made of soft vinyl chloride resin and hard vinyl chloride resin, respectively, and the sizes were φ50, φ75, and φ100, respectively, so as to correspond to the examples.

The longitudinal cross-sectional area ratio and volume ratio of the soft resin portion S and the hard resin portion R are 1: 0.92 (52:48) in Comparative Example 1, 1: 1.38 (42:58) in Example 2, and Example 3 is set to 1: 1.94 (34:66).
The mass ratio of the soft resin part S to the hard resin part R is 1: 1.04 (49:51) in Example 1, 1: 1.56 (39:61) in Example 2, and Example 3 1: 2.22 (31:69).
In addition, the ratio of the inner diameter of the hose to the wall thickness is 1: 0.068 (50.8: 3.5) in Example 1, 1: 0.056 (76.2: 4.3) in Example 2, Example 3 is set to 1: 0.054 (101.6: 5.5).

  In Examples 1, 2, and 3, compared to Comparative Examples 1, 2, and 3 of the same size, the area ratio, volume ratio, and mass ratio of the hard resin portion R are large, and the thickness per inner diameter is thin. I understand that.

(Water pressure test)
The result of having done the water pressure test about these Examples 1-3 and Comparative Examples 1-3 is shown in Tables 3-5, respectively.
Table 3 shows the measurement of the elongation (%) along the longitudinal direction of the hose when water is pressurized from both ends into each hose of Example 1 and Comparative Example 1 of φ50 size. .

From Table 3, although Example 1 had a lower fracture pressure than Comparative Example 1 (0.85 MPa (8.67 kgf / cm ² )), normally used allowable pressure of 0.25 MPa (2.55 kgf / cm ² ). While the elongation rate up to 4.1% is very small, Comparative Example 1 has already increased by 11.3% at the same water pressure, and Example 1 has better pressure resistance than Comparative Example 1. I understand that.

Table 4 shows the measurement of the elongation (%) along the longitudinal direction of the hose when water is pressurized from both ends into each of the hose of Example 2 and Comparative Example 2 of φ75 size. .
From Table 4, Example 2 had a lower fracture pressure than Comparative Example 2 (0.75 MPa (7.65 kgf / cm ² )), but normally used allowable pressure of 0.25 MPa (2.55 kgf / cm ² ). While the elongation rate up to 4.4% is very small, Comparative Example 2 has already increased by 9.8% at the same water pressure, and Example 2 has better pressure resistance than Comparative Example 2. I understand that.

In Table 5, water is pressurized from both ends into each hose of Example 3 and Comparative Example 3 having a φ100 size, and the elongation (%) along the longitudinal direction of the hose at that time is measured. .
From Table 4, although the breaking pressure of Example 3 was lower than that of Comparative Example 3 (0.65 MPa (6.33 kgf / cm ² )), the allowable pressure normally used was 0.2 MPa (2.04 kgf / cm ² ). While the elongation rate up to 3.9% is very small, Comparative Example 3 has already grown 6.8% at the same water pressure, and Example 3 is thinner than Comparative Example 3. Nevertheless, it can be seen that the pressure resistance is excellent.

(Decompression temperature test, bending test)
Table 6 shows the results of performing a reduced pressure deformation temperature test and a bending test for Examples 1 to 3 and Comparative Examples 1 to 3, respectively.
In the reduced pressure deformation temperature test, the hose was heated in a state where the pressure in the hose was reduced to -0.098 MPa, and the temperature when the hose was crushed was measured. In the bending test, both ends of the hose were bent in the same direction, and the radius until breaking was measured.

  As can be seen from Table 6, each of Examples 1 to 3 is not deformed to a higher temperature than Comparative Examples 1 to 3 of the same size, and despite having a relatively small thickness, pressure resistance and negative pressure resistance. It turns out that it is excellent in. Further, the bending radius is the same as that of the comparative example of the same size, and it can be seen that sufficient flexibility is maintained while the hard resin portion is increased.

Moreover, about the mass of a hose, although there is a difference in specific gravity, since thickness can be made very thin, as can be seen from Tables 1 and 2, Examples 1 to 3 are compared with Comparative Examples 1 to 3 of the same size. It can be seen that it is very lightweight and has excellent workability.
In addition, as a result of a strength test in which each hose was stepped on a truck with a predetermined weight and the deformed portion was returned to a circle with a hammer, the hard resin portion was cracked in the hoses of Comparative Examples 1 to 3, while the Example In the hoses 1 to 3, it was confirmed that the hard resin portion was only cracked and did not crack, and that the hose of the present invention had excellent strength.

Explanatory drawing which shows the hose which concerns on Example 1 of this invention. Explanatory drawing which shows the hose which concerns on Example 2 of this invention. Explanatory drawing which shows the hose which concerns on Example 3 of this invention.

Explanation of symbols

1A to 1C Hose 2 Covering part S Soft resin part R Hard resin part

Claims (6)

In a hose having a substantially flat inner and outer surfaces in which soft resin portions and hard resin portions having substantially the same thickness extending in a spiral shape are alternately joined along the longitudinal direction,
The soft resin part is made of a mixture containing a polyolefin resin and a thermoplastic elastomer, and the hard resin part is made of a polyolefin resin and a filler, and the soft resin part and the hard resin part in the longitudinal section of the hose are cut off. A hose characterized by having an area ratio of 1: 2 to 1: 5.   The hose according to claim 1, wherein the volume ratio of the soft resin portion to the hard resin portion is 1: 2 to 1: 5.   The hose according to claim 1 or 2, wherein a mass ratio of the soft resin portion and the hard resin portion is 1: 2.3 to 1: 6.   The hose according to any one of claims 1 to 3, wherein a ratio of the hose inner diameter to the wall thickness is set to 1: 0.02 to 1: 0.06.   The hose according to any one of claims 1 to 4, wherein at least one of the inner and outer surfaces of the hose in the hard resin portion is joined so as to partially cover the soft resin portion. The soft resin portion is composed of a mixture containing a hydrogenated polystyrene-based thermoplastic elastomer and a polyolefin-based resin, and the hard resin portion is composed of a polyolefin-based resin and a filler. The hose according to item 1.

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