JPH0519357U - Cathodic protection device for steel tank inner surface - Google Patents

Abstract

(57) [Abstract] [Purpose] To make it possible to perform cathodic protection on the inner surface of steel tanks with good workability and ease. [Structure] An end of a galvanic anode plate 5 laid on the upper surface of a bottom plate 1 of a steel tank is provided with a reaction force receiving metal fitting 2, a grooved steel pressing metal fitting 3, and a web 3a of the grooved steel pressing metal fitting 3. It is fixed together with electrical continuity by a fixing means composed of a reaction force applying bolt 4 screwed to the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cathodic protection device for an inner surface of a steel tank such as a crude oil storage tank or a tanker.

[0002]

[Prior Art]

 BACKGROUND ART Conventionally, a cathodic protection device for the inner surface of a steel tank has a main body of a galvanic anode having a rectangular cross section having a required length, a core metal embedded in the inner longitudinal direction of the main body of the galvanic anode, and A flow consisting of a mounting leg plate protruding vertically from the front and rear parts of the core metal to the outside of the lower surface of the galvanic anode body, and a welding plate provided at a right angle to the lower half of one side end surface of each mounting leg plate. It was constructed by placing the galvanic anode main body on the bottom plate upper surface of the steel tank using a positive electrode and welding the above-mentioned welding plate to the bottom long section of the steel tank (see Japanese Utility Model Publication No. 1-173159). ).

[0003]

[Problems to be solved by the device]

 By the way, since the conventional galvanic anode body is heavy, the workability is poor.Since the galvanic anode body is placed on the upper surface of the bottom plate of the steel tank and the welding plate is welded to the bottom long section, When the main body is consumed, there is a problem that a gap is formed between the upper surface of the bottom plate of the steel tank and the main body of the galvanic anode, which makes it difficult for effective anticorrosive current to flow.

[0004]

[Means for Solving the Problems]

 The present invention has been made to solve the above-mentioned conventional problems. The gist of the present invention is to provide a horizontally elongated cutout hole with a lower edge open at the center of the plate on the upper surface of the bottom plate of a steel tank. Weld a reaction force receiving metal fitting, and insert a holding metal fitting a reaction force applying bolt into the center of the reaction force receiving metal fitting at right angles to the horizontally long cutout hole of the reaction force receiving metal fitting. The reaction force application bolt heads are screwed back by abutting the both ends of the presser foot tool on the upper surface of the end of the galvanic anode plate that is laid opposite to the upper surface of the bottom plate of the steel tank, and screwing back the reaction force application bolt. The cathodic protection device for the inner surface of the steel tank is adapted to be brought into contact with the lower surface of the upper edge of the laterally cutout hole of the reaction force receiving fitting.

[0005]

[Action]

 According to the device of the present invention, since the galvanic anode plate is laid on the upper surface of the bottom plate of the steel tank, it is lighter in weight than the conventional galvanic anode body having a rectangular cross section, and thus the workability is improved and The uniform consumption is small, and the oppositely installed galvanic anode plates can be fixed to the upper surface of the bottom plate of the steel tank at the same time by pressing the metal fittings by simply operating the reaction force application bolts. The electrical conduction and fixing work of the anode plate is extremely easy, and even if the galvanic anode plate becomes worn and thin, the galvanic anode plate can be brought into close contact with the upper surface of the bottom plate of the steel tank and is always effective. It is possible to apply an anticorrosion current.

[0006]

【Example】

 1 and 2 show a first embodiment of the present invention, in which a reaction force having a horizontally elongated cutout hole 2a with a lower edge opened at the center of the plate surface of the bottom plate 1 of a steel tank. The receiving metal fitting 2 is welded, and the groove-shaped steel pressing metal fitting 3 into which the reaction force applying bolt 4 is screwed is inserted into the central portion of the web 3a at right angles to the laterally elongated cutout hole 2a of the reaction force receiving metal fitting 2, Both side flanges 3b of the channel-shaped steel pressing metal fitting 3 are brought into contact with the upper surfaces of the end portions of the galvanic anode plate 5 laid opposite to the upper surface of the bottom plate 1 of the steel tank with the reaction force receiving tool 2 as the center. The grooved steel is pushed down by screwing the reaction force applying bolt 4 so that the head of the reaction force applying bolt 4 is brought into contact with the lower surface of the upper edge of the laterally elongated cutout hole 2a of the reaction force receiving metal fitting 2. The galvanic anode plates 5 laid opposite to each other are attached to the bottom plate 1 of the steel tank through the flanges 3b on both sides of the metal holder 3. It is to that can be fixed with electrical continuity to the surface.

