JP2020026654A - Flange joint and method of reinforcing flange joint - Google Patents

Abstract

To provide a flange joint in which a cover portion is not easily dropped even if boulders or the like flowing from an upstream collide.SOLUTION: A flange joint 1 comprises a first flange 2, a second flange 3 abutted and joined to the first flange 2, and a cover portion 4 formed integrally with the first flange 2 and covering at least a part of an outer peripheral portion 7a of a joint portion 7 of the first flange 2 and the second flange 3.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a flange joint and a method for reinforcing a flange joint.

  2. Description of the Related Art Conventionally, a catcher has been installed on a riverbed in order to catch boulders and the like flowing from an upstream of a river. This capturing body is formed by three-dimensionally constructing portions to be columns and beams by abutting flanged steel pipes, passing bolts through respective flange holes and fastening and joining nuts.

  In such a capturing body, a cover member covering the joint of the flange is attached to the joint of the flange in order to prevent the joint of the flange from being deformed by the impact of the boulder colliding with the flange. .

  As such a cover member, for example, a cover member described in Patent Document 1 is known. As shown in FIG. 19, the cover member of Patent Literature 1 includes two divided arc-shaped segments 201 and 202, and the two arc-shaped segments 201 and 202 are formed around the entire periphery of the joining portion 204 of the flange 203. Are attached to the joining portion 204 of the flange 203 by butt-joining and covering each other.

JP-A-2017-40074

  The above-mentioned cover member is used by being attached to the joint portion of the flange by joining two arc-shaped segments and joining them together, so that boulders and the like flowing from the upstream collide with the cover member and cover the cover member. If the member is damaged, the cover member may fall off from the joint of the flange.

  Therefore, the present invention has been made based on the above-described problem, and an object of the present invention is to provide a flange joint and a method of reinforcing a flange joint in which a cover portion is not easily dropped even when boulders or the like flowing from an upstream collide. To provide.

  A flange joint according to the present invention is formed integrally with a first flange, a second flange abutted on and joined to the first flange, and the first flange, the first flange and the second flange. And a cover portion that covers at least a part of the outer peripheral portion of the joining portion.

  According to this configuration, since the cover portion is formed integrally with the first flange, the cover portion is unlikely to fall off from the first flange even if boulders or the like collide with the cover portion and cause damage. Further, the cover portion covers at least a part of the outer peripheral portion of the joint portion between the first flange and the second flange. For this reason, if the cover is arranged facing upstream or upward, the boulder is prevented from directly colliding with the joint of the first and second flanges by the cover, and as a result, deformation of the joint is suppressed. Is done. Therefore, for example, when it is desired to replace only one of the steel pipes on which the first and second flanges are formed, the front surface of the first flange and the front surface of the second flange do not match, and the first and second flanges are firmly connected. Can be prevented from being joined.

  In the above configuration, the cover portion may be formed so as to cover a portion of the rear surface of the second flange opposite to the joining portion, which is less than half of the entire circumference in the circumferential direction.

  According to this configuration, the area covered by the cover portion in the second flange is increased, so that the boulder is prevented from directly colliding with the second flange. Therefore, it is possible to further suppress the deformation of the joint between the first and second flanges due to the collision of the boulders.

  Further, even if a force that separates the first and second flanges in the tube axis direction due to collision of boulders and the like acts on the first and second flanges, the first and second flanges are covered by the cover portion, so that the first and second flanges are covered. It becomes difficult for the second flange to be pulled apart in the pipe axis direction. Therefore, the durability of the joint between the first and second flanges is improved. Note that a gap may be formed between the back surface of the second flange and the cover. In this case, when a force that separates the first and second flanges in the pipe axis direction acts on the first and second flanges, a gap is formed in a gap large enough to allow the cover to contact the back surface of the second flange. .

  The said structure WHEREIN: The said flange joint may be provided with the joining tool which joins the said 1st flange and the said 2nd flange mutually. The joining tool may join the cover to the first flange and the second flange.

  According to this configuration, the cover portion is less likely to fall off the first and second flanges. Furthermore, since the cover is joined to the first and second flanges by using a joint for joining the first flange and the second flange to each other, it is necessary to prepare another joint for joining the cover. Absent. Furthermore, since the connector resists the force for separating the first and second flanges in the tube axis direction and the force in the direction perpendicular to the tube axis direction, the first and second flanges are less likely to be separated in the tube axis direction. Become.

  The said structure WHEREIN: The said cover part may be provided in the said back surface of the said 2nd flange so that it may cover several places spaced apart in the circumferential direction.

  According to this configuration, a plurality of portions on the back surface of the second flange can be locally protected by the cover as necessary.

  The said structure WHEREIN: The said cover part is formed so that the perimeter of the said outer peripheral part in the said junction part of a said 1st flange and a said 2nd flange may be covered, and a direction opposite to the said 1st flange from the said outer peripheral part. And protrude from the rear surface of the second flange. The flange joint may include a locking member that penetrates the cover portion in a radial direction from an outer peripheral side to an inner peripheral side and contacts the rear surface of the second flange.

