JPH083992A - Method for closing hole of pipe material and plug structure for pipe material - Google Patents

Abstract

PURPOSE:To firmly close a hole of a pipe material such as smooth sheath without complicating a constitution. CONSTITUTION:A skirt 12b of a plug body 12 is inserted into an injection hole (hole) 20 of a smooth sheath (pipe material) 18 and by tuning a screw 14, a nut (flange piece) is moved axially inwardly so that the nut is drawn into a recess 34 of the skirt. And by an elastic expansion of the diameter of the skirt 12b which is caused by the movement of the nut 16, the hole 20 of the smooth sheath is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe material, and more particularly to a pipe material hole closing method and a pipe material for closing an injection hole formed in a side surface of a smooth frame used for a permanent anchor. Regarding plug structure.

[0002]

2. Description of the Related Art For example, in a permanent anchor, it is necessary to secure reliability for a long period of time, and the durability of a tension material (usually PC stranded wire) is emphasized. Therefore, in the entire length of the fixing portion and the free length portion, that is, the entire length of the anchor length, for example, by coating with a corrugated sheath or a smooth sheath made of synthetic resin such as polyethylene, the PC steel strand is covered. Is isolated and protected.

For example, in a free length portion with respect to an anchor length fixed length portion fixed to the ground by pouring and solidifying grout (injection material), a stranded wire of PC steel (tensile material)
It is covered by a straight pipe-shaped smooth-sheath to isolate it from the grout. Then, rust preventive oil such as grease is filled around the PC steel wire inside the smooth-sheath to secure the expansion and contraction of the PC steel wire with respect to the smooth-sheath. -In the space
Generation of rust and corrosion of PC steel strands is prevented.

The rust-preventive oil is usually injected into the smooth space by a pump means such as a gear pump through a hole (injection hole) formed in the side surface. After the rust preventive oil is injected, the plug prevents the rust preventive oil from flowing out of the injection hole by closing the injection hole.

As a plug for closing the injection hole, a bolt having a corresponding diameter, a rubber plug, or the like is usually used, and the plug from the injection hole is pushed or fixed by taping after being inserted into the injection hole. Detachment is prevented.

[0006]

However, in the known construction, bolts, rubber plugs, etc. are inserted into the injection holes (holes) of the smooth frame (pipe material) and pressed down by taping. I'm just there. In other words, in order to reliably prevent the rust preventive oil from flowing out from the injection hole, it is necessary to maintain high dimensional accuracy in both the injection hole and the plug, so the work is likely to be complicated, and the reliability of clogging can be improved. The decline is inevitable.

Since the injection hole is formed in the curved surface which is the side surface of the smooth frame, the head of a flat bolt or the upper flange of a rubber plug is generally used as the injection hole. It becomes very difficult to make a close contact with the surroundings. That is, since it is not possible to easily close the gap by the head of the bolt or the like, it is unavoidable from this point as well that the reliability with respect to the closure is reduced.

Further, in the known construction, a tap such as a bolt or a rubber stopper must be pressed against the injection hole by taping. Therefore, the work is likely to be complicated,
Also in this respect, workability is reduced.

According to the present invention, the structure is not complicated.
An object of the present invention is to provide a pipe material hole closing method and a pipe material plug structure for surely closing a hole of a pipe material such as a smooth frame.

[0010]

To achieve this object, according to the method of closing a hole in a pipe material of the present invention, the skirt of the plug body extending below the flange is inserted into the hole of the pipe material. A flange piece having a diameter larger than the minimum diameter of the recess of the skirt is inserted and held in the recess of the skirt. And
The hole of the pipe material can be closed by elastically expanding the skirt diameter caused by the pulling in of the flange piece.

[0011]

In this construction, when the flange piece is pulled into the skirt recess, the diameter of the skirt elastically expands. Therefore, despite the simple construction, the gap between the rim of the hole is surely closed. To be done. Further, it is sufficient to pull the flange piece into the skirt recess and hold it at the pulled-in position, so that the work is sufficiently simplified.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, in the first embodiment of the pipe plug structure according to the present invention, the plug 10 comprises a plug body 12, a screw 14, and a nut 16. It is formed so that it can be inserted into the hole 20 on the side surface of the pipe material 18 by assembling a screw and a nut on the plug body.

