JP6311653B2 - Flange joint reinforcement jig - Google Patents

Description

  The present invention joins the steel pipes by joining the lower horizontal flange part provided at the end of the lower steel pipe and the upper horizontal flange part provided at the end of the upper steel pipe with bolts and nuts. The present invention relates to a flange joint reinforcing jig for reinforcing a flange joint in a tower structure.

As a flange joint reinforcing jig that reinforces a flange joint that joins steel pipes with a flange, for example, there is a flange reinforcing jig disclosed in Patent Document 1.
The flange reinforcement jig disclosed in Patent Document 1 is “a flange reinforcement jig in a flange joint portion of a pipe flange joint, and the flange reinforcement jig is arranged at intervals in the flange circumferential direction so as to straddle the flange joint portion. A plurality of reinforcing members, a contact member pressed against the back surface of the flange portion by the reinforcing member in contact with the root portion of the back surface of the flange portion, and fastening for fixing the plurality of reinforcing members to the tubular body Consisting of parts,
The reinforcing member is in contact with the pressing portion A1 that is in contact with the root portion on the back surface of one flange portion, and the front surface is in contact with the back surface of the abutting member that is in contact with the root portion on the back surface of the other flange portion. A pressing portion A2 that presses against the pressing portion, and a tightening portion A3 that protrudes along the tube wall on the pressing portion A2 side,
The tightening member has a ring shape, and each tightening portion A3 of the plurality of reinforcing members is configured to be tightenable in the central direction of the tube. (See claim 1).

JP 2006-329340 A

As a tower structure in which steel pipes are flange-joined, for example, there is a tower body 31 of a wind power generation facility 29 as shown in FIG.
When wind external force is applied or wind turbine power generation is performed, wind force acts on the blade 33 installed at the top of the tower body 31, so that a tipping moment acts on the tower body 31. Stress is repeatedly applied to the cross section of the tower body 31 by the action of the overturning moment. In general, the operating period of a wind power generation facility is 20 years, but it is assumed that repeated stress of about 200 million times will act in the last 20 years.

As shown in FIG. 10, the tower body 31 of such a wind power generation equipment 29 has an inward upward horizontal flange portion 5 and a lower horizontal flange portion 3 (L-shaped flanges in section) formed at the end of the steel pipe as bolts 35. And a bolt 37 by a nut 37. Therefore, when a wind load is applied to the tower body 31, as shown in FIG. 11, the flange portion opens on the leeward side (FIG. 11 (a)), and on the other side, the pressing force is applied to the flange portion. It works (see FIG. 11B).
In this case, on the windward side of the tower body 31 shown in FIG. 11A, a return stress is generated that repeats due to a “leverage reaction force” with the flange end portion as a fulcrum.
The inward flange (cross-section L-shaped flange) has a feature that this “leverage reaction force” acts on the bolt 35. If the flange portion is wide, the distance between the force point and the fulcrum becomes longer. "Becomes bigger.

  Due to such “leverage reaction force”, there are many cases where the bolts are fatigued and destroyed due to stress concentration or repetitive stress exceeding that assumed in the design, leading to collapse of the wind power generation equipment. In particular, in a wind power generation facility on the terrain where the prevailing wind direction is specified, the stress is concentrated on the bolt at the flange joint portion at a specific portion of the tower body, so that fatigue failure of the bolt occurs locally.

  When a bolt fatigue failure occurs, it will be replaced with a new bolt, but it is assumed that the occurrence of fatigue failure will be concentrated at a specific location, and therefore after the replacement with a new bolt, fatigue failure will occur at the same location. There is a concern that this may occur repeatedly.

Therefore, it is necessary to reinforce a specific flange joint where such fatigue failure occurs, and a reinforcing method using a flange reinforcing jig disclosed in, for example, Patent Document 1 can be considered as a reinforcing method.
However, in this reinforcing method, it is necessary to fix the reinforcing member with a tightening member such as a bolt, a wire, or a belt, and in order to exert a reliable tightening force, it is necessary to appropriately manage the tightening force.
Moreover, since the stress state changes as the tightening force increases, it is difficult to simply evaluate the stress generated in the existing bolt.
In addition, when excessive tightening is performed, the stress borne by the existing bolt is lost, and fatigue failure of the reinforcing material may occur.