FIG. 3 shows a second embodiment of the present invention, in which the reaction force applying bolt is provided on the bolt head and on both sides of the upper edge of the laterally cutout hole 2 a of the reaction force receiving metal fitting 2. A so-called wing bolt 14 having engaging detent wings 14a is used, a nut 6 is screwed onto the wing bolt 14, and the lower end of the wing bolt 14 is attached to the web 3a of the groove-shaped steel pressing fitting 3. After setting the grooved steel pressing metal fitting 3 in the laterally cutout hole 2a of the reaction force receiving metal fitting 2, the butterfly bolt 14 is screwed back to a certain extent, and the detent wing piece 14a is rotated. The lateral cutout hole 2a of the reaction force receiving metal fitting 2 is engaged with both upper side surfaces of the lateral edge, and then the nut 6 is operated to screw the wing bolt 14 backward. It was made to contact the lower surface of the upper edge.

FIG. 4 shows a third embodiment of the present invention, in which the reaction force receiving fitting is a bottom longe 12 in a steel tank, and the horizontally long cutout hole is a horizontally long drainage hole. The other parts are the same as those of the second embodiment shown in FIG. In each of the examples, an insulating coating 7 is applied on the upper surface of the galvanic anode plate 5 around the flanges 3b on both sides of the grooved steel pressing member 3 to quickly wear out the galvanic anode plate 5 around the flanges 3b on both sides. Prevent.

As described above, the insulating coating 7 is applied to the upper surface of the galvanic anode plate 5 around the flanges 3b on both sides of the grooved steel pressing member 3, but this is applied to a new steel tank. However, if there is residual water (bilge) on the bottom plate, as in an existing steel tank, the insulating coating 7 cannot be applied. In this case, as shown in FIG. A required size galvanic anode plate piece 8 having an insulating coating 7 is interposed between the both side flanges 3b and the galvanic anode plate 5. The insulating coating 7 in the fourth embodiment shown in FIG. 5 is not always necessary when the galvanic anode plate pieces 8 are stacked.

FIG. 6 shows a fifth embodiment of the present invention, in which, for example, a steel pipe is half-cut in place of the channel steel pressing fitting 3 in the third embodiment shown in FIG. Such a half-cut steel tubular pressing fitting 3 is used, and the rest is the same as the third embodiment shown in FIG.

FIG. 7 shows a sixth embodiment of the present invention, which is a semi-steel tubular tubular metal fitting in place of the grooved steel pressing metal fitting 3 in the fourth embodiment shown in FIG. 3 is used, and other points are the same as those in the fourth embodiment shown in FIG. In addition, in each of the examples, when the bottom plate is regarded as the side wall, the side wall can also be galvanically protected.

[0012]

[Effect of the device]

 According to the device of the present invention, since the galvanic anode plate is laid on the upper surface of the bottom plate of the steel tank, it is lighter in weight than the conventional galvanic anode body having a rectangular cross section, and thus the workability is improved and The uniform consumption is small, and the oppositely installed galvanic anode plates can be fixed to the upper surface of the bottom plate of the steel tank at the same time by pressing the metal fittings by simply operating the reaction force application bolts. The electrical conduction and fixing work of the anode plate is extremely easy, and even if the galvanic anode plate becomes worn and thin, the galvanic anode plate can be brought into close contact with the upper surface of the bottom plate of the steel tank and is always effective. It is possible to apply an anticorrosion current.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a sectional view showing a third embodiment of the present invention.

FIG. 5 is a sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a fifth embodiment of the present invention.

FIG. 7 is a sectional view showing a sixth embodiment of the present invention.

[Explanation of symbols]

1 Bottom plate of steel tank 2 Reaction force receiving metal fitting 12 Bottom longe 2a Horizontal notch hole 12a Drain hole 3 Groove-shaped steel pressing metal fitting or semi-steel steel tubular pressing metal fitting 4 Reaction force applying bolt 14 Reaction force applying butterfly bolt 5 Galvanic anode plate 6 Nut 7 Insulation coating 8 Galvanic anode plate piece

Claims (3)

[Scope of utility model registration request] 1. A reaction force receiving metal fitting having a horizontally elongated cutout hole with a lower edge opened at the center of the steel plate is welded to the upper surface of the bottom plate of a steel tank,
Insert a holding metal fitting, which is screwed with a reaction force applying bolt in the center, at right angles to the laterally elongated cutout hole of this reaction force receiving metal fitting, and lay opposite to the upper surface of the bottom plate of the steel tank centering on the reaction force receiving metal fitting. By contacting both side ends of the pressing fitting to the upper surface of the end portion of the galvanic anode plate, and screwing back the reaction force applying bolt, the head of the reaction force applying bolt is made into a horizontally long cutout hole of the reaction force receiving metal fitting. A cathodic protection device for the inner surface of a steel tank, which is brought into contact with the lower surface of the upper edge of the steel tank. 2. A bolt having, at the head of the reaction force, a detent wing that engages with the upper edge both side surfaces of the laterally cutout hole of the reaction force receiving metal fitting, and the nut is provided on the bolt. 2. The cathodic protection device for the inner surface of the steel tank according to claim 1, wherein the lower end portion of the bolt is passed through the central portion of the holding metal fitting while being screwed. 3. The steel tank inner surface according to claim 1, wherein the reaction force receiving metal fitting is a bottom longe in a steel tank, and the horizontally elongated cutout hole is a horizontally elongated drain hole. Electrocorrosion protection device.