JP2010270880A - Pipe connecting method and pipe connecting structure for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe connecting method and a pipe connecting structure, allowing connection with high sealing performance without using any intervening member such as a seal material although being simple in structure and improved to be simply executable in the field. <P>SOLUTION: Between connection openings 3, 4 of tubular members 1, 2 to be butt-connected, the connection opening 3 is formed in a socket 5a having a butt connection part 5 which is formed in an almost L shape as viewed in the cross section. The connection opening 4 is formed in a spigot 6a having a butt connection part 6 which is formed in an almost L shape as viewed in the cross section. The spigot 6a is butted against and set inside the socket 5a and is fastened from an outer peripheral side of the socket 5a by a fastening member 7, so that seal bearing pressure is increased in both two surfaces in a pipe longitudinal direction and a pipe circumference direction of the tubular members 1, 2 and the connection openings 3, 4 are connected with each other. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a pipe connecting method and a pipe connecting structure for tubular members such as straight pipes, elbow pipes and other deformed pipes formed of metal or other hard materials, and in particular, connection between tubular members to be butt-connected. The present invention relates to a pipe connection method and a pipe connection structure for a ventilator such as a range hood, which are effective for bringing the mouths into pressure contact and connecting with high sealing performance.

The tubular member connected by abutting the connection ports is provided with a flange projecting in the outer peripheral direction from the opening edge, and this flange is abutted with each other and connected using a tightening member such as a bolt or a nut. This is a commonly used connection technique.
By the way, the method of simply butting the flanges provided at the connection ports of the tubular member formed of metal or other hard material cannot be expected to have high sealing performance between the flanges.

  Therefore, in order to improve the sealing performance between the flanges, a belt is provided along the outer peripheral surface of the flanges so that the flanges are pressed against each other along the outer peripheral surface of the flanges. A pipe connection structure developed to enhance the sealing performance between flanges by tightening in the direction of diameter reduction by a member has been proposed and known (for example, see Patent Document 1).

Japanese Patent No. 2941687 (see paragraph No. 0010 and FIGS. 1 and 2)

  However, in the prior art described in Patent Document 1, in order to tighten the flanges in the direction in which they are pressed against each other by the belt (in the direction of the arrow in FIG. 2), the inner sloped surface is interposed between the flange and the inner sloped surface of the belt. It is necessary to interpose spacer ring materials having outer sloped surfaces that come into pressure contact with each other so that there is a problem in handling such as troublesome and troublesome connection setup at the site.

Further, there is a limit to enhancing the sealing performance only by pressure contact between flanges made of metal or other hard material, that is, pressure contact in the tube tube direction (butting direction). That is, in order to improve the sealing performance by press-contacting surfaces, it is possible to secure a wide press-contact surface, but a gas or liquid is circulated by connecting tubular members such as straight pipes, elbow pipes and other deformed pipes. In a pipe connection structure that is applied to install a pipe line, in order to enable pipe piping in a narrow space, the outer peripheral protrusion width (flange outer diameter) of the flange from the opening edge is There are some limitations.
Therefore, in the prior art, as shown in FIG. 2, a sealing material (packing material) made of elastic rubber or the like is provided between the flanges in order to improve the sealing performance with a limited outer peripheral protrusion width of the flange. There are many assembly parts in the field including the spacer ring material, such as the necessity of interposition, and the workability is very poor, such as requiring a lot of time for connection setup.

  Therefore, the present invention was created to solve the above-described problems, and can be connected with high sealing performance without using any intervening member such as a sealing material while having a simple structure. In addition, it is an object of the present invention to provide a new pipe connection method and its pipe connection structure which are improved so as to be easily constructed on site.

In order to solve the above-mentioned problem, in the present invention, a pipe connection method for connecting by connecting the connection ports of tubular members that are butt-connected to each other,
The connection port of the tubular member is provided with a butt connection portion having a pressure contact surface that is pressed against the tube direction and the tube circumferential direction, respectively, and the butt connection portions are brought into butt contact with each other, and the outer peripheral surface thereof. It is characterized by being pressed from both the tube tube direction and the tube circumferential direction by tightening with a tightening member from the side.

  According to the pipe connection method having such a configuration, after connecting the connection ports of the tubular members to each other, the butt connection portion provided in the connection port is tightened from the outer peripheral surface side by the tightening member, so that the butt connection The portions are pressed against each other in pressure contact surfaces (both in the tube tube direction and the tube circumferential direction) in the tube tube direction (tube butt direction) and the tube circumferential direction (tube diameter direction). That is, high sealing performance is ensured between the connection ports of the tubular member by the pressure contact force (seal surface pressure) in the tube tube direction and the pressure contact force (seal surface pressure) in the tube circumferential direction, which are increased by the tightening member.