In the present invention, as the pipe material 18,
FIG. 3 exemplifies a permanent anchor 22 smuth-sheath, and rust-proof oil injection holes filled in the smooth-sheath are
The hole 20 is used here. The injection hole (hole) 20 of the smooth-sheath (pipe material) is usually formed to have a diameter of about 10 mm.

In the permanent anchor 22, it becomes a tension material.
The PC steel strand 24 is fixed on the ground or the like by injecting and solidifying the grout (injection material) 26. In such a so-called anchor fixing length part, the PC steel strand 24 is
It is covered with a corrugated tube 28 called a tooth. And in the free length part with respect to the fixed length part of the permanent anchor 22,
The PC steel stranded wire 24 is a straight pipe-shaped smooth sheet.
It is covered by a spout 18 and is isolated from the grout 26.

Corrugated sheath side smooth-smooth
The ends of 18 are stopped by the water stop material 30, for example.
Then, a rust preventive oil 32 such as grease is filled around the PC steel wire 24 inside the smooth-sheath 18, and the smooth-smooth
The expansion and contraction of the PC steel wire with respect to the stainless steel wire is prevented, and the rust and corrosion of the PC steel wire in the smooth frame are prevented.

Injecting the rust preventive oil 32 into the smooth-sheath 18
It is carried out from the injection hole 20 by a pump means (not shown) such as a gear pump, and continues until an overflow occurs from the other end of the smooth space. After the rust preventive oil 32 has been injected, the plug 10 closes the injection hole 20 to prevent the rust preventive oil from flowing out, the drilling water, the ground water, etc. from flowing out from the injection hole.

As can be seen from FIGS. 1 and 2, for example, the flange 12a at the upper end and the skirt 12b at the lower end are integrally formed. The stopper body 12 is made of an elastic material, for example,
Molded from nitrile oil resistant rubber.

The skirt 12b of the stopper body is a smooth
The plug body 12 is formed to have a diameter that allows loose insertion into the injection hole 20 of the space, and by inserting the skirt into the insertion hole and engaging the large diameter flange 12a with the peripheral surface of the injection hole, the plug body 12 is smoothed. -Susage
It is inserted in 18 and locked. A ring-shaped seal may be sandwiched between the flange 12a and the smooth-sheath 18.

Further, as shown in FIG. 1, the skirt 12b is
Is formed with a recess 34 having an opening at the lower end. The recess 34 is formed in an inverted taper shape, for example. As can be seen from FIG. 2 in addition to FIG. 1, the recess 36 of the flange 12a and the recess 34 of the skirt are communicated by a through hole 38, and the screw 14 is inserted into the through hole from the flange side. It is freely rotatable and immovably embedded,
For example, a nut 16 as a flange piece having a diameter larger than the minimum diameter of the recess is screwed onto a screw on the opening side of the skirt recess to form the plug 10.

The flange recess 36 is typically the head of the screw 14.
It is formed to a depth and diameter that can accommodate 14a. The screw 14 is pre-embedded in the step of forming the plug body 12, for example.

The nut 16 is formed on the surface in the traveling direction, that is, the upper surface, for example, with a taper surface, and the diameter of the upper surface is smaller than the diameter of the lower end of the recess 34.

Here, the nut 16 is formed and arranged with at least partial fitting into the recess 34 of the skirt, and the friction force with the peripheral surface of the recess which acts by restoring from the elastic deformation of the skirt. Under this condition, rotation with respect to the skirt is prevented. In other words, with respect to the freely rotatable screw 14, the nut 16
Is prevented from rotating with respect to the skirt 12b, so that it is screwed, for example, in the axial direction of the screw under the rotation of the screw.

The screw 14 and the nut 16 are made of rust-proof metal such as stainless steel or brass. With such a configuration, it is possible to reliably prevent the screw 14 and the nut 16 from being rusted or corroded due to contact with groundwater or the like.

The plug 10 thus assembled is inserted into the injection hole 20 of the smooth space as shown in FIG.
In the initial state of the stopper 10, the nut 16 stands by at the lower position.

Then, from such a state, when the screw 14 is rotated in the corresponding direction, the nut 16 is screwed,
It is pulled upward, that is, toward the flange. Then
The diameter of the skirt expands due to the elastic deformation caused by the withdrawal of the nut 16. Since the recess 34 of the skirt is formed in the shape of an inverted taper, the expansion amount thereof increases as the nut 16 moves above the recess.