  In addition, a large number of bolts are used at bolt joints in large-diameter cylindrical tubes such as towers of wind power generation facilities in order to ensure the necessary proof stress. In particular, in recent years, with the increase in the size of wind power generation facilities, the required proof stress has increased and the number of bolts tends to increase. A lot of man-hours are required to attach the reinforcing material to the joints composed of a large number of bolts.

  The present invention has been made in order to solve such a problem, does not require a tightening member, does not require management of a tightening force, etc., can improve an appropriate fatigue strength, and does not require many man-hours. An object of the present invention is to provide a flange joint reinforcing jig that can be attached to a flange.

(1) A flange joint reinforcing jig according to the present invention includes a lower horizontal flange portion provided at an end portion of a lower steel pipe and an upper horizontal flange portion provided at an end portion of an upper steel pipe by bolts and nuts. A flange joint reinforcing jig for reinforcing the flange joint in the tower structure joined by the steel pipes,
An upper reinforcing member disposed on the flange surface side of the upper horizontal flange portion , and a lower reinforcing member disposed on the lower horizontal flange portion side,
The upper reinforcing member is formed on the upper surface of the upper horizontal flange portion, and is continuously formed on the upper body portion and extends from the end of the upper horizontal flange portion in the installed state. Having an upper extension,
The lower reinforcing member includes a lower main body portion disposed at least partially in contact with a lower surface of the lower horizontal flange portion, and an end of the lower horizontal flange portion formed in an installed state continuously with the lower main body portion. Having a lower extension extending beyond the part,
The upper extension part and the lower extension part have an engaging part that engages with each other and restricts the lower extension part from moving downward, and the upper extension part and the lower extension part are engaged in an engaged state. A gap is formed on the opposing surface of the extending portion, and when the base portion of the upper horizontal flange portion and the lower horizontal flange portion are separated in the vertical direction, the gap is closed and the opposing surface can come into contact. It is characterized by that.

(2) Further, in the above (1), the upper reinforcing member is provided with a hole or notch into which the bolt head of the bolt can be inserted, and the nut is inserted into the lower reinforcing member. A possible notch is provided.

(3) Further, in the above (1), the upper reinforcing member is provided with a notch into which a bolt head of the bolt can be inserted, and the nut can be inserted into the lower reinforcing member. A hole or a notch is provided.

A flange joint reinforcing jig according to the present invention includes an upper reinforcing member disposed on the flange surface side of the upper horizontal flange, and a lower reinforcing member disposed on the lower horizontal flange portion side,
The upper reinforcing member is formed on the upper surface of the upper horizontal flange portion, and is continuously formed on the upper body portion and extends from the end of the upper horizontal flange portion in the installed state. The lower reinforcing member is formed continuously with the lower main body portion, the lower main body portion being disposed in contact with the lower surface of the lower horizontal flange portion. It has a lower extension that extends from the end of the lower horizontal flange in the installed state,
The upper extension part and the lower extension part have an engaging part that engages with each other and restricts the lower extension part from moving downward, and the upper extension part and the lower extension part are engaged in an engaged state. A gap is formed on the opposing surface of the extending portion, and when the base portion of the upper horizontal flange and the lower horizontal flange is separated in the vertical direction, the gap is closed so that the opposing surface can contact. As a result, an appropriate fatigue strength can be improved by a simple jig that does not require a tightening member and does not require management of a tightening force or the like, and can be mounted without requiring many man-hours.
In addition, the gap is closed when the base portions of the upper horizontal flange and the lower horizontal flange are separated in the vertical direction so that the opposing surface can come into contact, so that the flange joint is reinforced until the gap is closed. No stress is applied to the jig.For example, when the wind load is small and the distance between the base of the upper horizontal flange and the lower horizontal flange is small, the stress is not applied to the flange joint reinforcement jig. Can prevent fatigue failure of the flange joint reinforcing jig.