Moreover, in the present invention, a pipe connection structure for connecting the butt connection portions provided at the connection ports of the tubular members that are butt-connected to each other by butt pressure contact,
Among the connection ports, the butt connection portion provided at one connection port includes a first seat surface portion that protrudes from the opening edge in the outer peripheral direction, and the other connection port from the outer peripheral edge of the first seat surface portion. A receiving port formed in a substantially L shape in a cross-sectional view from the second seating surface portion projected in the direction of the tube of the direction,
The butt connection portion provided in the other connection port includes a first contact surface portion that protrudes in an outer peripheral direction from an opening edge portion and butt-contacts with the first seat surface portion, and the first contact surface portion. In a cross-sectional view, the second contact surface portion protrudes from the outer peripheral edge of the contact surface portion in the same tube direction as the second seat surface portion and is slidably contacted to the inner side of the second seat surface portion. An insertion opening formed in a substantially L shape,
The insertion opening is made to butt inside the receiving opening, and is tightened by a fastening member from the outer peripheral surface side of the second seating face portion of the receiving opening, so that the first seating surface portion, the first contact surface portion, and the second contact surface portion The seat surface portion and the second contact surface portion are formed so as to be in pressure contact with each other.

  Here, in a state where the insertion port is butt-incorporated into the receiving port, the open end portion of the second contact surface portion is formed so as to protrude in the tube direction from the open end portion of the second seat surface portion. Further, the tightening member is equipped with a band wound around the outer peripheral surface of the second seating surface portion of the receiving port, and a circumferential open end of the band, and the band is reduced in diameter. The band portion is wound along the outer peripheral surface of the second seating surface portion with a width dimension of the second seating surface portion of the receiving port or less than the width dimension of the second seating surface portion. 1 is formed from a first pressing portion and a second pressing portion that is connected in a substantially C shape in cross-sectional view from both ends in the width direction of the first pressing portion and has an inner side as a tapered pressing surface. Be suitable

According to the pipe connection structure having such a configuration, the insertion port side is coaxially opposed to the receiving port side of the tubular members that are butt-connected to each other, and the butt is present inside the butt. The seating surface portion is tightened from the outer peripheral surface side by a tightening member.
At this time, the open end portion of the second contact surface portion on the insertion port side protruding from the open end portion of the second seat surface portion on the receiving port side in the tube direction, the first seat surface portion on the receiving port side and the second The taper pressing surface of the second pressing part of the band of the tightening member can be slidably contacted with the corner part continuously provided with the seating surface part of the tightening member, and the taper pressing is performed as the band is tightened in the diameter reducing direction by the tightening tool. The insertion port is pressed toward the receiving side by the surface, the first contact surface portion on the insertion port side is pressed against the first seat surface portion on the receiving port side, and at the final stage of tightening the band by the fastener, The second seating surface portion on the receiving port side is pressed against the second contact surface portion on the insertion port side by the first pressing portion, and the second seating surface portion on the receiving port side is pressed against the second pressing portion on the insertion port side. Press contact.
Further, the taper angle of the second seating surface portion on the receiving port side and the second abutting surface portion on the insertion port side, and the first pressing portion from the open end of the second pressing portion of the band to this size. Depending on the size of the band, such as the height (depth) of the band to be reached and the taper angle of the taper pressing surface of the second pressing part, the insertion port may be inserted at the final stage when the band is tightened by the fastener. The second contact surface portion on the side is pressed against the second seat surface portion on the receiving port side.
Thereby, between the 1st seat surface part and 1st contact surface part of the pipe tube direction (tube butt | matching direction) of a receptacle and an insertion port, and the 2nd seat surface part of a pipe circumferential direction (tube diameter direction) The pressure contact force (seal surface pressure) between the first contact surface portion and the second contact surface portion is increased by tightening the band by the fastener, and the connection ports of the tubular members are connected with high sealing performance.

  Further, in the pipe connection structure, the inner side surface of the second seat surface portion and the outer side surface of the second contact surface portion that are press-contacted in the pipe circumferential direction by tightening by the tightening member are formed in a tapered shape. Has been. That is, when the insertion port is caused to butt against the receiving port, the inner side surface of the second seating surface portion and the outer side surface of the second abutting surface portion are sequentially brought into contact with the butt operation. It is preferable that the taper is formed.