That is, as shown in FIG.
If the diameter of the skirt 12b is increased while the nut 16 is being pulled in until it comes into close contact with the peripheral edge of the injection hole 20, the injection hole can be closed. Then, as shown, the skirt 12
Since b is elastically deformed so as to be lifted from below, the peripheral surface of the injection hole is sandwiched between the flange 12a and the elastically deformed skirt in addition to the expansion of the diameter. for that reason,
From this point as well, the injection hole 20 is reliably closed by the plug 10.

Further, as shown in FIG. 5, even in the bending direction of the smooth-sheath 18 in which the flange 12a is difficult to adhere,
Expansion of the diameter of the skirt 12b and elastically deformed skirt
The injection hole 20 is reliably closed by sandwiching the injection hole peripheral surface by the flange and the flange.

As described above, in the hole closing method of the pipe material of the present invention, the diameter of the skirt 12b of the plug body is increased due to the elastic deformation of the skirt 12b when the nut 16 which is the flange piece is retracted. The injection hole 20 is closed. That is,
Due to the elasticity, the peripheral surface of the skirt 12b is brought into close contact with the peripheral edge of the injection hole 20, and the peripheral edge of the injection hole is tightly clamped by the flange 12a and the skirt, so that the injection hole is blocked. The certainty of is sufficiently improved.

Then, after the rust preventive oil 32 is injected, the smooth-
It suffices to insert the plug 10 into the injection hole 20 of the screw and rotate the screw 14 to the desired expansion amount of the skirt 12b. That is, screw 14
Since it functions as a means for retracting the nut 16 and a locking means for holding the nut 16 in the retracted position, the work of inserting and fixing the plug does not become complicated.

Further, at the same time when the injection hole 20 is closed by the expansion of the diameter of the skirt 12b, the plug body 12, that is, the plug 10 is clamped by the flange 12a and the skirt on the peripheral surface of the injection hole.
Since it is fixed to the smooth frame 18, there is no need to perform a separate fixing process such as taping. Therefore,
Also in this respect, the work can be simplified, and the workability when the injection hole is closed can be surely improved.

Further, since the skirt 12b is expanded under elastic deformation, neither the diameter of the skirt nor the diameter of the injection hole 20 is required to have high accuracy. That is, the plug body 12 can be easily formed and the injection hole 20 can be easily formed, and the work can be simplified in this respect as well.

Further, according to the plug structure for a pipe material of the present invention, the hole closing method can be appropriately performed, and the injection hole 20 can be surely closed easily despite the simple structure.

Here, in the embodiment, the rotation of the nut with respect to the skirt 12b is prevented by the frictional force generated when the nut 16 is fitted into the recess 34 of the skirt. However, it is not limited to the dependence only on the frictional force, and for example, as shown in FIG. 6, by the engagement protrusion 40 of the nut 16 and the engagement groove 42 of the slidable recess 34 of the engagement protrusion, -The rotation of the nut with respect to the throat 126 may be prevented.

In such a structure, the engaging protrusion 40 and the engaging groove are
Under the engagement with 42, the rotation of the nut 16 with respect to the skirt 12b is reliably prevented, so that the smooth screwing of the nut due to the rotation of the screw 14 can be easily ensured.

In FIG. 6, the engaging projection 40 is provided on the nut 16 and the engaging groove is provided on the peripheral surface of the recess 34. However, conversely, the engaging projection is provided on the recess. Engagement grooves may be provided in the nut on the peripheral surface. Also,
It goes without saying that the number of the engaging projections 40 and the engaging grooves 42 is not limited to a single number as shown in the drawing, and may be plural.

Further, in the embodiment, the nut 14 is drawn as a flange piece into the recess 12b of the skirt. However, the present invention is not limited to this. For example, as in the plug 110 according to the second embodiment of the present invention shown in FIG. 7, the head 114a of the screw 114 is provided as a flange piece in the recess 34 of the skirt. The screw head may be pulled into the recess of the skirt when the nut 116 is screwed and rotated on the flange side.

In such a structure, the head 114a of the screw 114 is rotated by the screw 114 as the nut 114 rotates as the nut 116 rotates.
Since the diameter of the skirt 112b is expanded due to the elastic deformation caused by being drawn into the concave portion 34 of the shoe, the smooth hole injection hole 20 can be surely closed in the same manner as described above.

