JPH04327177A - Corrosion preventive device for large-sized tank - Google Patents

Abstract

PURPOSE:To prevent the occurrence of corrosion at the lower part of a side plate and at an anchor bolt and its place of tightening a nut on a large-sized tank having a supporting arm projecting from the outer side face of the tank side plate passed through the anchor bolt provided on the tank foundation and a nut screwed thereon. CONSTITUTION:The region of a large-sized tank extending from its side plate 2 to the foundation 3 is adhesively covered with a sealing strip 10 excellent in weatherability and flexibility with a sufficient flexing allowance and a supporting arm 5 and the tank foundation 3 are covered with the cylindrical sealing bodies 11 and 12 excellent in weatherability and stretchability for the lower and upper application in a manner to effect the outer covering of an anchor bolt 6 and its place of tightening a nut 7.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrosion prevention device for large tanks for storing naphtha, crude oil, etc.

0002

2. Description of the Related Art Generally, in this type of tank, as shown in FIG. It is attached by welding 4, and a concrete block layer b is laid under the extension of this tank side plate 2, and a ring-shaped building foundation 3 is arranged around the tank separately from these foundations. A plurality of support arms 5 are horizontally protruded from the outer surface of the tank side plate 2 at required intervals in the circumferential direction, and each support arm 5 is attached to an anchor planted at a predetermined position on the building foundation 3. A nut 7 is inserted through the bolt 6 and screwed onto the end protruding from the upper surface of the support arm 5, thereby preventing the tank from skidding or overturning. Furthermore, in order to prevent corrosion of the lower part of the tank, a sealant c is packed between the peripheral edge 8 of the tank bottom plate 1 and the asphalt sand layer a on the building foundation 3, and the sealant c is packed between the lower part 9 of the tank side plate 2 and the tank bottom plate 1. A sealing material d is applied to the peripheral edge 8 of. Note that e in the figure is a gravel layer.

0003

[Problems to be Solved by the Invention] However, in this type of tank, the bottom plate of the tank is damaged depending on whether the inside of the tank is filled with liquid such as naphtha or crude oil, when it is not filled with liquid at all, or due to changes in the amount of filling. 1 and building foundation 3
A significant behavior occurs between the state shown by the solid line in FIG. 1 and the state shown by the chain line in FIG. A crack had developed in the sealing material c between the base plate and the base plate, and rainwater and salt water had entered through the crack, corroding the area from the bottom plate periphery 8 to the lower side plate 9 in a short period of time.

Furthermore, in this type of tank, the anchor bolt 3 and nut 7, which prevent the tank from skidding or overturning via the support arm 5, are exposed to the outside air as shown in the figure. Since they are exposed to the effects of salt water and sea breeze, they are subject to severe corrosion, and in particular, the screws and the bases of the bolts 3 are eroded in a short period of time, resulting in a problem in that the skid and fall prevention function is impaired.

[0005]

[Means for Solving the Problems] The present invention has solved the above-mentioned problems, and the means for that purpose is to provide a sealing strip with excellent weather resistance and flexibility between the tank side plate and the building foundation. In addition to covering and adhering with sufficient flexibility, a sealing cylindrical body with excellent weather resistance and elasticity is attached to the support arm and the building foundation so as to cover the anchor bolt and nut fixing parts. It is characterized by being adhesively bonded to the other side.

Specifically, the sealing cylindrical body includes a lower sealing cylindrical body that is open at both upper and lower ends and encloses the anchor bolt between the lower surface of the support arm and the building foundation, and a lower sealing cylindrical body that is open at both upper and lower ends. It consists of an upper sealing cylindrical body whose lower end is open to cover the bolt and nut parts protruding from the upper surface, and the lower sealing cylindrical body has its upper end attached to the lower surface of the support arm and its lower end attached to the upper surface of the building foundation. The lower end of the upper sealing cylindrical body is adhered to the upper surface of the support arm. Moreover, in this case, it is preferable to form a bellows part on at least a part of each of the lower sealing cylindrical body and the upper sealing cylindrical body.

[0007]

[Embodiment] Next, an embodiment will be explained with reference to FIG. 1. In the corrosion prevention device of the present invention, a sealing strip 10 is installed from the lower part 9 of the tank side plate 2 to the ring-shaped building foundation 3.
are coated and bonded with sufficient bending margin, and lower and upper sealing cylindrical bodies 11 and 12 similar to this sealing band plate 10 are used to secure each anchor bolt 6 and its nut 7, respectively. The support arm 5 and the building foundation 3 are each bonded to the support arm 5 and the building foundation 3 in a encapsulating manner.