  According to the pipe connection structure configured in this way, as described above, when the insertion port is made to butt against the receiving port, the butt operation can be easily performed. In other words, at the initial stage where the insertion port is made to butt in the receiving port, the diameter on the receiving port side is large and the diameter on the insertion port side is small. Thus, the insertion opening can be easily brought into the butting opening.

According to the pipe connection method of the present invention, the connection ports of the tubular members that are butt-connected to each other include a butt connection portion provided in the connection port, and a tubular member by a tightening member that tightens the butt connection portion from the outer peripheral surface side. It is press-contacted in each pressure-contact surface of a direction (pipe butt direction) and a pipe circumferential direction (pipe diameter direction).
Thereby, the connection port of a tubular member can be connected with high sealing performance by simple construction, without using interposition members, such as a sealing material, like the prior art.

According to the pipe connection structure of the present invention, between the pressure contact surfaces of the first seat surface portion and the first contact surface portion in the tube direction of the receiving port and the insertion port by tightening the band in the diameter reducing direction by the fastener. Further, the pressure contact force (seal surface pressure) between the pressure contact surfaces of the second seat surface portion and the second contact surface portion in the pipe circumferential direction is increased to connect the connection ports of the tubular members with high sealing performance. can do.
In addition, when the insertion port side is made to butt inside the receiving port, at the initial stage of the butt, the diameter on the receiving port side is large and the diameter on the insertion port side is small, so that the insertion port can be easily butt-incorporated in the receiving port. Can do.
As described above, according to the present invention, the connection ports of the tubular members are connected to each other in the tube direction and the tube circumferential direction without using any intervening member such as a sealing material as in the prior art. It is possible to connect with high sealing performance by the surface pressure contact force (seal surface pressure). Moreover, it is possible to provide a pipe connection structure that has a simple structure and can be easily constructed.

It is a side view which fractures | ruptures and abbreviate | omits and shows a part of connection form of the tubular member to which the pipe connection structure which concerns on this embodiment was applied. It is the II-II longitudinal cross-sectional view of FIG. Part of the tubular member provided with the receiving port side is omitted and shown, (a) is a perspective view, and (b) is a longitudinal side view of the same. A part of the tubular member provided with the insertion port side is omitted and shown, (a) is a perspective view, and (b) is a longitudinal side view of the same. It is a perspective view which shows a clamping member. A state when the receiving port and the insertion port are brought into butt contact with each other and connected by a tightening member is shown, (a) is an enlarged cross-sectional view of the main part showing a state where the insertion port faces the receiving port, b) is an enlarged cross-sectional view of the main part showing a state in which the insertion opening is brought into abutment with the receiving opening and the band is wound and set along the outside of the second seating surface portion on the receiving opening side. An example of piping use of the tubular member to which the pipe connection structure concerning this embodiment is applied is shown, (a) is a perspective view when a ventilator is seen from the front side slanting upper part, and (b) is the front. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
The pipe connection method and the pipe connection structure according to the present embodiment are pipes that circulate gas or liquid using a tubular member such as a straight pipe, elbow pipe, or other deformed pipe formed of metal or other hard material. It is effective in the field such as pipe connection with high sealing performance, and its use is not particularly limited. That is, as shown in FIG. 1, it is intended to connect tubular members 1 and 2 having connection ports 3 and 4 that are butt-connected to each other.

FIG. 1 is a side view showing a tubular member connecting form to which a pipe connecting structure for carrying out a pipe connecting method according to the present embodiment is applied, with a part thereof broken and omitted, and FIG. 2 is a longitudinal sectional view of the same. It is.
That is, as shown in FIGS. 1 and 2, the pipe connection structure according to the present embodiment includes butt connection portions 5 and 6 in the connection ports 3 and 4 of the tubular members 1 and 2 that are butt-connected to each other, The butt connection portions 5 and 6 are brought into butt contact with each other and tightened by the fastening member 7 from the outer peripheral surface side, so that the tubular direction of the tubular members 1 and 2 (tube butt direction) and the pipe circumferential direction (tube diameter direction). And the pressure contact surfaces (both two surfaces in the tube tube direction and the tube circumferential direction) to connect the connection ports 3 and 4 with high sealing properties.