The recess 34 of the skirt is illustrated as an inverted taper shape, but the invention is not limited to this, and for example, the stopper of the third embodiment of the present invention shown in FIG. 8 (A). The skirts 234 may be formed in a straight shape such as 210. In this case, in order to facilitate the screwing of the nut 216 with respect to the screw 214, for example, the surface in the traveling direction of the nut, that is, the upper surface is formed as a taper surface.

Even in such a straight recess 234, when the nut 116 is pulled into the recess by the rotation of the screw 214, the skirt 212b is elastically deformed as shown in FIG. 8 (B). It deforms under the influence of the skirt and the diameter of the skirt is smooth.
While expanding until it comes into close contact with the periphery of the injection hole 20
The peripheral surface of the injection hole is held by the skirt and the flange 212a. Therefore, even in such a structure, the injection hole 20 of the smooth-sheath can be easily and surely closed, and the same effect as that of the above embodiment can be sufficiently ensured.

Since it is sufficient to increase the diameter of the skirt under elastic deformation, the flange piece drawn into the recess of the skirt is not limited to the head of the nut or screw. That is,
As in the fourth embodiment of the present invention shown in FIG. 9 (A), the substantially disk-shaped flange piece 46 is integrally fixed to the support rod 44, and the flange piece is moved under the traction of the support rod. It may be configured to be drawn into the recess of the grate.

In such a structure, the support rod 46
Is formed, for example, by having either an engaging projection or an engaging groove on the peripheral surface. In the embodiment, the support rod 46 is formed with a thread groove-shaped engagement groove.

In the plug 310 having such a structure, the support rod 44 integrally having the flange piece 46 is rotatably and non-separably provided from the skirt side to the plug body 312, and the support rod 44 from the flange side is provided. By towing
As shown in FIG. 9 (B), the flange piece is a recess 33 of the skirt.
Be drawn into 4. Then, the flange piece 46 pulled in under the pulling of the support rod 44 is held in the retracted position by fixing the support rod by the locking means 48.

As the locking means 48, for example, a speed nut locked to the support rod 44 under fitting can be used.

Even in such a structure, the diameter of the skirts 312b is enlarged by pulling the flange pieces 46 into the recesses, so that the smooth hole injection hole 20 similar to that described above is used.
Can be reliably blocked.

Although the flange piece 46 integrally fixed to the support rod 44 is illustrated in the embodiment, a screw is used in place of the support rod and the flange piece, and a screw head is provided with a scalpel. After being pulled into the recess 334 of the shaft, the locking means 48 such as a speed nut may be used for locking and holding.

Further, in the embodiment, a thread groove-like engagement groove is provided on the peripheral surface of the support rod 44. However,
It suffices that the locking means 48 such as a nut nut can be locked with respect to the support rod 44 without slipping, and therefore a large number of engaging grooves other than the screw grooves may be provided. Further, the engaging means is not limited to the engaging groove, and an engaging protrusion may be provided on the peripheral surface of the support rod 44 so that the locking means can be held under the engagement with the engaging protrusion.

Since it is sufficient to hold the flange piece 46 at the retracted position, the locking means 48 is not limited to a speed nut, and other means such as E ring, C ring and adhesive can be used. You may use as.

In this embodiment, the smooth material forming the free length of the permanent anchor 22 is used as the pipe material 18, and the rust preventive oil is injected into the smooth material. The injection hole is embodied as hole 20. However, as long as it is a hole made in the pipe material, it can be smooth.
The plug structure for a pipe material of the present invention can be applied for the purpose of closing the holes of various pipe materials without being limited to the injection hole of the pipe material.

The material of the plug body, screw and nut is not limited to those described in the above embodiment.
However, if the stopper body is molded from an oil-resistant rubber material and the screws, nuts, etc. are formed from rust-preventing metal such as stainless steel or brass, its deterioration can be reliably suppressed even in contact with rust-preventing oil. In particular, it can be effectively utilized in the injection hole 20 of the smooth-seam of the permanent anchor 22 which comes into direct contact with the rust preventive oil.

Further, in the embodiment, the upper surface of the nut is formed as a taper surface, but it is sufficient if smooth nut advancement is ensured and the peripheral surface of the recess is prevented. The shape is not limited to this, and may be, for example, a normal chamfered shape.

Since the screw exemplified in the embodiment is sufficient if it has a shape having an integral head, a general bolt is also included in the screw here.

The above-mentioned embodiments are for explaining the present invention and do not limit the present invention in any way.
It goes without saying that the present invention includes all those which are modified or modified within the technical scope of the present invention.

