JP2014080825A - Pipe fastening structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe fastening structure which can sufficiently receive a twisting force and a shear force, applied to a fastening part between pipes, by an engaging body.SOLUTION: A pipe fastening structure includes: a first fastener 2 which is an annular member attached to facing fastening ends of two pipes and is formed with recessed parts 6 and recessed grooves 23 in the upper surface thereof; a second fastener which is disposed inside the first fastener 2 and whose outer peripheral surface is in contact with the inner peripheral surface of the first fastener 2 and formed with a bolt through hole; a bolt which is inserted into a through hole, formed by fitting the recessed grooves 23 to each other in a state where the first fasteners 2 abut on each other, from the inside of the second fastener through the bolt through hole; and an engaging body 5 which is arranged in a storage space formed by fitting the recessed parts 6 to each other in a state where the first fasteners 2, attached to both fastening ends, abut on each other. The engaging body 5 is formed in a polygonal column shape, and the inner peripheral surface of the recessed part 6 is formed in a polyhedron corresponding to the outer peripheral surface of the engaging body 5.

Description

  The present invention relates to a pipe fastening structure that is used for a pipe fastening body that is driven mainly for the strengthening of ground at a construction site or a civil engineering site.

In a construction site or civil engineering site, in order to strengthen the ground, etc., a pipe fastening body constituted by arranging a plurality of pipes along the longitudinal direction and fastening ends of adjacent pipes may be embedded in the ground. . When the pipe fastening body is embedded in the ground, the pipe fastening body is screwed into the ground or the pipe fastening body is driven, and at this time, a large torsional force and shearing force are applied to the fastening portions of the pipes. As a pipe fastening structure that is durable against this large torsional force and shearing force, the applicant has previously disclosed what is shown in Patent Document 1.
In this case, an annular first fastener is attached to the lower end surface of the upper pipe and the upper end surface of the lower pipe, respectively, and an arc-shaped second fastener is provided inside both fasteners. A concave groove having a semicircular cross section is provided along the radial direction of the first fastener on the end face of the first fastener that abuts each other, and the concave groove is formed in a state where both the first fasteners are abutted. Together, a through hole is formed. A bolt is passed from the inside of the second fastener to the second fastener and the through hole, and a nut is screwed onto the tip of the bolt. The second fastener and the first fasteners are fastened by the bolt head and the nut. The torsional force and the shearing force applied to the fastening points of the pipes are received by the bolts.
A substantially circular recess is also formed in the end surface of the first fasteners that face each other in plan view. The recess opens to the outer peripheral surface of the first fastener. The storage space is formed by combining the recesses in a state where both the first fasteners are in contact with each other. A cylindrical engaging body is disposed in the storage space, and the torsional force and shearing force applied to the fastening portions of the pipes are also received by the engaging body. That is, the torsional force and shearing force applied to the fastening portions of the pipes are received by the bolt and the engaging body.

JP 2007-77695 A

In the conventional configuration, the engaging body is cylindrical and the recess is circular in plan view. However, in order to fit the engaging body into the recess, a gap is formed between the inner peripheral surface of the recess and the outer peripheral surface of the engaging body. It is necessary to provide it. Therefore, due to this gap, the engaging body is actually in line contact or point contact with the inner peripheral surface of the recess. In this case, the engagement body cannot sufficiently receive the torsional force and shearing force applied to the fastening portion between the pipes.
Further, as a result of the engaging body receiving a torsional force and a shearing force, an outward force along the radial direction of the pipe may be applied to the engaging body. In this case, there is a possibility that the engaging body may fall outward from the opening on the outer peripheral surface of the first fastener. In this case, the engaging body is buried in the ground, making it difficult to search.
An object of the present invention is to sufficiently receive a torsional force and a shearing force applied to a fastening portion between pipes by an engaging body. It is another object of the present invention to prevent the engagement body from dropping outwardly from the opening on the outer peripheral surface of the first fastener.

The pipe fastening structure is an annular member attached to each fastening end facing each other on two pipes arranged along the longitudinal direction, and a concave portion and a concave groove are formed on the upper surface so as to be separated from each other. A first fastener;
The first fastener is disposed inside the first fastener, and at least a part of the outer peripheral surface is in contact with the inner peripheral surface of the first fastener, and a bolt through hole penetrating the outer peripheral surface and the inner peripheral surface is provided. Two fasteners;
In the state where the first fasteners attached to both fastening ends are abutted with each other, the bolt through-holes are formed from the inside of the second fasteners into the through-holes formed by joining the concave grooves. With bolts inserted through,
In the state where the first fasteners attached to both fastening ends are in abutment with each other, the engagement body is disposed in a storage space formed by combining the recesses,
The engaging body has at least one flat surface on its side surface, and the inner peripheral surface of the concave portion is formed to have a flat surface corresponding to the outer peripheral surface of the engaging body, and the flat surface of the engaging body is the inner surface of the concave portion. Touch the circumference.
The recess is formed across the inner and outer peripheral surfaces of the first fastener to form an opening in the inner and outer peripheral surface of the first fastener, and the outer peripheral surface of the engagement body is partially in the first It protrudes to the opening of the outer peripheral surface of 1 fastener, and the center of the said engaging body is located inside the intermediate surface of the outer peripheral surface of the said 1st fastener, and an internal peripheral surface.