It is explanatory drawing explaining the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention. It is explanatory drawing explaining the upper reinforcement member in the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention. It is explanatory drawing explaining the lower reinforcement member in the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention. It is explanatory drawing explaining the attachment method of the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention. It is explanatory drawing explaining the other aspect of the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention (the 1). It is explanatory drawing explaining the other aspect of the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention (the 2). It is explanatory drawing explaining the other aspect of the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention (the 3). It is explanatory drawing explaining the other aspect of the flange junction part reinforcement jig | tool which concerns on one embodiment of this invention (the 4). It is explanatory drawing of the wind power generation equipment mentioned as an example of the tower structure which flange-joined steel pipes. It is explanatory drawing explaining the bolt joint of the flange of the steel pipes which comprise the tower structure shown in FIG. It is explanatory drawing explaining the "lever reaction force" which acts when bolting the flange of steel pipes.

As shown in FIG. 1, a flange joint reinforcing jig 1 according to an embodiment of the present invention is provided at a lower horizontal flange portion 3 provided at an end portion of a lower steel pipe and an end portion of an upper steel pipe. The upper horizontal flange portion 5 is joined with a bolt and a nut (see FIG. 10) to reinforce the bolt joint portion in the tower structure in which the steel pipes are joined to each other, and the flange surface side of the upper horizontal flange portion 5 And the lower reinforcing member 9 disposed on the lower horizontal flange portion 3 side.
Examples of the tower structure in which the steel pipes are flange-joined include a bridge pier, a steel chimney, and the like in addition to the tower body of the wind power generation equipment described above.
Hereinafter, details of the upper reinforcing member 7 and the lower reinforcing member 9 will be described.

<Upper reinforcement member>
The upper reinforcing member 7 is formed by pressing and bending a thick plate-like member, and as shown in FIG. 2, the upper main body extends from the base side of the upper horizontal flange portion 5 toward the flange end portion. Part 11 and upper extension part 13 which is formed continuously from upper body part 11 and extends from the end of upper horizontal flange part 5 in the installed state (see FIG. 1).
As shown in FIG. 2, the upper main body 11 has a rectangular plate shape. The upper main body 11 is formed with two openings 15 into which the bolt heads can be inserted.
The upper extension part 13 has a substantially rectangular shape that is bent downward continuously from the upper body part 11. The upper extending portion 13 is provided with a substantially T-shaped locking hole 17 in which a locking portion 25 of the lower extending portion 21 described later can be engaged.

  In the case of a large-scale wind power generation facility, the bolt diameter is 30 to 50 mm, the flange width of the upper horizontal flange portion 5 and the lower horizontal flange portion 3 is 2 to 4 times the bolt diameter, and the upper horizontal flange portion 5 and the lower horizontal flange portion 3 are Since the stacked thickness is about 200 mm, it is preferable to use a reinforcing member having a cross section of the same thickness.

<Lower reinforcing member>
As shown in FIG. 3, the lower reinforcing member 9 is formed continuously from the lower main body portion 19 extending from the base side of the lower horizontal flange portion 3 toward the flange end portion, and the lower main body portion 19. 1 has a lower extension 21 extending from the end of the lower horizontal flange 3.
As shown in FIG. 3, the lower main body 19 has a substantially rectangular shape, and a notch 23 into which a nut can be inserted is formed on the base side.
The lower extension part 21 has a substantially T-shaped locking part 25 formed upward from the lower main body part 19.
The engaging hole 26 and the engaging portion 25 constitute the engaging portion 26 of the present invention.

<Mounting method>
A method of attaching the flange joint reinforcing jig 1 according to the present embodiment configured as described above will be described with reference to FIG.
The head of the bolt (see FIG. 10) that joins the flange joint is inserted into the opening 15 and the upper reinforcing member 7 is placed on the upper horizontal flange 5 with the upper extension 13 facing downward (see FIG. 10). (See FIG. 4 (a)).
The lower reinforcing member 9 is arranged so that the lower extension portion 21 faces upward and the lower main body portion 19 is horizontal to the lower horizontal flange portion 3, and in this state, moves to the base side of the lower horizontal flange portion 3. (See FIG. 4B), the lower reinforcing member 9 is further moved to lock the lower extension 21 in a state in which the nut (see FIG. 10) can be inserted into the notch 23 of the lower main body 19. The part 25 is inserted into the locking hole 17 of the upper extension part 13 (see FIG. 1).
As a result, the locking portion 25 of the lower extension portion 21 is engaged with the locking hole 17 of the upper extension portion 13, and the lower reinforcing member 9 is held by the upper reinforcing member 7.
At this time, a gap 27 is formed between the opposing surfaces of the upper extension 13 and the lower extension 21.