[0054]

As described above, in the hole closing method for pipe material according to the present invention, the plug is inserted into the hole of the pipe material,
Since the diameter of the skirt is enlarged and the hole is closed by pulling in the flange piece, the peripheral surface of the skirt is closely adhered to the peripheral edge of the hole, and the flange and the skirt are clamped.
The hole is securely closed.

Then, it is sufficient to insert the plug into the hole, pull the flange piece up to the desired expansion amount of the skirt, and hold the flange piece at the retracted position, so the work of inserting and fixing the plug becomes complicated. do not do.

Further, at the same time when the hole is closed due to the increase in the diameter of the skirt, the plug body, that is, the plug is fixed to the pipe material by sandwiching the hole peripheral surface between the flange and the skirt. Therefore, it is not necessary to perform a fixing work in another process by taping or the like. Therefore, also in this respect, the work can be simplified and the workability at the time of closing the hole is surely improved.

Further, since the skirt is expanded under elastic deformation, neither the diameter of the skirt nor the diameter of the hole requires high precision. That is, the plug body can be easily formed and the holes can be easily formed, and the work can be simplified in this respect as well.

Further, according to the plug structure for a pipe material of the present invention, the hole closing method can be appropriately performed, and the hole can be surely closed easily despite the simple structure.

Further, whether the nut or the head of the screw is used as the flange piece, the skirt diameter of the plug body can be easily expanded by pulling it into the recess, and the screw or nut can be easily rotated. Under the accompanying retraction, it is possible to easily secure the retraction and holding of the nut and the screw head, which will be the flange piece, so that simplification of the configuration and complication of work can be reliably prevented.

If the surface of the nut in the traveling direction is the taper surface, the smooth threading of the nut due to the rotation of the screw can be sufficiently obtained, and the inner surface of the skirt of the skirt can be sufficiently damaged. Can be suppressed.

Furthermore, if the stopper body is molded from an oil resistant rubber material and the screws, nuts, etc., are formed from a rust preventive metal such as stainless steel, brass, etc., the deterioration can be surely made even in contact with the rust preventive oil. Since it can be suppressed, it can be particularly effectively used as a plug structure of the injection hole of the permanent anchor, which is in direct contact with the rust preventive oil.

Further, the present invention is not limited to the combination of screws and nuts, and the structure in which the flange piece integral with the support rod can be pulled into the recess of the skirt and held by the locking means at the pulling position is the same as the above. A plug structure capable of ensuring the same effect can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a plug structure for pipe material according to a first embodiment of the present invention before closing.

FIG. 2 is a schematic exploded perspective view of a stopper in the pipe material stopper structure of the first embodiment.

FIG. 3 is a schematic vertical sectional view of a permanent anchor.

FIG. 4 is a schematic vertical cross-sectional view of the plug structure for pipe material according to the first embodiment after being closed.

FIG. 5 is a schematic vertical cross-sectional view of the plug structure for pipe material after closing according to the first embodiment, in a direction orthogonal to the axis of the smooth-sheath.

FIG. 6 is a schematic exploded perspective view of a plug in a modified example of the pipe material plug structure of the first embodiment.

FIG. 7 is a schematic vertical cross-sectional view of the plug structure for pipe material according to the second embodiment of the present invention before closing.

FIG. 8 is a third view of the present invention before and after occlusion.
It is each schematic longitudinal cross-sectional view of the plug structure for pipe materials which concerns on an Example.

FIG. 9 is a fourth view of the present invention before and after occlusion.
It is each schematic longitudinal cross-sectional view of the plug structure for pipe materials which concerns on an Example.

[Explanation of symbols]

 10, 110, 210, 310 stopper 12, 112, 212, 312 stopper body 12a, 112a, 212a, 312a flange 12b, 112b, 212b, 312b skirt 14, 114, 214, 314 screw 114a screw head (flange Pieces) 16,216 Nuts (flange pieces) 116,316 Nuts 18 Pipe material (Smooth-sheath) 20 Holes (injection hole) 22 Permanent anchors 34, 234, 334 Scratch recess 40 Engagement projection 42 Engagement Groove 44 Support rod 46 Flange piece 48 Locking means

Claims (9)