≪Configuration of tubular member≫
FIG. 3 is a perspective view and a longitudinal sectional view showing a tubular member having a receiving port side, and FIG. 4 is a perspective view and a vertical side view showing the tubular member having an insertion port side. Here, description will be made with reference to FIG. 1 as appropriate.
The tubular members 1 and 2 are formed of a nonflammable material. For example, it is formed using a steel plate made of stainless steel or zinc having a thickness of 0.6 mm or more.
For example, as shown in FIG. 7 which will be described later, the tubular members 1 and 2 are connected to a connection exhaust port 41 or a ceiling behind a ventilation device 40 such as a range hood that sucks and captures contaminated air generated during cooking. It is fitted and connected to a joint duct 51 of an exhaust duct 50 that is piped and exhausts contaminated air to the outside or an external exhaust port (not shown) that exhausts contaminated air to the outside by being installed on a kitchen wall (building wall) or the like. It is formed in a cylindrical shape with a certain diameter.
And the butt connection parts 5 and 6 are each provided in the connection ports 3 and 4 by which the tubular members 1 and 2 formed in this way are butt-connected.

≪Configuration of butt connection part≫
The butt connection portions 5 and 6 include a receiving port 5a side shown in FIGS. 3 (a) and 3 (b) and an insertion port 6a side shown in FIGS. 4 (a) and 4 (b).
The receiving port 5a has a first seat surface portion 5a-1 projecting from the opening edge of the opening portion 3 in the outer peripheral direction, and the other peripheral edge of the first seat surface portion 5a-1 as shown in FIG. It is formed in a substantially L shape in a sectional view from the second seating surface portion 5a-2 projecting in the tube direction of the connection port 4.
And the 2nd bearing surface part 5a-2 of the receiving port 5a formed in this way is taper-shaped at a suitable inclination angle toward the outer side, as shown to (a) and (b) of FIG. Widened and formed.

The insertion opening 6a protrudes from the opening edge of the opening 4 in the outer circumferential direction, and the first contact surface portion 6a-1 that abuts against the first seat surface portion 5a-1 and the first contact surface portion 6a-1. A second contact which protrudes from the outer peripheral edge of the surface portion 6a-1 in the same tube direction as the second seat surface portion 5a-2 and is slidably contacted to the inside of the second seat surface portion 5a-2. It is formed in a substantially L shape in cross-sectional view from the contact surface portion 6a-2.
And the 2nd contact surface part 6a-2 of the insertion port 6a formed in this way is 2nd seat surface part 5a- by the side of the receiving port 5a, as shown to (a) and (b) of FIG. 2 is widened in a tapered shape at substantially the same inclination angle as 2.
Thereby, as shown in FIGS. 6A and 6B described later, when the insertion opening 6a faces the receiving opening 5a so as to be in contact (in contact), the matching operation can be easily performed. I am doing so.

≪Configuration of tightening member≫
FIG. 5 is a perspective view showing a tightening member. Here, description will be made with reference to FIGS. 1 and 2 as appropriate.
As shown in FIG. 5, the tightening member 7 includes a band 7 a and a tightening tool 7 b that pulls the side of the band 7 a close to the circumferential open end and tightens the band 7 a in the diameter reducing direction. Has been.

As shown in FIGS. 1 and 2, the band 7a is wound and set around the entire circumference of the second seat surface portion 5a-2 along the outside of the second seat surface portion 5a-2 on the receiving port 5a side. It is formed in length.
The band 7a includes a first pressing part 7a-1 having a width dimension equal to or smaller than the width of the second seating surface part 5a-2 on the receiving port 5a side, and the width of the first pressing part 7a-1. It is formed in a substantially trapezoidal shape in a sectional view from a second pressing portion 7a-2 that is provided in a substantially C shape (a divergent shape) in a sectional view from both ends in the direction and has an inner side as a tapered pressing surface 11. Thus, as shown in FIG. 6B described later, when the band 7a is fitted and set from the outer peripheral surface side of the second seat surface portion 5a-2 of the receiving port 5a in which the insertion port 6a is abutted, the set The work can be done promptly.
Further, when the set band 7a is tightened by the fastener 7b, as shown in the enlarged view of FIG. 1 and FIG. 6B, the tube end direction from the open end of the second seat surface portion 5a-2. The insertion port 5a is pressed to the receiving port 5a side by the taper pressing surface 11 that slidably contacts the open end 12 of the second contact surface portion 6a-2 on the insertion port 6a side protruding to the side. Thereby, the press contact force (seal surface pressure) between the 1st seat surface part 5a-1 of the receiving port 5a and the 1st seat surface part 6a-1 of the insertion port 6a is improved, and the receiving port 5a with much higher sealing performance. It can be applied between the insertion opening 6a.