1. The engaging body is formed so that the outer peripheral surface has at least one flat surface, and the inner peripheral surface of the recess is formed so as to have a flat surface corresponding to the outer peripheral surface of the engaging body. Surface contact with the peripheral surface. As a result, the torsional force and the shearing force applied to the fastening portion between the pipes can be sufficiently received by the engaging body.
2. The outer peripheral surface of the engaging body protrudes from the opening of the outer peripheral surface of the first fastener, and the center of the engaging body is positioned on the inner side of the intermediate surface between the outer peripheral surface of the first fastener and the outer peripheral surface. Thus, the opening can be reduced. Thereby, it is possible to prevent the engagement body from dropping out of the first fastener from the opening.

It is a side view which shows a pipe fastening structure. It is sectional drawing which fractured | ruptured FIG. It is a perspective view of a 1st fastener. It is a perspective view of a 2nd fastener. FIG. 3 is a cross-sectional view of FIG. It is explanatory drawing of the fastening procedure of the 1st fasteners. It is an enlarged plan view of the engaging body fitted in the first fastener.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view showing a pipe fastening structure, and FIG. 2 is a cross-sectional view taken along the line II of FIG. 1 taken along the line II. In the present embodiment, the pipe fastening structure is described as a structure in which pipes adjacent in the vertical direction are connected, but the same structure is also effective in connecting pipes adjacent in the horizontal direction.
As shown in FIG. 1, a first fastener 2 is fixed to a fastening side end portion, that is, a lower end portion of the upper pipe A by a welded portion 10. The upper pipe A and the first fastener 2 are both made of metal, and a weld 10 is formed between the upper pipe A and the first fastener 2 in advance in a factory or the like. Further, the first fastener 2 having the physically same structure is fixed to the fastening side end portion, that is, the upper end portion of the lower pipe B by the welded portion 10. The lower pipe B is also made of the same metal as the upper pipe A.

As shown in FIG. 2, the first fastener 2 has an annular shape, and a plurality of arc-shaped second fasteners 3 are arranged inside the first fastener 2. The first fastener 2 and the second fastener 3 are fastened by screwing a nut 40 to the tip of a bolt 4 inserted from the inside of the second fastener 3. As will be described later, four second fasteners 3 are arranged at equal intervals along the circumferential direction of the first fastener 2, but only two are shown in FIG. 2 for convenience of illustration.
FIG. 3 is a perspective view of the first fastener 2. The first fastener 2 is integrally formed with a first ring 20 positioned at the upper part and a second ring 21 positioned below the first ring 20 and having a large inner diameter. That is, the first ring 20 has an annular protrusion 26 that protrudes inward as compared with the second ring 21.

  The first ring 20 of the first fastener 2 is formed with a recess 6 on the upper surface and a recess groove 23 extending radially from the outer peripheral surface of the first fastener 2 toward the inner peripheral surface. doing. Two recesses 6 are formed so as to be symmetric with respect to the center point C (see FIG. 2) of the first fastener 2, and the recesses 23 are spaced apart from each other by 90 ° about the center point C. One is formed. In addition, the number of the recessed parts 6 and the recessed grooves 23 is not limited to this.

  The recess 6 is formed across the inner and outer peripheral surfaces of the first fastener 2 and forms an opening in the inner and outer peripheral surfaces. That is, the outer opening 60 is formed on the outer peripheral surface of the first fastener 2, and the inner opening 61 is opened on the inner peripheral surface. A polygonal prism-like engagement body 5 is fitted in the recess 6, and a hexagonal prism-like engagement body 5 in FIG. 3, and the recess 6 has a side face corresponding to the outer peripheral surface of the engagement body 5. Specifically, the side surfaces of the recess 6 are formed to extend inward from each other from the outer opening 60 and from the inner opening 61 to extend outward from each other and continue to the first surface 62. The second surface 63 is integrally provided.