<Description of action>
As shown in FIG. 11 (a), the upper horizontal flange portion 5 and the lower horizontal flange are acted upon by the “leverage principle” using the ends of the upper horizontal flange portion 5 and the lower horizontal flange portion 3 as fulcrums, as shown in FIG. The part 3 is deformed, and the bases of the upper horizontal flange part 5 and the lower horizontal flange part 3 are opened. When the base portion is opened, the base portion side of the upper main body portion 11 of the upper reinforcing member 7 is lifted, and conversely, the base portion side of the lower main body portion 19 of the lower reinforcing member 9 is pushed down. As a result, the upper extending portion 13 of the upper reinforcing member 7 is pushed. And the lower extending portion 21 of the lower reinforcing member 9 approach each other, and the gap distance of the gap 27 is reduced.
However, in a state where the opening amount is small, no stress acts on the flange joint reinforcing jig 1 simply by reducing the gap distance of the gap 27.
In this way, when the wind load is small, no stress acts on the flange joint reinforcing jig 1 and stress acts only on the bolt. Therefore, no stress acts on the flange joint reinforcing jig 1 at all times. Fatigue failure of the flange joint reinforcing jig 1 can be prevented.

When the wind load increases and the opening amount increases, the upper extension 13 of the upper reinforcement member 7 and the lower extension 21 of the lower reinforcement member 9 approach each other and the gap 27 is closed. The opposing surfaces of the lower extension 21 abut against each other to transmit the compressive force.
When the upper extension portion 13 and the lower extension portion 21 transmit the compressive force, the tensile stress acting on the bolt is relaxed, and the fatigue strength of the bolt can be improved.

  Further, in the present embodiment, it is possible to improve the fatigue strength of the flange joint without modifying the existing flange portion, and it is not necessary to redesign the entire flange or reselect the bolt. In addition, the fatigue strength of the flange joint can be improved.

In the flange joint reinforcement jig 1 according to the present embodiment, when the tensile stress acts on the bolt by adjusting the gap 27 between the opposing surfaces of the upper extension 13 and the lower extension 21. Whether the stress acts on the flange joint reinforcing jig 1 can be adjusted.
That is, if the gap distance of the gap 27 is small, the compressive stress acts on the flange joint reinforcing jig 1 from the state where the tensile stress acting on the bolt is small. Conversely, if the gap distance of the gap 27 is large, the tensile stress acting on the bolt. Compressive stress acts on the flange joint reinforcing jig 1 from a state in which is increased to some extent.
As to how to set the gap 27, for example, when the bolt is deformed by 50% of the deformation amount of the elastic limit, the gap distance becomes zero, and stress is applied to the flange joint reinforcing jig 1. It is preferable to set it to work.
In the present embodiment, various fatigue strengths can be realized by setting the gap distance of the gap 27.

  The gap 27 can be easily adjusted by adjusting the lengths of the upper body portion 11 and the lower body portion 19 in the flange width direction.

Further, in the conventional method disclosed in Patent Document 1, (a) production and design of a reinforcing member and a fastening member, (b) attachment of the reinforcing member and the fastening member, and (c) fastening force of the fastening member. And (d) confirmation of tightening force is required.
On the other hand, in the present invention, the fatigue strength of the flange joint can be improved only by the steps of (a) production / design of the flange joint reinforcement jig and (b) attachment of the flange joint reinforcement jig. There is an effect that man-hours can be reduced as compared with the conventional method.
Further, since no tightening member is required, man-hours can be reduced, and management of the tightening force is not required, thereby enabling extremely simple attachment.

  When the wind direction is specified and the stress concentration is biased as in a wind power generation facility, it is considered that fatigue failure will occur again at the same location just by replacing the damaged bolt with a new bolt. In the flange joint reinforcement jig according to the present embodiment, it is possible to improve the fatigue strength more easily. Therefore, by installing the flange joint reinforcement jig according to the present invention together with the installation of a new bolt, The occurrence of fatigue failure at the same location can be prevented.

  In addition, the flange joint reinforcing jig of the present embodiment can be reasonably reinforced in accordance with the range of the damaged portion, and in particular, the wind power generation equipment has a structure that uses a plurality of bolts as its size increases. However, local reinforcement using the flange joint reinforcement jig of the present embodiment is a very effective reinforcement method.