[0008] To explain the above structure in more detail,
The sealing band plate 10 is made of a material with excellent weather resistance, flexibility, and flame retardancy, such as silicone rubber.
In adhering this sealing band plate 10, first, the outer circumferential surface of the tank side plate lower part 9 is prepared by polishing with a sander, etc., and the outer circumferential surface is filled with an adhesive made of the same silicone rubber. This overlay part 13
The other end 10b of the sealing strip 10 is glued to the top surface of the ring-shaped building foundation 3 using the same silicone rubber adhesive as the overlay part 13. The lower part 9 of the tank side plate and the peripheral edge 8 of the tank bottom plate 1 are encapsulated and sealed together.

[0009] Furthermore, the outer peripheral edge of the tank bottom plate 1 and the building foundation 3
A built-up part 15 of silicone rubber adhesive is placed on the corner with the top surface of the
A diameter of 10 mm is provided on the inner peripheral side of this built-up portion 15.
A string-like sealing material 16 made of urethane about a millimeter thick is laid in a ring shape. Also, the other end 10b of the sealing band plate 10
When adhering to the building foundation 3, as illustrated in FIG. It is preferable that the anchor bolt 3 is inserted through the insertion hole 17 and then bonded onto the building foundation 3.

[0010] Next, lower and upper sealing cylindrical bodies 1 that enclose each anchor bolt 6 and its nut 7 fixing portion are installed.
1 and 12 are each made of silicon, which is a material with excellent weather resistance, flexibility, and flame retardancy, similar to the sealing strip 10, and the lower sealing cylindrical body 11 is
As shown in the figure, it is formed into a cylindrical shape having an inner diameter sufficiently larger than the diameter of the anchor bolt 6 and a required axial length, and a bellows portion 18 is formed at the upper end.
The bellows portion 18 allows the cylindrical body 11 to easily expand and contract in the axial direction. Further, as shown in the figure, the upper sealing cylindrical body 12 is formed into a bottomed cylindrical shape with an upper end closed and having an inner diameter sufficiently larger than the diameter of the nut 7 and a required length in the axial direction. A bellows part 19 is formed in the upper half, and the bellows part 19 allows for easy expansion and contraction in the axial direction.

In order to cover and bond the lower sealing cylindrical bodies 11 and the upper sealing cylindrical bodies 12, first, before each supporting arm 5 is inserted into each anchor bolt 6, this anchor The lower sealing cylindrical body 11 is loosely fitted concentrically to the bolt 6, and the lower end of this cylindrical body 11 is inserted into the insertion hole 17 of the sealing band plate 10 described above, and the outer periphery of the insertion hole 17 is inserted. Load silicone adhesive along the draining section 2.
0, and this drainage part 20 and the above-mentioned built-up part 14
The lower end of the cylindrical body 11 is bonded to the sealing strip 10 and the building foundation 3 through the sealing strip 10 and the building foundation 3.

Next, each support arm 5 is inserted into each anchor bolt 6 protruding from the lower sealing cylindrical body 11 through the insertion hole 5a, and the support arm 5 is inserted at a required height from the upper surface of the building foundation 3. The base end of the arm 6 is fixed to the outer peripheral surface of the tank side plate 2 by welding, and the upper end of the lower sealing cylindrical body 11 is adhered to the lower surface of the support arm 3 with silicone adhesive, and the outer peripheral edge of the adhesive part is A drainage portion 21 of the same silicone adhesive is formed along the same line.

Next, two nuts 7, 7 are screwed onto the upper end of the bolt 6 protruding from the support arm 3 (
The lower nut 7 is for tightening, the upper nut 7 is for locking), and an upper sealing cylindrical body is provided at the upper end protrusion of these nuts 7 and the bolt 6 protruding from these, that is, the nut fixing part. 12 concentrically, and its lower end is glued to the upper surface of the support arm 5 with silicone adhesive,
A draining portion 22 of silicone adhesive similar to that described above is formed along the outer periphery of the adhesive portion.

As described above, the lower sealing cylindrical body 1
1, the anchor bolt 6 is encapsulated and sealed between the lower surface of the support arm 5 and the upper surface of the building foundation 3, and the nut fixing portion is encapsulated on the upper surface side of the support arm 5 by the upper sealing cylindrical body 12. Seal. As a result, corrosion of each anchor bolt 6 and the nut fixing portion can be completely prevented.

In the corrosion prevention device of the embodiment as explained above, due to the uneven settling of the tank, the tank bottom plate 1,
When the tank side plate 2 and the support arm 5 are respectively lowered from the position shown by the solid line to the position shown by the chain line in FIG. The upper sealing cylindrical body 12 will not be destroyed, the adhesive parts with the supporting arm 5, the adhesive parts with the sealing strip 10 and the building foundation 3 will not be damaged or missing, and the upper sealing cylindrical body 12
The support arm 5 is also retractable around the bellows portion 19.
When the anchor bolt 6 is lowered, it will not hit the top of the anchor bolt 6 and be destroyed, and the bonded part with the support arm 5 will not be damaged or broken. Furthermore, the sealing band plate 10 covering the area from the tank side plate lower part 9 to the building foundation 3 is curved to have a rounded cross section as shown in the figure, and is provided with sufficient bending margin. Even if a level difference occurs between the tank bottom plate 1 and the building foundation 3 due to the above-mentioned subsidence phenomenon, this strip plate 10
By bending from the state shown by the solid line to the state shown by the chain line, the difference in level can be sufficiently absorbed.