[Claims] 1. A skirt of a plug body extending below a flange is inserted into a hole of a pipe material, and a flange piece having a diameter larger than the minimum diameter of the recess of the skirt is inserted into the recess of the skirt. The skirt that is generated by pulling in the flange piece.
A method for closing a hole in a pipe material by closing the hole in the pipe material by elastically expanding the diameter of the pipe. 2. A pipe material plug structure for closing a hole formed in a side surface of a pipe material, wherein a flange at an upper end portion and a skirt at a lower end portion having a recess opened at a lower end are integrally formed. A stopper main body formed of an elastic material capable of elastically deforming the skirt; provided rotatably and non-separably with respect to the main body via a flange of the stopper main body and a through hole penetrating the skirt. A nut having an outer diameter larger than the diameter of the recess of the skirt and capable of being screwed in the skirt as the screw rotates while preventing rotation of the skirt. For pipe material, characterized in that the diameter of the skirt can be elastically expanded by pulling the nut into the recess of the skirt when the screw is rotated. Stopper structure. 3. A pipe material plug structure for closing a hole formed in a side surface of a pipe material, wherein a flange at an upper end portion and a skirt at a lower end portion having an inverted taper-shaped recess are elastically deformed. A plug body integrally molded from a possible elastic material; a screw provided rotatably and non-separably with respect to the body via a flange of the plug body and a through hole penetrating the skirt; And a nut that is formed to have a diameter larger than the minimum diameter of the recess of the skirt and that can be screwed in the skirt with rotation of the screw while preventing rotation with respect to the skirt. A plug structure for pipe material, characterized in that the diameter of the skirt can be elastically expanded under the pulling of the nut into the skirt recess along with the rotation of the screw. 4. The plug structure for a pipe material according to claim 2, wherein the surface of the nut in the traveling direction is formed as a taper surface. 5. A pipe material plug structure for closing a hole formed in a side surface of a pipe material, wherein a flange at an upper end portion and a skirt at a lower end portion having a recessed portion at an lower end portion can be elastically deformed. Body integrally formed from a flexible elastic material; a screw rotatably and irremovably attached to the body via a flange of the body, a through hole penetrating the skirt, and a bottom diameter of the skirt. Nut having a reverse taper shape larger than the diameter of the recess of the skirt and capable of screwing in the skirt with rotation of the screw while preventing rotation with respect to the skirt. The plug structure for pipe material is characterized in that the diameter of the skirt can be elastically expanded under the pulling of the nut into the recess of the skirt when the screw is rotated. 6. A nut is fitted into the recess of the skirt, and a friction force is generated by the close contact of the nut outer peripheral surface with the peripheral surface of the recess of the skirt when the skirt is restored. 6. The plug structure for a pipe material according to claim 2, wherein rotation of the nut with respect to the skirt can be prevented. 7. The plug structure for a pipe material according to claim 2, wherein the plug body is formed of a nitrile-based oil resistant rubber material, and the screws and nuts are formed of a rust preventive metal. 8. A plug structure for a pipe material for closing a hole formed in a side surface of a pipe material, wherein a flange at an upper end portion and a skirt at a lower end portion having a recessed opening at a lower end are integrally formed. And a stopper body formed of an elastic material to enable elastic deformation of the skirt;
Is formed with a head having a diameter larger than the minimum diameter of the concave portion of the plug, and can be freely rotated with respect to the main body by insertion from the skirt side through a through hole that penetrates the flange and the skirt of the plug main body. A plug is provided with a non-detachable screw; a nut screwed to the screw on the flange side of the plug body, and the head of the screw into the skirt recess as the nut rotates. The plug structure for pipe material is characterized in that the skirt diameter can be elastically expanded under the pulling in of. 9. In a pipe material plug structure for closing a hole formed in a side surface of a pipe material, a flange at an upper end portion and a skirt at a lower end portion having a recessed opening at a lower end are integrally formed. And a plug main body formed of an elastic material to enable elastic deformation of the skirt; a large number of engaging projections or engaging grooves are provided on the peripheral surface, and more than the minimum diameter of the recess of the skirt. A plug having a large-diameter flange piece integrally, and a support rod movably provided in the axial direction with respect to the main body via a flange of the main body of the plug and a through hole penetrating the skirt. Is formed, the skirt diameter can be elastically expanded under the pulling of the flange piece into the skirt recess along with the pulling of the support rod, and the skirt peripheral surface to the hole peripheral edge can be formed. When the support rod is locked by the locking means after the Plug structural pipe member, characterized in that the can hold.