  According to this configuration, since the cover portion is formed so as to cover the entire circumference of the outer peripheral portion in the joint portion between the first flange and the second flange, the joint portion between the first and second flanges. It is further suppressed that boulders collide directly with the boulder, and the deformation of the joint can be further suppressed. Further, the flange joint includes a locking member that penetrates the cover portion in the radial direction from the outer peripheral side to the inner peripheral side and contacts the rear surface of the second flange. For this reason, when boulders or the like collide with the cover portion or the steel pipe, even if a force that separates the first and second flanges in the pipe axis direction acts on the first and second flanges, the locking member responds to the force. The resistance makes it difficult for the first and second flanges to be pulled apart in the tube axis direction. Therefore, the durability of the joint between the first and second flanges is improved.

  The said structure WHEREIN: The said flange joint is provided integrally with the said 2nd flange, Comprising: The 2nd cover part which covers at least one part of the said outer peripheral part in the said junction part of a said 1st flange and a said 2nd flange is provided. You may. The second cover portion may be formed so as to cover a portion of the back surface of the first flange opposite to the joining portion, which is half or less of a full circumference in a circumferential direction.

  According to this configuration, the second cover portion is formed so as to cover less than half of the entire circumference in the circumferential direction on the back surface opposite to the joint portion of the first flange. It is further suppressed that the boulder directly collides with the joint of the two flanges. Further, since the second cover portion resists the force for separating the first and second flanges in the tube axis direction, the first and second flanges are less likely to be separated in the tube axis direction.

  In the method for reinforcing a flange joint according to the present invention, a cover portion is integrally formed with the first flange so as to cover at least a part of an outer peripheral portion of a joint portion between the first flange and the second flange joined to each other.

  According to this configuration, in the method of reinforcing the flange joint, the cover part is integrated with the first flange so as to cover at least a part of the outer peripheral part of the joint part of the first flange and the second flange joined together. Formed. Therefore, even if boulders or the like collide with the cover to cause damage, the cover does not easily fall off the first flange. Further, since the cover portion can be attached to the existing flange joint, the joint portion between the first and second flanges can be appropriately reinforced as necessary.

  ADVANTAGE OF THE INVENTION According to this invention, even if the boulders and the like flowing from the upstream collide, the cover portion does not easily fall off.

1 is a perspective view of a capturing body to which a flange joint according to a first embodiment of the present invention has been applied. It is a cross-sectional view showing the state where steel pipes were joined by the flange joint according to the first embodiment of the present invention. FIG. 3 is a sectional view taken along line III-III in FIG. 2. It is a cross-sectional view showing the state where steel pipes were joined by the flange joint according to the second embodiment of the present invention. It is sectional drawing cut | disconnected by the VV line of FIG. It is a figure showing the protection state by the cover part of the flange joint concerning a modification of a 2nd embodiment of the present invention. It is a cross-sectional view showing a state where steel pipes were joined by a flange joint according to a third embodiment of the present invention. It is sectional drawing cut | disconnected by the VIII-VIII line of FIG. It is a figure showing the protection state by the cover part of the flange joint concerning a modification of a 3rd embodiment of the present invention. It is a cross-sectional view showing a state where steel pipes were joined by a flange joint according to a fourth embodiment of the present invention. It is sectional drawing cut | disconnected by the XI-XI line of FIG. It is a cross-sectional view showing a state where steel pipes were joined by a flange joint according to a fifth embodiment of the present invention. It is sectional drawing cut | disconnected by the XIII-XIII line of FIG. It is a cross-sectional view showing a state where steel pipes were joined by a flange joint according to a sixth embodiment of the present invention. It is sectional drawing cut | disconnected by the XV-XV line of FIG. It is a perspective view of a reinforcement piece attached to a flange joint concerning a 7th embodiment of the present invention. It is a cross-sectional view showing a method of reinforcing a flange joint according to a seventh embodiment of the present invention. It is sectional drawing cut | disconnected by the XVIII-XVIII line of FIG. It is a perspective view which shows the attachment method of the cover member attached to the conventional flange joint.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, in the drawings referred to below, for convenience of description, the main components required for describing the flange joint according to the embodiment of the present invention are simplified. Therefore, the flange joint according to each embodiment of the present invention may include any component not shown in each drawing referred to in this specification.

(1st Embodiment)
Hereinafter, a capturing body 101 constructed by applying the flange joint 1 according to the first embodiment will be described with reference to FIGS. It should be noted that the flange joint 1 according to the present invention can be applied to any capturing body having a structure in which flanges are joined to connect steel pipes. In FIG. 1, a cover portion described later is omitted for simplification.