FIG. 4 is a perspective view of the second fastener 3. The second fastener 3 is formed by integrally forming a vertical wall piece 30 and a pair of horizontal pieces 31 extending horizontally from the upper and lower ends of the wall piece 30 toward the first fastener 2. Yes. A fitting space 32 is formed between the horizontal pieces 31.
A bolt through hole 33 through which the bolt 4 passes is formed in the wall piece 30, and a head portion 42 of the bolt 4 is in contact with the inner peripheral surface of the wall piece 30. A washer 41 is fitted to the tip of the bolt 4 and the nut 40 is screwed as described above.

  FIG. 5 is a cross-sectional view of FIG. 2 taken along the line II-II and viewed from the direction of the arrow. Both the first fasteners 2 are arranged so that the concave portions 6 and the concave grooves 23 face each other, and in a state where the first fasteners 2 are abutted, the two concave grooves 23 are joined together. A through-hole 22 through which the bolt 4 is passed is formed. Further, the protrusions 26 are combined to form the fitting protrusion 25. That is, the through hole 22 is located inside the fitting protrusion 25. The fitting protrusion 25 forms a tapered surface so that the circumferential surface is reduced in diameter toward the tip. The outer peripheral surface of the fitting protrusion 25 is fitted in the fitting space 32 of the second fastener 3. That is, the second fastener 3 is provided according to the position of the concave groove 23, and only two second fasteners 3 are shown in FIG. 2, but originally according to the number of the concave grooves 23, Four are provided. Further, if the vertical dimension of the base end portion of the fitting protrusion 25 is formed to be slightly larger than the vertical width of the fitting space 32, the fitting protrusion 25 can be tightly fitted in the fitting space 32 like a wedge. .

On the other hand, as shown in FIG. 1, in the state where both the first fasteners 2 are abutted, the two recesses 6 are combined to form a storage space 64 for storing the engaging body 5. Since a part of the outer peripheral surface of the engagement body 5 can be seen from the outer opening 60, it can be easily confirmed whether the engagement body 5 is stored in the storage space 64.
The first fasteners 2 are abutted and fastened by the second fastener 3. As a result, the upper pipe A and the lower pipe B are fastened to form the pipe fastening body 11.
As in the prior art, when the pipe fastening body 11 is embedded in the ground, the pipe fastening body 11 is screwed into the ground or the pipe fastening body 11 is driven. At this time, a large torsional force and shearing force are applied to the fastening portion between the first fasteners 2. This torsional force and shearing force are received by the bolt 4 and the engagement body 5.

(Fastening procedure between first fasteners)
The first fastener 2 and the second fastener 3 configured as described above are fixed to the end surfaces of the pipes A and B to be fastened in advance at a factory or the like by welding. The first fasteners 2 of both pipes A and B can be fixed as follows.
As shown in FIG. 6, first, the engaging body 5 is inserted into the recess 6 of the first fastener 2 fixed to the end surface of the lower pipe B. Next, the 2nd fastener 3 which penetrated the volt | bolt 4 is prepared, the washer 41 is fitted to the volt | bolt 4, and the nut 40 is screwed together by the front-end | tip part of this volt | bolt 4. In this state, the bolt 4 is placed in the concave groove 23 and the nut 40 is pushed inward to bring the washer 41 into contact with the outer peripheral surface of the first fastener 2. The second fastener 3 is separated from the inner peripheral surface of the first fastener 2 and can be moved outward by the rotation of the nut 40.

  Next, the first fastener 2 fixed to the end surface of the upper pipe A is overlapped with the first fastener 2 on the lower pipe B so that the concave portions 6 and the concave grooves 23 are aligned with each other. A storage space 64 in which the recesses 6 are combined to store the engaging body 5 is formed, and a bolt through hole 33 through which the bolt 4 passes is formed by combining the recess grooves 23. When the nut 40 is tightened in this state, the second fastener 3 moves toward the first fastener 2. The fitting space 32 of the second fastener 3 is fitted into the fitting protrusion 25 of the first fastener 2 and the first fasteners 2 are fixed. When the nut 40 is further tightened, both the first fastener 2 and the second fastener 3 are firmly fastened by the head portion 42 of the bolt 4, the nut 40 and the washer 41, and the pipe fastening body 11 is completed. To do. Note that the engaging body 5 may be inserted into the recessed portion 6 after the bolt 4 is placed in the recessed groove 23.