Furthermore, even if the tank sways or slightly skids, the sealing cylindrical bodies 11 and 12 have sufficient gaps between the bolts 6 and nuts 7, and the sealing Since the band plate 10 has a bending margin, it is possible to prevent the cylindrical bodies 11, 12 and the band plate 10 from being destroyed and each bonded portion from being damaged or missing.

Furthermore, a built-up part 15 of silicone adhesive is interposed between the outer peripheral edge of the tank bottom plate 1 and the building foundation 3,
In addition, since a string-like sealing material 16 is disposed inside the sealing material 16, the underground water that is about to overflow from the gravel layer e to the outside of the tank bottom plate 1 through the asphalt sand layer a is absorbed by the sealing material 16 and the meat. The raised portion 15 prevents it from overflowing, and prevents it from entering the gap 23 formed inside the sealing band plate 10.

In the embodiment described above, the end portion 10b of the sealing band plate 10 is inserted into the sealing cylindrical body 11 loosely fitted to each anchor bolt 6, and the sealing cylindrical body 11 and the building are Although the end portion 10b of the sealing strip plate is bonded to the foundation 3, it may be bonded only to the building foundation 3 without passing it through the sealing cylindrical body 11. In this case, the lower end of the sealing cylindrical body 11 only needs to be adhered to the building foundation 3. Further, the bellows portions 18, 19
is provided to improve the axial elasticity of the sealing cylindrical bodies 11 and 12, and although it is not necessarily necessary, it is preferable to provide it in at least a portion of the sealing cylindrical bodies 11 and 12. .

[0019]

Effects of the Invention The corrosion prevention device of the present invention prevents the difference in level between a large tank and the foundation of a building around the tank due to behavior phenomena of the tank side plate and tank bottom plate due to the weight of the contents of the large tank, uneven settlement phenomenon, etc. Even if this happens, the sealing strip will bend following the step, and the tensile stress generated when the step occurs will cause the strip itself to break or the bonded parts to the tank side plate and the building foundation to be damaged. There is no chance of chipping, and therefore complete corrosion protection of the lower part of the tank side plate and the periphery of the tank bottom plate can be achieved for a long period of time.

In particular, in the device of the present invention, a sealing cylindrical body with excellent weather resistance and elasticity is bonded to the support arm and the building foundation so as to cover the anchor bolt and nut fixing portion. Therefore, it is possible to completely prevent corrosion of the anchor bolt and nut fixing parts, which are exposed to the outside air and are affected by salt water and sea breeze, and as a result, the anchor bolt and nut can be used continuously for a long period of time. At the same time, safety in use of the tank can be ensured.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a main part showing an embodiment of a corrosion prevention device for a large tank according to the present invention.

FIG. 2 is a vertical sectional view of a main part similar to FIG. 1 showing a conventional example of this type.

[Explanation of symbols]

1 Tank bottom plate 1a Periphery of tank bottom plate 2 Tank side plate 3 Building foundation 5 Support arm 6 Anchor bolt 7 Nut 9 Lower part of tank side plate 10 Seal band plate 10a　One end of the sealing band plate 10b Other end of sealing band plate 11 Lower seal cylindrical body 12 Upper seal cylindrical body 18 Bellows belly 19 Bellows belly

Claims (3)

[Claims] Claim 1: In a large tank in which a support arm protruding from the outer surface of a tank side plate is inserted into an anchor bolt installed in a building foundation and fixed with a nut, the supporting arm is attached to the tank side plate. In addition, a sealing band plate with excellent weather resistance and flexibility is wrapped and bonded with sufficient flexibility, and a sealing cylindrical body with similar weather resistance and elasticity is attached to the anchor. A corrosion prevention device for a large tank, characterized in that the device is adhesively bonded to the supporting arm and the building foundation so as to cover the bolt and nut fastening portions. 2. The sealing cylindrical body includes a lower sealing cylindrical body that is open at both upper and lower ends and encloses the anchor bolt between the lower surface of the support arm and the building foundation; It consists of an upper sealing cylindrical body with only its lower end open, which covers the bolt and nut parts protruding from the cylindrical body. 2. The corrosion prevention device for a large tank according to claim 1, wherein the upper sealing cylindrical body has a lower end adhered to the upper surface of the support arm. 3. The corrosion prevention device for a large tank according to claim 2, wherein each of the lower sealing cylindrical body and the upper sealing cylindrical body has a bellows portion in at least a portion thereof.