  The capturing body 101 includes a capturing unit 102 that captures boulders, driftwood, and the like flowing from the upstream of the river, a base unit (not shown) fixed to the riverbed to support and stabilize the weight of the capturing unit 102, Is provided.

  As shown in FIG. 1, the capturing portion 102 is formed by three-dimensionally constructing a portion to be a column or a beam. Specifically, the capturing unit 102 includes a plurality of pillars 103 erected on the foundation at intervals in a direction perpendicular to the flow direction of the river, and a plurality of supporting units 104 that support each pillar 103 from the downstream side. And a plurality of beams 105 bridged laterally with respect to the support pillar 103 and the support portion 104.

  Each support portion 104 has one end connected to the downstream surface at the upper end of the column 103 and the other end connected to a position away from the standing position of the column 103 in the base portion on the downstream side. , And support the pillar 103 so as not to fall down. The connection position of each support portion 104 with the column 103 is not limited to the upper end of the column 103, but may be a downstream surface in an intermediate portion between the upper end and the lower end of the column 103.

  Each beam 105 is bridged between each support 103 and each support 104. Each pillar 103, each support part 104, and each beam 105 are formed by connecting a plurality of steel pipes using the flange joint 1 of the first embodiment of the present invention.

  As shown in FIGS. 2 and 3, the flange joint 1 is formed at one end of a steel pipe 107 different from the steel pipe 106 at one end of the steel pipe 106 and is abutted against the first flange 2. The first flange 2 includes a second flange 3 to be joined, a joining tool 6 for joining the first flange 2 and the second flange 3 to each other, and a cover 4 formed integrally with the first flange 2.

  The first and second flanges 2 and 3 are each formed in a disk shape, and are fixed to one end of the steel pipes 106 and 107 so that their centers coincide with the center lines of the steel pipes 106 and 107. The first and second flanges 2, 3 have a diameter larger than the outer diameter of the steel pipes 106, 107 and protrude outward from the steel pipes 106, 107. The 1st and 2nd flanges 2 and 3 are joined by the joining tool 6 in the state which abutted on each other. Hereinafter, a portion where the front surface of the first flange 2 and the front surface of the second flange 3 abut against each other is referred to as a joint 7 between the first and second flanges 2 and 3.

  Note that the first and second flanges 2 and 3 may be formed in an annular shape having a circular through hole having the same diameter as the inner diameter of the steel pipes 106 and 107 as a center. That is, the first and second flanges 2 and 3 may be formed so as to protrude outward from the entire circumference of one end of the steel pipes 106 and 107 at right angles to the outer surfaces of the steel pipes 106 and 107. When the first and second flanges 2 and 3 are formed in an annular shape, the weight of the first and second flanges 2 and 3 is reduced as compared with the case where the first and second flanges 2 and 3 are formed in a disk shape. This leads to reduced work and material costs. Also, although the strength of the first and second flanges 2 and 3 is reduced as compared with the case where the first and second flanges 2 and 3 are formed in a disc shape, a part of the joint 7 between the first and second flanges 2 and 3 is As will be described later, since the first and second flanges 2 and 3 are formed in an annular shape, the strength can be compensated for because the first and second flanges 2 and 3 are covered with the cover portion 4.

  The connector 6 penetrates a substantially intermediate portion in the radial direction of the first and second flanges 2 and 3 in the pipe axis direction of the steel pipes 106 and 107. In addition, a plurality of the joints 6 are arranged at regular intervals in the circumferential direction at portions of the first and second flanges 2 and 3 protruding outward from the steel pipes 106 and 107. As the joining tool 6, for example, a bolt is used.

  The cover part 4 is formed on a part of the outer peripheral part 2 a of the first flange 2 in the circumferential direction. Specifically, the cover portion 4 is formed at a portion slightly shorter than half of the entire circumference of the outer peripheral portion 2a of the first flange 2 in the circumferential direction. Both side edges in the circumferential direction of the cover portion 4 extend parallel to the tube axis direction. The cover 4 may be formed over the entire circumference of the outer peripheral portion 2a of the first flange 2 in the circumferential direction.

  The cover portion 4 extends from the outer peripheral portion 2a of the first flange 2 to the outer peripheral portion 3a of the second flange 3 in the tube axis direction. That is, the cover portion 4 extends from the back surface 3a of the second flange 3 opposite to the joint portion 7 to a position where the cover portion 4 does not project in the tube axis direction. As a result, the cover portion 4 is brought into contact with a part of the outer peripheral portion 7 a of the joint portion 7 between the first and second flanges 2 and 3 and a part of the outer peripheral portion 3 a of the second flange 3, and 7 and a part of the outer peripheral portion 3a of the second flange 3 are covered from outside (see FIGS. 2 and 3). In the example of FIG. 2, the cover 4 extends to a position where the protruding end in the tube axis direction is flush with the back surface 3 a of the second flange 3. In addition, if the cover part 4 covers a part of the outer peripheral part 7a of the joint part 7 of the first and second flanges 2 and 3 and a part of the outer peripheral part 3a of the second flange 3 from outside, it is joined. The outer peripheral portion 7a of the portion 7 and the outer peripheral portion 3a of the second flange 3 do not need to be in contact with each other. Further, the cover portion 4 may protrude from the back surface 3a of the second flange 3 in the direction from the first flange 2 to the second flange 3 in the tube axis direction.