FIG. 7 is an enlarged plan view of the engagement body 5 fitted in the first fastener 2. In FIG. 7, a virtual surface located between the outer peripheral surface and the inner peripheral surface of the first fastener 2 is defined as an intermediate surface T, and the center of the engagement body 5 is defined as C1. In FIG. 7, the center C <b> 1 of the engagement body 5 is located inside the intermediate surface T. As a result, the area of the outer opening 60 of the first fastener 2 is reduced, and when the pipe fastening body 11 is embedded in the ground, the engagement body 5 can be applied even if a twisting force or a shearing force is applied to the fastening portion between the pipes. This prevents the first fastener 2 from falling outward.
Further, the outer peripheral surface of the engaging body 5 is formed in a hexagonal shape, and the inner peripheral surface of the recess 6 is formed as a polyhedron in which the first surface 62 and the second surface 63 are connected to correspond to the outer peripheral surface of the engaging body 5. Therefore, the engaging body 5 comes into surface contact with the first surface 62 and the second surface 63 of the recess 6. Thereby, the torsional force and shearing force which are applied to the fastening part of the pipes by the engaging body 5 can be sufficiently received.

  Furthermore, since the center C <b> 1 of the engagement body 5 is located on the inner side of the intermediate surface T, the boundary line between the first surface 62 and the second surface 63 is also located on the inner side of the intermediate surface T. Accordingly, the first surface 62 formed obliquely inward has a larger area than the second surface 63 formed obliquely outward. For this reason, as shown in FIG. 7, even if a torsional force or a shearing force is applied to the first fastener 2 and the same stress is applied to the first surface 62 and the second surface 63, the first surface 62 causes the engaging body 5 to be engaged. The force F <b> 1 applied to is greater than the force F <b> 2 applied to the engagement body 5 by the second surface 63. Therefore, the engagement body 5 is biased inward. This also prevents the engagement body 5 from falling off the first fastener 2 outwardly.

In the above description, the engaging body 5 is a hexagonal column. In response to this, the recess 6 may have a flat surface in contact with the flat surface of the engagement body 5.
Moreover, although the 1st fastener 2 and the 2nd fastener 3 are using what was manufactured by forging, it may be a casting product or what was manufactured by machining. Further, the engagement body 5 is often manufactured from carbon steel having high mechanical strength, but may be manufactured from tool steel, stainless steel, or other alloys.

  The pipe fastening structure according to the present invention is effective when used for a pipe fastening body that is driven to strengthen the ground at a construction site or a civil engineering site.

2 First fastener 3 Second fastener 4 Bolt 5 Engagement body 6 Recess

Claims (5)

1st fastening which is an annular member attached to each fastening end part which mutually opposes on two pipes arranged along a longitudinal direction, and a crevice and a ditch are formed in the upper surface apart from each other Ingredients,
The first fastener is disposed inside the first fastener, and at least a part of the outer peripheral surface is in contact with the inner peripheral surface of the first fastener, and a bolt through hole penetrating the outer peripheral surface and the inner peripheral surface is provided. Two fasteners;
In the state where the first fasteners attached to both fastening ends are abutted with each other, the bolt through-holes are formed from the inside of the second fasteners into the through-holes formed by joining the concave grooves. With bolts inserted through,
In the state where the first fasteners attached to both fastening ends are in abutment with each other, the engagement body is disposed in a storage space formed by combining the recesses,
The engaging body has at least one flat surface on its side surface, and the inner peripheral surface of the concave portion is formed to have a flat surface corresponding to the outer peripheral surface of the engaging body, and the flat surface of the engaging body is the inner surface of the concave portion. Pipe fastening structure in contact with the peripheral surface.   The recess is formed across the inner and outer peripheral surfaces of the first fastener to form an opening in the inner and outer peripheral surface of the first fastener, and a part of the outer peripheral surface of the engaging body is the first 2. The pipe fastening structure according to claim 1, wherein the pipe fastening structure projects to an opening on an outer peripheral surface of the fastener, and a center of the engaging body is located on an inner side of an intermediate surface between the outer peripheral surface and the inner peripheral surface of the first fastener. The recess is formed across the inner and outer peripheral surfaces of the first fastener, forming an opening on the inner and outer peripheral surface of the first fastener,
The openings formed on the inner and outer peripheral surfaces of the first fastener are an outer opening that is an opening on the outer peripheral surface of the first fastener and an inner opening that is an opening on the inner peripheral surface of the first fastener. And
A side surface of the recess includes a first surface extending inward so as to spread from the outer opening and a second surface extending outward from the inner opening and continuing to the first surface,
The pipe fastening structure according to claim 1, wherein the first surface has a larger area than the second surface.   The nut which fastens the 2nd fastener and both the 1st fasteners is screwing together with the tip part of the bolt which passed through the penetration hole between the heads of the bolt. The pipe fastening structure according to any one of 1 to 3. The both first fasteners are in a state of abutting each other, and a fitting protrusion is formed inside, and the second fastener forms a fitting space in which the fitting protrusion is fitted. The pipe fastening structure in any one of thru | or 4.

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