  In the above-described embodiment, an example in which two bolts are reinforced is shown. However, the number of bolts to be reinforced is arbitrary, and the openings 15 and the notches 23 are formed according to the number of bolts to be reinforced. Set the number.

In the above description, as the shape of the engaging portion 26, the upper extending portion 13 is provided with the substantially T-shaped opening locking hole 17, and the lower extending portion 21 can be inserted into the locking hole 17. Although the substantially T-shaped member locking portion 25 has been exemplified, the present invention is not limited to this, and can take various forms.
For example, as shown in FIG. 5, the shape of the locking hole 17 formed in the upper extension portion 13 is a tapered hole that becomes narrower downward, and the locking portion 25 formed in the lower extension portion 21. The trapezoidal shape can be inserted into the locking hole 17.
Moreover, as shown in FIG. 6, it is good also considering the upper extension part 13 as a reverse L-shape and the L-shape where the lower extension part 21 was inverted.
Further, as shown in FIG. 7, a plurality of locking holes 17 and locking portions 25 constituting the engaging portion 26 may be provided.

In the above description, the upper body 11 of the upper extension 13 is provided with the opening 15 into which the bolt head can be inserted, and the lower body 19 of the lower extension 21 is provided with the notch 23. However, as shown in FIG. 8, a notch 23 into which the bolt head portion can be inserted is provided in the upper main body portion 11 of the upper reinforcing member 7, and an opening portion in which a nut can be inserted into the lower main body portion 19 of the lower reinforcing member 9. You may make it provide a notch part.
Of the upper reinforcing member 7 and the lower reinforcing member 9, the one provided with the notch 23 is attached later.

In the above description, the case where the upper reinforcing member 7 is formed by pressing and bending is described. However, the method of forming the upper reinforcing member 7 is not limited to this, and a grooved steel or an angle steel is used. You may form by a punching process or a cutting process.
Similarly, the lower reinforcing member 9 may be formed by a punching process, a punching process, a cutting process, or the like using a push-bending process or a channel steel or an angle steel.

DESCRIPTION OF SYMBOLS 1 Flange joint part reinforcement jig | tool 3 Lower horizontal flange part 5 Upper horizontal flange part 7 Upper reinforcement member 9 Lower reinforcement member 11 Upper main body part 13 Upper extension part 15 Opening part 17 Locking hole 19 Lower main body part 21 Lower extension part 23 Notch portion 25 Locking portion 26 Engaging portion 27 Clearance 29 Wind power generation equipment 31 Tower 33 Blade 35 Bolt 37 Nut

Claims (3)

A flange in a tower structure in which a lower horizontal flange portion provided at an end portion of a lower steel pipe and an upper horizontal flange portion provided at an end portion of an upper steel pipe are joined by bolts and nuts to join the steel pipes together. A flange joint reinforcing jig for reinforcing the joint,
An upper reinforcing member disposed on the flange surface side of the upper horizontal flange portion , and a lower reinforcing member disposed on the lower horizontal flange portion side,
The upper reinforcing member is formed on the upper surface of the upper horizontal flange portion, and is continuously formed on the upper body portion and extends from the end of the upper horizontal flange portion in the installed state. Having an upper extension,
The lower reinforcing member includes a lower main body portion disposed at least partially in contact with a lower surface of the lower horizontal flange portion, and an end of the lower horizontal flange portion formed in an installed state continuously with the lower main body portion. Having a lower extension extending beyond the part,
The upper extension part and the lower extension part have an engaging part that engages with each other and restricts the lower extension part from moving downward, and the upper extension part and the lower extension part are engaged in an engaged state. A gap is formed on the opposing surface of the extending portion, and when the base portion of the upper horizontal flange portion and the lower horizontal flange portion are separated in the vertical direction, the gap is closed and the opposing surface can come into contact. A flange joint reinforcing jig characterized by the above.   The upper reinforcing member is provided with a hole or notch into which a bolt head of the bolt can be inserted, and the lower reinforcing member is provided with a notch into which the nut can be inserted. Item 2. The flange joint reinforcing jig according to Item 1.   The upper reinforcing member is provided with a notch into which a bolt head of the bolt can be inserted, and the lower reinforcing member is provided with a hole or notch into which the nut can be inserted. Item 2. The flange joint reinforcing jig according to Item 1.