  The cover part 4 is formed integrally with the outer peripheral part 2 a of the first flange 2. Specifically, the cover portion 4 is integrally formed on the outer peripheral portion 2 a of the first flange 2 by welding a metal plate material different from the metal plate material forming the first flange 2. The cover 4 may be formed integrally with the outer peripheral portion 2a of the first flange 2 by using a connector such as a bolt. When the thickness of the cover portion 4 and the first flange 2 is small, the cover portion 4 is formed by bending a metal plate material for forming the first flange 2 and the cover portion 4 to form an outer peripheral portion of the first flange 2. 2a may be integrally formed.

  The flange joint 1 of the first embodiment configured as described above is used, for example, by abutting the first flange 2 and the second flange 3 in the tube axis direction. At this time, the first flange 2 and the second flange 3 are arranged such that the cover portion 4 covers a portion of the outer periphery 7a of the joint 7 between the first and second flanges 2 and 3 facing the upstream side. Joined. Regarding the flange joint 1 that joins the steel pipes 106 and 107 that form the beam 105 between the support 103 and the support 104, the cover 4 covers a part of the entire outer periphery 7 a of the joint 7 that faces upward. And used to join the first and second flanges 2,3.

  According to the flange joint 1 of the first embodiment, since the cover portion 4 is formed integrally with the first flange 2, even if the boulder or the like collides with the cover portion 4 and breaks, the cover portion 4 is not damaged. It is hard to fall off from the first flange 2.

  Further, since the boulder is suppressed by the cover portion 4 from directly colliding with the joint portion 7 between the first and second flanges 2 and 3, the deformation of the joint portion 7, that is, the front surface of the first flange 2 and The deformation of the front surface of the second flange 3 can be suppressed. Therefore, for example, when it is desired to replace only one of the plurality of steel pipes 106 and 107 forming the column 103, the front surface of the first flange 2 and the front surface of the second flange 3 do not match, and the first flange 2 is strongly fixed. 2 and the second flange 3 can be prevented from being unable to be joined.

  Furthermore, as for the cover part 4 covering the part facing the upstream side in the entire circumference of the outer peripheral part 7a of the joint part 7 between the first and second flanges 2, 3, boulders and the like flowing from the upstream are joined. Collision with the part 7 can be effectively suppressed. Further, for example, even if boulders collide with the steel pipe 106 from the upstream side, the cover portion 4 is in contact with the outer peripheral portion 3a of the second flange 3, so that the first flange 2 and the second flange 3 are in the pipe axial direction. Is prevented from being separated in a direction perpendicular to the direction. In addition, as for the cover part 4 which covers the part facing upward in the entire periphery of the outer peripheral part 7a of the joint part 7 between the first and second flanges 2, 3, the boulders are raised as in the case of increased water. From directly colliding with the joining portion 7 can be suppressed.

  The flange joint 1 of the first embodiment described above is an embodiment of the present invention, and the specific configuration thereof can be appropriately changed without departing from the spirit of the present invention.

(2nd Embodiment)
Hereinafter, the flange joint 21 of the second embodiment will be described. Elements corresponding to those of the flange joint 1 of the first embodiment are denoted by the same reference numerals as in the first embodiment, and description thereof is omitted.

  The flange joint 21 of the second embodiment is different from the first embodiment in that the cover 4 covers the back surface 3b of the second flange 3 on the side opposite to the joint 7. Specifically, as shown in FIGS. 4 and 5, the cover 4 includes a cover 5 extending in the pipe axis direction from the outer peripheral portion 2 a of the first flange 2, and a cover 5 extending in the radial direction from the cover 5 to the second flange 3. A locking piece 22 that protrudes inward and covers the back surface 3 b of the second flange 3.

  The cover piece 5 extends in a direction from the first flange 2 toward the second flange 3 in the pipe axis direction of the steel pipes 106 and 107 to a position protruding from the back surface 3 a of the second flange 3. As a result, the cover piece 5 is brought into contact with a part of the outer peripheral part 7a of the joint part 7 between the first and second flanges 2 and 3 and a part of the outer peripheral part 3a of the second flange 3, and 7 and a part of the outer peripheral portion 3a of the second flange 3 from outside. If the cover piece 5 covers a part of the outer peripheral part 7a of the joint part 7 and a part of the outer peripheral part 3a of the second flange 3 from outside, the outer peripheral part 7a of the joint part 7 and the second flange 3 It is not necessary to contact with the outer peripheral portion 3a of the main body. Both circumferential edges of the cover piece 5 extend parallel to the tube axis direction.

