JPH11230078A - Corrosion preventing structure for device with liquid contact section - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a liquid from impregnating into a gap section by using a water-repellent material or a material coated with the water-repellent material as the material of a liquid contact section or the gap section existing on the liquid contact section. SOLUTION: A spigot coupling section is provided with a flange section 2 at the lower end of a barrel section 1 and a spigot section 5 at the upper end of the flange section 4 of a barrel section 3. The coating 7 of a water- repellent material is applied to connection sections such as the front of the spigot section 5, the inner face of the barrel section 1, and the inner face of the barrel section 3. Fluororesin coating, fluororesin lining or a fluororesin paint is used for the coating 7 of the water-repellent material, for example. When the spigot coupling section is assembled, a slight gap exists between the lower end of the barrel section 1 and the upper end of the barrel section 3, however both sides of this gap section are covered by the coating 7 of the water-repellent material, thus a corrosive liquid flowing on the inner faces of the barrel sections 1, 3 is prevented from impregnating by the water repelling action of the coating 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus provided with a liquid contact part such as a pump for handling corrosive liquids such as seawater, for preventing corrosion of the liquid contact part and a gap existing in the liquid contact part. The present invention relates to a structure for preventing corrosion.

[0002]

2. Description of the Related Art Various devices, such as pumps for handling corrosive liquids such as seawater, have a liquid contact portion that comes into contact with the corrosive liquid and avoid assembling components such as casings by combining components. It is difficult, and a gap is inevitably formed in the liquid contact part. Then, there is a problem that corrosion occurs in the liquid contact portion and the gap. Conventionally, as measures to prevent such corrosion of liquid-contact parts and gaps, liquid-contact parts are coated with a corrosion-resistant material such as resin, or a liquid packing agent is applied to the gaps. In addition, measures have been taken to apply a filler or to fill the gap in the centering spigot portion of the flange.

[0003]

However, the above-mentioned conventional countermeasures for preventing corrosion of the liquid contact portion and the gap existing in the liquid contact portion have not completely prevented corrosion, and in particular, the corrosion has not occurred in the gap. There is a problem that the permeable liquid permeates and causes crevice corrosion. Therefore, when the corrosion is severe, important parts such as a casing are hindered, and replacement has been forced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and in a device such as a pump for handling a corrosive liquid such as seawater, corrosion of a liquid contact part and a gap existing in the liquid contact part is completely prevented. It is an object of the present invention to provide a corrosion prevention structure that can be used.

[0005]

In order to solve the above-mentioned problems, the present invention uses a water-repellent material as a material of the liquid-contact portion and a gap existing in the liquid-contact portion of an apparatus having a liquid-contact portion. Or a material provided with a coating of a water-repellent material.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an example of a corrosion prevention structure according to the present invention. Here, a structure for preventing corrosion of the clearance of the spigot fitting portion will be described. As shown in FIG. 1A, the spigot fitting portion is provided with a spigot portion 5 at the lower end of the body portion 1 and at the upper end of the flange portion 4 of the shank portion 3.
And the front of the spigot part 5, the inner surface of the trunk part 1, and the trunk part 3
A coating 7 of a water-repellent material is applied to a connection portion such as an inner surface of the device. As the coating 7 of the water repellent material, for example, a fluororesin coating, a fluororesin lining, a fluororesin-based paint or the like is used. Reference numeral 6 denotes an O-ring.

[0007] As described above, in front of the spigot portion 5, the trunk portion 1
Although the coating 7 of the water-repellent material was applied to the inner surface of the body and the inner surface of the body 3, when the spigot fitting portion was assembled, as shown in FIG.
A gap portion 8 having a very small gap d is generated between the lower end of the body portion 1 and the upper end of the body portion 3. However, since both sides of the gap portion 8 are covered with the water-repellent material 7, The corrosive liquid flowing through the inner surfaces of the body portions 1 and 3 does not penetrate into the gap 8 due to the water-repellent action of the gap 7, and thus no gap corrosion occurs.

[0008] By applying a water-repellent material to the surface of a liquid-contacting portion of a pump or the like handling a corrosive liquid such as seawater or the like, a corrosive liquid on the gap is provided. Is prevented, and crevice corrosion can be effectively prevented. In the above example, the structure in which the surface of the liquid contact portion or the gap is coated with a water-repellent material is shown, but the members constituting the liquid contact portion or the gap itself may be formed of a water-repellent material.

FIG. 2 is a view showing a vertical section of a vertical pump using the corrosion prevention structure of the present invention. Body parts 20, 21, 2
2, 23 and the suction part 24 are connected by a spigot part 25 having a corrosion prevention structure as shown in FIG.
Reference numeral 26 denotes a motor configured to drive a shaft 28 via a joint 27 and to further drive an impeller 29 provided at the tip of the shaft 28. The surface of the liquid contacting part of the vertical pump is coated with a water-repellent material.

As described above, the liquid contact portion of the vertical pump and the body portions 20, 21, 22, 23 and the suction portion 24 are connected by the spigot portion 25 as shown in FIG. Corrosion of the part and crevice corrosion of the gap existing in the liquid contact part can be prevented.

Although the above embodiment has been described by taking as an example the gap existing in the spigot fitting portion, the present invention is not limited to this, and the liquid contact portion of an apparatus for handling a corrosive liquid such as seawater. And can be widely applied to a gap existing in the liquid contact portion.

[0012]

As described above, according to the present invention, a water-repellent material is used or a material coated with a water-repellent material is used as a material of a liquid-contacting portion or a gap existing in the liquid-contacting portion. Since the liquid repellent action of these water-repellent materials is used, the liquid does not penetrate into the gap, and as a result, in an apparatus using a corrosive liquid, a liquid stagnation region or dead water region is eliminated from the gap of the liquid contact portion, An excellent effect of preventing corrosion of the liquid contact portion and the gap can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing an example of a corrosion prevention structure according to the present invention.
FIG. 1A is a view showing components of a spigot fitting portion, FIG.
(B) is a figure which shows the state which assembled the spigot fitting part.

FIG. 2 is a view showing a vertical section of a vertical pump using the corrosion prevention structure of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body part 2 Flange part 3 Body part 4 Flange part 5 Inlay part 6 O-ring 7 Cover of water-repellent material 8 Gap part 20-23 Body part 24 Suction part 25 Inlet part 26 Motor 27 Joint 28 Shaft 29 Impeller

Claims (1)

[Claims] 1. A water-repellent material or a material coated with a water-repellent material is used as a material of the liquid-contact portion and a gap existing in the liquid-contact portion of an apparatus having a liquid-repellent portion. A corrosion prevention structure in an apparatus having a liquid contact part, characterized by comprising: