JP2017207161A - Bolt cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bolt cap which can be easily attached to a bolt fastening portion and suppresses corrosion of this portion by securely sealing the bolt fastening portion. SOLUTION: A bolt cap attached to a bolt fastening portion that seals and covers the outside of a bolt, and prevents communication between an air flow path that communicates inside and outside the bolt cap at the time of attachment / detachment and communication between the flow path at the time of fixing. It is a method of attaching and detaching the bolt cap and a bolt cap that seals and covers the outside of the bolt, which is characterized by providing a sealing means for the bolt cap. Bolt cap to prevent intentionally. [Selection diagram] Fig. 4A

Description

  The present invention relates to a bolt cap used in a building structure, particularly an offshore wind power generation facility.

  In recent years, the momentum of renewable energy power generation has increased worldwide, and as one of them, wind power is attracting attention along with solar power, geothermal power, tidal power, small scale hydropower, etc., and wind power generation facilities mainly in coastal areas and mountainous areas in Japan Construction is becoming prominent.

  Conventionally, wind power generation facilities have been built on land that is easy to construct, but it can be constructed on land, such as noise problems, sunshine problems, securing of sites, the effects of lightning strikes and damages, and the difficulty of obtaining stable wind power. In the future, it will be more likely to be constructed offshore where these problems are less likely.

  However, in offshore construction, sea salt particles adhere more because the sea breeze is stronger than onshore, and metal parts are corroded in a short time. Therefore, anti-corrosion measures must be stricter than onshore construction in terms of durability improvement.

  On the other hand, in the protection of bolts, it is necessary to retighten the bolts to prevent loosening of each part after construction, and in that case, it is necessary to temporarily remove and remove the bolt protectors. As one of the countermeasures, a bolt cap that covers the fastening portion of the bolt with a cap made of an anticorrosive material is effective.

  Conventional anti-corrosion bolt caps are a method in which a hard cap is filled with an adhesive to cover the entire fastening part of the bolt (Patent Documents 1 and 2), or a resin is molded so as to cover the entire fastening part of the bolt. A method (Patent Document 3) using the above is known.

  When both are compared, the bolt cap of Patent Document 3 in which a resin is molded so as to cover the entire fastening portion of the bolt is more desirable because the bolt must be removed by retightening.

Japanese Utility Model Publication No. 4-44513 Japanese Utility Model Publication No. 8-3701 JP 2012-154377 A

  The bolt cap (rust prevention cap) of Patent Document 3 is formed of a material such as resin or rubber, as described in paragraphs 0012 and 0014 of the same document, and it can be used either soft or hard. However, it is considered preferable to use a hard material. Further, as described in paragraph 0022 of the same document, the bolt cap is attached so as not to be easily detached from the bolt / nut assembly.

  That is, the bolt cap of Patent Document 3 has a high hermeticity as is apparent from the respective drawings of the same document, so that air accumulated inside during the mounting becomes resistance, and a large force is required for mounting the bolt cap. There is a possibility that problems such as normal installation are difficult. Further, when the bolt is tightened, it is necessary to remove the bolt cap once. However, if the bolt cap is to be removed, there is a problem that it is difficult to remove the bolt cap because the inside becomes negative pressure.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a bolt cap that can be easily attached and detached while maintaining anticorrosion performance by securely adhering to a bolt fastening portion.

  The above-described problem is a bolt cap that protects a fastening portion between a bolt and a nut, and includes an air communication channel that communicates the inside and the outside of the bolt cap, and a sealing means that closes the air communication channel. Solved by the cap.

  According to the present invention, it is possible to provide a bolt cap that can be easily attached and removed while being securely adhered to a bolt fastening portion and maintaining anticorrosion performance.

Explanatory drawing of flange coupling part in windmill Explanatory drawing of bolt fastening part in flange joint part Enlarged sectional view of the bolt joint The perspective view of the bolt cap of Example 1. Cross-sectional structure of the bolt cap of Example 1 Mounting schematic diagram of the bolt cap of Example 1 Sectional structure of bolt cap of Example 2 Cross-sectional structure of the bolt cap of Example 3

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

  FIG. 1 shows an overall view of a wind turbine 100 according to the first embodiment. As shown here, a set of three blades 21 is attached to the hub 22 of the windmill 100, and the hub 22 rotates by receiving wind force. The rotation of the hub 22 is transmitted to the generator inside the nacelle 23 to generate power. The tower 24 supports the hub 22 and the nacelle 23, and is made by connecting a plurality of metal ring-shaped parts, so that there are many flange connecting parts 25 (indicated by dotted lines) which are parts connecting parts. Exists. Although not shown in FIG. 1, the normal tower 24 is a stack of about 50 metal ring-cut parts having a height of about 2 m. A flange joint 25 is present.

  The principal part of the flange coupling | bond part 25 is shown in FIG. The flange coupling portion 25 has a large number of bolt fastening portions 26 arranged on the circumference. FIG. 3 shows a cross-sectional view of each bolt fastening portion 26. As shown here, the bolt fastening portion 26 is made of resin between an annular upper flange 27 provided at the lower end of the upper ring-shaped part and an annular lower flange 28 provided at the upper end of the lower ring-cut part. The O-ring is sandwiched between the bolts 10 and nuts 29 made of galvanized steel, which are penetrated by the O-rings. The bolt cap 1 which will be described later protects the bolt fastening portion 26 that is most easily corroded and is exposed upward from the upper flange 27 in the joint portion between the bolt 10 and the nut 29.

  4A and 4B are a perspective view and a sectional view of the bolt cap 1 of the first embodiment. The bolt cap 1 is made of a waterproof and anticorrosive flexible material such as polyvinyl chloride, and covers a portion exposed upward from the upper flange 27 of the bolt 10 and the nut 29. A flange 2 is provided at the lower end of the bolt cap 1 so as to be in close contact with the upper flange 27. Furthermore, a protrusion 5 is provided at a position higher than the nut 29 to prevent the belt 3 described later from coming off.

  The dotted lines shown in FIGS. 4A and 4B are the air communication flow path 11 provided around the bolt 10 and the nut 29, and before the belt 3 is tightened, the air is free between the upper space of the bolt 10 and the external space. Circulate in

  A belt 3 made of a thin metal plate or a resin is wound between the projection 5 of the bolt cap 1 and the collar 2. As shown in the lower diagram of FIG. By tightening the belt 3, the resin bolt cap 1 can be deformed and the air communication channel 11 can be closed. That is, in this embodiment, the belt 3 that deforms the bolt cap 1 functions as a sealing means for closing the air communication channel 11. Thereby, the space surrounding the bolt 10 and the nut 29 is sealed by the bolt cap 1, and the bolt 10 and the nut 29 are not corroded even under metal corrosion conditions.

  Further, when it is desired to remove the bolt cap 1 for the purpose of tightening the nut 29 after the attachment, as shown in the upper diagram of FIG. 5, the belt variable length fastening device 4 is loosened and a thin metal plate around the bolt cap 1 is made. Alternatively, the resin belt 3 is removed and the air communication channel 11 is opened. As a result, the space surrounding the bolt 10 and the nut 29 is opened and no negative pressure is generated, so that the bolt cap 1 can be easily removed.

  From the above, since air accumulates inside the bolt cap during installation and resistance occurs during installation, the bolt cap is difficult to install, or the sealing function cannot be obtained properly.

  At the same time, it is necessary to remove the bolt cap once at the time of retightening, but at the time of removal, the belt 3 made of thin metal plate or resin, which is a sealing means around the bolt cap, is loosened until the inner side of the bolt cap is separated from the bolt. It shows the feature that the bolt cap does not become negative pressure and the problem that it is difficult to remove does not occur.

  As described above, according to the configuration of the first embodiment, the air communication flow path 11 that can be freely opened and closed by the belt 3 is provided in the bolt cap 1, so that the bolt fastening portion 26 is securely adhered after the mounting. While maintaining the anticorrosion performance at the bolt fastening portion 26, it is possible to provide the bolt cap 1 that can be easily removed at the time of retightening.

  FIG. 6 shows a cross-sectional view of the bolt cap 1 of the second embodiment. In addition, description is abbreviate | omitted about the point which is common in Example 1, and it demonstrates focusing on the newly provided air vent 12 and the valve | bulb 6. FIG.

  As shown in FIG. 6, the bolt cap 1 of the second embodiment is provided with an air vent 12 that connects the upper space between the bolt 10 and the nut 29 and the outer space, and the air indicated by the dotted line by the operation of the valve 6. The communication channel 11 can be opened and closed.

  That is, in the present embodiment, the valve 6 that closes the air vent 12 serves as a sealing means for closing the air communication channel 11, and the air communication channel 11 is closed by closing the valve 6 and blocking the air passing through the air vent 12. Is closed. As a result, the space surrounding the bolt 10 and the nut 29 is hermetically sealed, so that the bolt 10 and the nut 29 are not corroded even under metal corrosion conditions.

  Further, when it is desired to remove the bolt cap 1 for the purpose of tightening the nut 29 after the attachment, the air communication channel 11 is opened by loosening the valve 6 and releasing the air passing through the air vent 12. As a result, the space surrounding the bolt 10 and the nut 29 is opened, and the bolt cap 1 can be removed without generating negative pressure.

  As described above, since air is accumulated inside the bolt cap and becomes resistance during installation, the bolt cap is difficult to install, or the anticorrosion function is not obstructed such that the sealing cannot be properly obtained.

  At the same time, it is necessary to remove the bolt cap once it is tightened, but opening the valve on the cap head during removal will not cause negative pressure inside the bolt cap, and there is no problem that it is difficult to remove. Show.

  FIG. 7 shows a bolt cap according to the third embodiment. Description of points common to the above embodiment will be omitted. The basis of the present embodiment is the bolt cap of the first embodiment, but the environment in which the bolt cap of the present embodiment is installed is monitored by periodically observing the crevice corrosion test metal piece 13 to be installed. However, the bolt 10 and the nut 29 are protected. In the configuration of this embodiment, when the bolt cap 1 is attached to some of the bolt fastening portions 26 and the bolt cap 1 is not attached to the other bolt fastening portions 26, the bolt fastening portion 26 where the bolt cap 1 is not attached. This is particularly effective in that the progress of corrosion can be predicted.

  The bolt cap 1 is made of a waterproof and anticorrosive material such as polyvinyl chloride, and covers a portion exposed upward from the upper flange 27 of the bolt 10 and the nut 29. At this time, it is essential that the air communication channel 11 indicated by a dotted line is interposed between the bolt 10 and the nut 29. Further, it is essential that the bolt cap 1 and the upper flange 27 are in close contact with the flange 2.

  Next, a belt 3 made of a thin metal plate or a resin is wound around the bolt cap 1, the belt 3 is tightened with a belt variable length tightening device 4, and the air communication channel 11 is closed. As a result, the space surrounding the bolt 10 and the nut 29 is sealed by the bolt cap 1, and the effect that the bolt 10 and the nut 29 are not corroded even under a metal corrosion condition occurs.

  After that, the crevice corrosion test metal piece 13 made of galvanized steel is covered on the protruding portion of the bolt cap 1 like the bolt 10 and the nut 29, and the crevice corrosion test resin plate 14 is covered thereon. As shown in FIG. 7, the crevice corrosion test metal piece 13 is a member larger than the crevice corrosion test resin plate 14, and a predetermined gap is provided therebetween. With this configuration, seawater that enters the tower 24 and falls from above enters the gap between the crevice corrosion test metal piece 13 and the crevice corrosion test resin plate 14 and corrodes the crevice corrosion test metal piece 13. That is, by periodically observing the crevice corrosion test metal piece 13, it is possible to easily predict the progress of corrosion in the bolt fastening portion 26 to which the bolt cap 1 is not attached.

  Although the crevice corrosion test metal piece 13 is made of galvanized steel here, it goes without saying that other metal materials may be used as long as corrosion can be observed. Also, the gap corrosion test resin plate 14 for forming a gap above the gap corrosion test metal piece 13 is made of resin, because if both are made of metal, the two will be integrated due to corrosion. This is because the purpose of the present embodiment to be observed cannot be achieved.

  Further, when it is desired to remove the bolt cap for the purpose of tightening the nut 29 after the attachment, first, the crevice corrosion test resin plate 14 and the crevice corrosion test metal piece 13 are removed from the protruding portion of the bolt cap 1 in this order, and then the belt variable length fastening device. 4 is loosened, the belt 3 made of a thin metal plate or resin around the bolt cap 1 is removed, and the air communication channel 11 is opened. As a result, the space surrounding the bolt 10 and the nut 29 is opened, and the bolt cap 1 can be removed without generating negative pressure.

  According to the present embodiment, when corrosive components such as sea salt particles in the atmosphere adhere between the crevice corrosion test metal piece 13 and the crevice corrosion test resin plate 14, the crevice corrosion test metal piece 13 generates crevice corrosion.

This shows the feature that it is possible to predict the occurrence of crevice corrosion in other metal fitting parts while protecting the bolt body.

1 bolt cap, 2 brim, 3 belt, 4 belt variable length fastening device, 5 protrusion, 6 valve, 10 bolt, 11 air communication channel, 12 air vent, 13 crevice corrosion test metal piece, 14 crevice corrosion test resin plate, 21 Blade, 22 Hub, 23 Nacelle, 24 Tower, 25 Flange joint, 26 Bolt fastening part, 27 Upper flange, 28 Lower flange, 29 Nut, 100 Windmill

Claims (6)

A bolt cap that protects the fastening part of the bolt and nut,
An air communication channel communicating the inside and the outside of the bolt cap;
Sealing means for closing the air communication channel;
A bolt cap comprising: A method for attaching and detaching a bolt cap according to claim 1,
When attaching the bolt cap to the fastening portion, and when removing the bolt cap from the fastening portion, the sealing means is opened and the air communication channel is communicated.
The bolt cap attaching / detaching method, wherein when the bolt cap is fixed to the fastening portion, the sealing means is closed and the air communication channel is not communicated. The bolt cap according to claim 1,
The bolt cap characterized in that the sealing means is a belt made of a thin metal plate or a resin wound around the bolt cap. The bolt cap according to claim 3,
The said belt is wound between the projection part provided in the said bolt cap, and the collar part, The bolt cap characterized by the above-mentioned. The bolt cap according to claim 1,
The bolt cap characterized in that the sealing means is a valve that opens and closes an air vent connecting the inside and outside of the bolt cap. The bolt cap according to claim 1,
A bolt cap comprising a corrosion test metal piece or a corrosion test resin piece.

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