  The locking piece 22 is formed in an arc shape so as to be equal to or less than half of the entire circumference in a circumferential direction at a portion on the outer peripheral side of the back surface 3 b of the second flange 3. In the example of FIG. 5, the locking piece 22 is formed to be slightly shorter than half of the entire circumference in the circumferential direction on the outer peripheral side of the back surface 3 b of the second flange 3. The locking piece 22 extends from the cover piece 5 toward the inside of the second flange 3 in the radial direction to the vicinity of the connector 6. That is, the locking piece 22 is formed on the back surface 3 b of the second flange 2 so as not to protrude to the radial inside of the connector 6. The locking piece 22 is in contact with the back surface 3 b of the second flange 3. Note that the locking piece 22 may form a gap with the back surface 3b of the second flange 3 without contacting the back surface 3b of the second flange 3. In this case, when a boulder or the like collides with the steel pipes 106 and 107 and a force for separating the first flange 2 and the second flange 3 in the pipe axis direction acts on the first and second flanges 2 and 3, A gap is formed in such a size that the stop piece 22 can contact the back surface 3b of the second flange 3.

  The flange joint 21 of the second embodiment configured as described above is used as follows. First, the worker displaces the second flange 3 in a direction perpendicular to the tube axis direction with respect to the first flange 2 so that the second flange 3 does not contact the locking piece 22 of the cover portion 4, for example. Then, the second flange 3 and the first flange 2 are butted. Thereafter, the operator slides the second flange 3 in a direction orthogonal to the pipe axis direction to bring the locking piece 22 of the cover part 4 into contact with the back surface 3 a of the second flange 3. In this state, the operator joins the first and second flanges 2 and 3 with the joint 6.

  According to the flange joint 21 of the second embodiment, the cover 4 covers the cover 5 covering the outer peripheral portion 7 a of the joint 7 between the first and second flanges 2 and 3 and the back surface 3 b of the second flange 3. Since the locking flange 22 is provided, the area of the second flange 3 covered by the cover portion 4 is increased. Therefore, as compared with the first embodiment, the boulder directly colliding with the second flange 3 is further suppressed.

  Further, since the locking piece 22 is in contact with the back surface 3b of the second flange 3, a force for separating the first and second flanges 2, 3 in the tube axis direction acts on the first and second flanges 2, 3. However, the locking piece 22 resists this force. Therefore, the first and second flanges 2 and 3 are less likely to be separated in the tube axis direction, and the durability of the joint 7 between the first and second flanges 2 and 3 is improved.

  Note that a plurality of the cover portions 4 of the second embodiment may be arranged so as to cover a plurality of portions spaced apart in the circumferential direction at a portion that is less than half of the entire circumference on the outer peripheral side of the back surface 3b of the second flange 3. Good. In the example of FIG. 6, two cover parts 4 are provided. In this way, the cover 4 can locally protect the rear surface 3b of the second flange 3 and the outer peripheral portion 7a of the joint 7a of the first and second flanges 7 as needed.

(Third embodiment)
Next, a flange joint 31 according to a third embodiment will be described. The cover part 4 of the flange joint 31 of the third embodiment is different from the cover part of the second embodiment in that the locking piece 32 extends to the inside in the radial direction of the connector 6 as shown in FIGS. 4 is different. Elements corresponding to those of the flange joint 21 of the second embodiment are denoted by the same reference numerals as in the second embodiment, and description thereof will be omitted.

  The locking piece 32 is formed so as to have a length equal to or less than half of the entire circumference in the radially intermediate portion of the rear surface 3 b of the second flange 3. In the example of FIG. 8, the locking piece 32 is formed to be slightly shorter than half of the entire circumference in the radially intermediate portion of the rear surface 3 b of the second flange 3 in the radial direction. The locking piece 32 is joined to the first flange 2 and the second flange 3 by a joining tool 6 that joins the first flange 2 and the second flange 3 to each other. In the example of FIG. 7, the locking piece 32 is screwed together with a female screw formed on the inner surface of a through hole formed in the locking piece 32, the first flange 2, and the second flange 3 and a male screw of a bolt. It is joined to the first flange 2 and the second flange 3. Note that, without forming a female screw on the inner surface of the through hole, the locking piece 32 is joined to the first flange 2 and the second flange 3 by simply passing a bolt through the through hole and tightening the bolt with a nut. Is also good. A plurality of the joining tools 6 are arranged at regular intervals in the circumferential direction at a substantially middle portion in the radial direction of the back surface 3b of the second flange 3 (see FIG. 8).

  According to the flange joint 31 of the third embodiment, since the first flange 2 and the second flange 3 are joined to each other by the joining tool 6, the cover 4 falls off from the first and second flanges 2 and 3. It becomes difficult to do. Furthermore, since the cover part 4 is joined to the first and second flanges 2 and 3 using the joining tool 6 that joins the first flange 2 and the second flange 3 to each other, another cover for joining the cover part 4 is provided. There is no need to prepare a connector. Furthermore, since the joining tool 6 resists the force for separating the first and second flanges 2 and 3 in the tube axis direction and the force for separating the first and second flanges 2 and 3 in the direction orthogonal to the tube axis direction, the first and second flanges 2 and 3 are separated. Further, it is hard to be separated. Therefore, the durability of the joint 7 between the first and second flanges 2 and 3 is further improved.

  It should be noted that a plurality of the cover portions 4 of the third embodiment may be arranged so as to cover a plurality of spaced portions in a portion of the outer peripheral surface of the back surface 3b of the second flange 3 which is less than half of the entire circumferential direction. Good. In the example of FIG. 9, two cover portions 4 are provided. In this way, the cover 4 can locally protect the rear surface 3b of the second flange 3 and the outer peripheral portion 7a of the joint 7a of the first and second flanges 7 as needed.

(Fourth embodiment)
Next, a flange joint 41 according to a fourth embodiment will be described. As shown in FIGS. 10 and 11, the flange joint 41 is provided with a locking member 42, and the cover 4 covers the entire outer periphery 7 a of the joint 7 between the first and second flanges 2 and 3. The second embodiment differs from the first embodiment in that the cover portion 4 projects from the back surface 3b of the second flange 3. Elements corresponding to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and description thereof is omitted.

  The cover part 4 of the fourth embodiment is formed so as to cover the entire periphery of the outer peripheral part 7a in the joint part 7 between the first and second flanges 2, 3. The cover portion 4 is formed in a cylindrical shape so as to extend from the entire circumference of the outer peripheral portion 2 a of the first flange 2 in the direction from the first flange 2 to the second flange 3 in the tube axis direction. Thereby, the cover part 4 of the fourth embodiment covers the entire periphery of the outer peripheral part 7a of the joint part 7 between the first and second flanges 2, 3 from outside. In the example of FIG. 10, the cover part 4 of the fourth embodiment is in contact with the outer peripheral part 7 a of the joint 7 between the first and second flanges 2 and 3 and the outer peripheral part 3 a of the second flange 3. It is sufficient that at least the outer peripheral portion 7a and the outer peripheral portion 3a are covered. The cover part 4 of the fourth embodiment protrudes from the back surface 3b of the second flange 3 in the direction from the first flange 2 to the second flange 3 in the tube axis direction.

  The locking member 42 radially penetrates from the outer peripheral side to the inner peripheral side at a portion of the cover portion 4 protruding from the back surface 3 b of the second flange 3 in the tube axis direction, and comes into contact with the back surface 3 b of the second flange 3. ing. The plurality of locking members 42 are arranged at regular intervals in the circumferential direction (see FIG. 11). As the locking member 42, a metal bolt is used, but it is not limited to this. The locking member 42 has such a rigidity as to be able to resist a force that separates the first and second flanges 2 and 3 in the pipe axis direction, which can be generated when boulders and driftwood collide with the steel pipes 106 and 107 and the cover 4. For example, a rod-shaped member formed of wood or plastic may be used.

  According to the flange joint 41 of the fourth embodiment, the cover portion 4 is formed so as to cover the entire periphery of the outer peripheral portion 7a at the joint portion 7 between the first flange 2 and the second flange 3, so that each of the above-described embodiments is performed. Compared with the form, the boulder directly collides with the joint 7 between the first and second flanges 2 and 3 is further suppressed.

  According to the flange joint 41 of the fourth embodiment, the locking member 42 is in contact with the back surface 3b of the second flange 3. Therefore, when boulders and the like collide with the cover portion 4 and the steel pipes 106 and 107, even if a force that separates the first and second flanges 2 and 3 in the pipe axis direction acts on the first and second flanges 2 and 3. Since the locking member 42 resists the force, the first and second flanges 2 and 3 are less likely to be separated in the tube axis direction. Therefore, the durability of the joint 7 between the first and second flanges 2 and 3 is high.

(Fifth embodiment)
Next, a flange joint 51 according to a fifth embodiment will be described. The flange joint 51 of the fifth embodiment is different from the second embodiment in that the flange joint 51 further includes a second cover 52 as shown in FIGS. Elements corresponding to those in the second embodiment are denoted by the same reference numerals as in the second embodiment, and description thereof is omitted.

  The second cover portion 52 covers the outer side 7a of the joint 7 between the first and second flanges 2, 3 on the side opposite to the cover portion 4 with respect to the tube axis (see FIG. 12). The second cover portion 52 includes a cover 53 extending from a part of the outer periphery 3 a of the second flange 3 in the circumferential direction toward the outer periphery 2 a of the first flange 2, and a radius of the first flange 2 from the cover 53. And a locking piece 54 that protrudes inward in the direction and covers the back surface 2 b on the side opposite to the joint 7 of the first flange 2.

  The cover piece 53 of the second cover part 52 extends from the first flange 2 toward the second flange 3 in the pipe axis direction of the steel pipes 106 and 107 to a position protruding from the back surface 2a of the first flange 2. Thereby, the cover piece 53 of the second cover part 52 covers a part of the outer peripheral part 7a of the joint part 7 between the first and second flanges 2, 3 from outside. Both side edges in the circumferential direction of the cover piece 53 of the second cover part 52 extend in parallel with the pipe axis direction.

  As shown in FIG. 13, the locking piece 54 of the second cover part 52 is formed so as to cover less than half of the entire circumference in the circumferential direction on the outer peripheral side of the back surface 2 b of the first flange 2. In the example of FIG. 13, the circumferential lengths of the locking pieces 22 and 54 of the cover portion 4 and the second cover portion 52 are each half the circumferential length of the outer peripheral portion 2 a of the first flange 2. It is about one third.

  The flange joint 51 of the fifth embodiment configured as described above is used as follows. First, the worker, for example, to the extent that the second flange 3 does not contact the locking piece 22 of the cover part 4 and the first flange 2 does not contact the locking piece 54 of the second cover part 52. The second flange 3 and the first flange 2 are abutted against each other in a state where the second flange 3 is shifted from the first flange 2 in a direction orthogonal to the pipe axis direction. Thereafter, the operator slides the second flange 3 in a direction perpendicular to the pipe axis direction with respect to the first flange 2, thereby bringing the back surface 3 a of the second flange 3 into contact with the locking piece 22 of the cover portion 4. At the same time, the back surface 2 a of the first flange 2 is brought into contact with the locking piece 54 of the second cover part 52. In this state, the operator joins the first and second flanges 2 and 3 with the joint 6.

  By rotating the second flange 3 about the pipe axis together with the steel pipe 107, the second cover 52 is covered at the outer peripheral portion 7a of the joint 7 between the first and second flanges 2, 3. The first and second flanges 2 and 3 may be joined at a position adjacent to the portion 4 in the circumferential direction, and in this state.

  According to the flange joint 51 of the fifth embodiment, the second cover portion 52 is formed so as to cover a portion of the outer peripheral surface of the back surface 2b of the first flange 2 that is less than half of the entire circumference in the circumferential direction. Further, direct collision of boulders and the like with the joint 7 between the first and second flanges 2 and 3 is further suppressed. Furthermore, not only the locking piece 22 of the cover part 4 but also the locking piece 22 of the second cover part 52 resists the force separating the first and second flanges 2 and 3 in the tube axis direction. The first and second flanges 2, 3 are less likely to be separated in the tube axis direction than in the above embodiments.

  According to the flange joint 51 of the fifth embodiment, the second cover part 52 is formed on the outer peripheral part 7a of the joint part 7 between the first and second flanges 2 and 3 with the cover part 4 with respect to the pipe axis. It covers the other side. Therefore, even if a force that separates the first and second flanges 2 and 3 in the pipe axis direction acts on the first and second flanges 2 and 3, the locking piece 22 of the cover portion 4 and the second The locking piece 54 of the second cover part 52 can resist at a position symmetrical with respect to the tube axis. Therefore, the locking piece 22 of the cover part 4 and the locking piece 54 of the second cover part 52 can well-balanced resistance to the force separating the first and second flanges 2 and 3 in the tube axis direction. . As a result, the first and second flanges 2 and 3 are less likely to be separated in the tube axis direction.

(Sixth embodiment)
Next, a flange joint 61 according to a sixth embodiment will be described. As shown in FIGS. 14 and 15, the flange joint 61 of the sixth embodiment is such that the locking piece 62 extends to the inside of the joining tool 6 in the radial direction, and the cover part 4 and the second cover part 52 are joined. It differs from the fifth embodiment in that it is joined to the first and second flanges 2 and 3 by a tool 6. In other respects, the flange joint 61 of the sixth embodiment has the same configuration as the flange joint 51 of the fifth embodiment.

  According to the flange joint 61 of the sixth embodiment, the joining tool 6 resists the force of separating the first and second flanges 2 and 3 in the tube axis direction and the force of separating the first and second flanges 2 and 3 in the direction orthogonal to the tube axis direction. The first and second flanges 2, 3 are less likely to be separated than in the fifth embodiment. Therefore, the durability of the joint 7 between the first and second flanges 2 and 3 is higher than in the fifth embodiment.

(Seventh embodiment)
Next, a method of reinforcing the flange joint according to the seventh embodiment will be described. In each of the above embodiments, the cover portion 4 is integrally formed on the first flange 2 before installation. However, in the seventh embodiment, the cover portion 4 is formed on the existing first and second flanges 2 and 3 joined to each other. Are different from the above embodiments in that they are integrally formed.

  As shown in FIG. 16, the cover 4 of the seventh embodiment is configured such that a reinforcing piece 72 having substantially the same shape as that of the cover 4 of the third embodiment is attached to the existing first and second flanges 2 and 3. It is formed integrally. Therefore, elements corresponding to those in the third embodiment are denoted by the same reference numerals as in the third embodiment, and description thereof is omitted.

  The reinforcing piece 72 includes an arc-shaped cover piece 5 having an inner surface 5a formed along a part of the outer peripheral portions 2a, 3a of the first and second flanges 2, 3 of the existing flange joint in a circumferential direction; And an arc-shaped locking piece 32 extending at right angles to the cover piece 5 from the inner surface 5a of the piece 5. The locking piece 32 is formed over the entire length of one end of the cover piece 5 in the short direction. The locking piece 32 has a through hole 73 that allows the connector 6 to penetrate at a certain interval in the longitudinal direction.

  In the method of reinforcing a flange joint according to the seventh embodiment, a removing step of removing the joining tool 6 joining the first flange 2 and the second flange 3 of the existing flange joint, and a welding step of welding the reinforcing piece 72 And a joining step of joining the reinforcing pieces 72 with the joining tool 6 is performed.

  In the welding process, first, the operator firstly covers the outer peripheral portion 2a of the first flange 2 and the second flange 2 so as to cover a part of the outer peripheral portion 7a of the joint 7 between the first and second flanges 2 and 3. The inner surface 5a of the cover piece 5 of the reinforcing piece 72 is brought into contact with the outer peripheral portion 3a of the third piece 3. At the same time, the operator brings the locking piece 32 into contact with the back surface 3b of the second flange 3 (see the broken line in FIG. 16). In this state, the operator integrally forms both side edges in the longitudinal direction of the cover piece 5 and the outer peripheral portions 2a, 3a of the first and second flanges 2, 3 by welding.

  When the welding process is completed, a joining process is performed. In the joining step, the worker inserts the joining tool 6 from the through hole 73 of the engaging piece 32 and joins the engaging piece 32 to the first flange 2 and the second flange 3 as shown in FIG.

  Through the above steps, the cover part 4 is formed integrally with the first and second flanges 2 and 3 (see FIGS. 17 and 18).

  Note that the welding step may be performed before the joining step. One of the welding step and the joining step may be omitted.

  According to the method for reinforcing a flange joint of the seventh embodiment, in the welding step, a part of the outer peripheral portion 7a of the joint 7 of the existing first flange 2 and second flange 3 joined to each other is covered. The cover part 4 is integrally formed on the first and second flanges 2 and 3 by welding. Therefore, even if boulders or the like collide with the cover portion 4 to cause damage, the cover portion 4 is unlikely to fall off the first flange 2 and the second flange 3. Further, since the cover 4 can be attached to the existing flange joint, the joint 7 between the first and second flanges 2 and 3 can be appropriately reinforced as necessary.

  The plurality of reinforcing pieces 72 are attached to the first and second flanges 2 and 3 so that the entire periphery of the outer peripheral portion 7a of the joint 7 between the first and second flanges 2 and 3 is covered. Is also good.

DESCRIPTION OF SYMBOLS 1 Flange joint 2 1st flange 2a Back surface 3 2nd flange 3a Back surface 4 Cover part 6 Joiner 7 Joint part 7a Outer peripheral part 42 Locking member 52 Second cover part

Claims (7)

A first flange;
A second flange abutted against and joined to the first flange;
And a cover formed integrally with the first flange and covering at least a part of an outer peripheral portion of a joint between the first flange and the second flange.   2. The flange joint according to claim 1, wherein the cover portion is formed so as to cover a half or less of the entire circumference in a circumferential direction on a back surface of the second flange opposite to the joint portion. 3. A joint for joining the first flange and the second flange to each other,
The flange joint according to claim 2, wherein the connector joins the cover portion to the first flange and the second flange.   4. The flange joint according to claim 2, wherein the cover portion is provided so as to cover a plurality of circumferentially spaced portions on the back surface of the second flange. 5. The cover portion is formed so as to cover the entire periphery of the outer peripheral portion in the joint portion between the first flange and the second flange, and extends from the outer peripheral portion in a direction opposite to the first flange, and Projecting from the back surface of the second flange opposite to the joint,
The flange joint according to claim 1, further comprising a locking member that penetrates the cover portion in a radial direction from an outer peripheral side to an inner peripheral side, and that comes into contact with the rear surface of the second flange. A second cover portion formed integrally with the second flange and covering at least a part of the outer peripheral portion in the joint portion between the first flange and the second flange;
4. The flange according to claim 2, wherein the second cover portion is formed so as to cover a portion of the rear surface of the first flange opposite to the joining portion, which is half or less of a full circumference in a circumferential direction. 5. Fittings. A method of reinforcing a flange joint, wherein a cover portion is formed integrally with the first flange so as to cover at least a part of an outer peripheral portion of a joint portion between the first flange and the second flange joined to each other.