  Then, on both ends open side of the band 7a, as shown in FIGS. 2 and 5, a substantially L-shaped connecting member 13 constituting the fastening tool 7b is provided by welding or other fixing means, respectively. A fastening bolt 14 is screwed and attached between the connecting members 13.

  The tightening bolt 14 is formed of a head portion 14 a and a screw portion 14 b extending between the connecting members 13. The peripheral surface of the head portion 14a is provided with anti-slip material such as knurls, and the end surface of the head portion 14a is provided with a hexagonal wrench locking recess (not shown) or a cross groove for a driver. Yes.

[Description of pipe connection method]
Next, a pipe connection method of the tubular member 1 using the pipe connection structure configured as described above will be described.
FIG. 6 is an enlarged cross-sectional view of the main part showing a state when the fastening member is set by abutting and contacting the receiving port and the insertion port. Here, description will be made with reference to FIGS. 1 and 2 as appropriate.
First, as shown to (a) and (b) of FIG. 6, the receiving port 5a and the insertion port 6a are made to face, and the insertion port 6a is made to abut against the receiving port 5a.
At this time, the second seating surface portion 5a-2 on the receiving port 5a side and the second abutting surface portion 6a-2 on the inserting port 6a side have a taper shape that is expanded outward, so that the inserting port is inserted into the receiving port 5a. At the initial stage of bringing 6a into butt (the inlet side of the receiving port 5a), as shown in FIG. 6 (a), the diameter on the receiving port 5a side is large, and the diameter on the insertion port 6a side is small. Thereby, the insertion opening 6a can be easily made to butt in the receiving opening 5a.

Next, as shown in FIG. 6B, the band 7a is wound from the outer surface side of the second seat surface portion 5a-2 of the receiving port 5a along the outer side of the second seat surface portion 5a-2. By turning the tightening bolt 14 and tightening the band 7a in the direction of diameter reduction, the receiving port 5a and the insertion port 6a can be connected as shown in FIGS.
At this time, as shown in FIG. 6B, the second contact surface portion on the insertion port 6a side that protrudes from the open end 15 of the second seat surface portion 5a-2 on the reception port 5a side in the tube direction. As shown in the enlarged view of FIG. 1, the open end 12 of 6a-2 and the continuous corner 16 of the first seating surface 5a-1 and the second seating surface 5a-2 on the receiving port 5a side. The taper pressing surface 11 of the second pressing portion 7a-2 of the band 7a is slidably movable, and as the band 7a is tightened in the direction of diameter reduction by the tightening bolt 14, the taper pressing surface 11 causes the insertion port 6a side. Is pressed to the receiving port 5a side, the first contact surface portion 6a-1 on the insertion port 6a side is pressed against the first seat surface portion 5a-1 on the receiving port 5a side, and the band 7a is tightened by the tightening bolt 14. In the final tightening stage, the first pressing portion 7 of the band 7a -1 causes the second seating surface portion 5a-2 on the receiving port 5a side to be pressed against the second contact surface portion 6a-2 on the insertion port 6a side, so that the second seating surface portion 5a-2 is second contacted. It is press-contacted to the surface part 6a-2.
At this time, the taper angle of the second seat surface portion 5a-2 on the receiving port 5a side and the second contact surface portion 6a-2 on the insertion port 6a side and the second pressing of the band 7a against this size The height (depth) of the band from the open end of the portion 7a-2 to the first pressing portion 7a-1, the size of the taper angle of the tapered pressing surface 11 of the second pressing portion 7a-2, etc. Depending on the size relationship of the band 7, when the band 7a is tightened in the direction of diameter reduction by the tightening bolt 14, the second contact surface portion 6a-2 on the insertion port 6a side becomes the second seat surface portion 5a on the receiving port 5a side. -2 will be in good pressure contact.
As a result, between the pressure contact surfaces of the first seat surface portion 5a-1 and the first contact surface portion 6a-1 in the tube tube direction, and between the second seat surface portion 5a-2 in the tube circumferential direction and the second contact surface portion. The pressure contact force (seal surface pressure) between the pressure contact surfaces with the contact surface portion 6a-2 is increased, and the receiving port 5a and the insertion port 6a are connected with high sealing performance.

FIG. 7 is a perspective view and a front view showing an example of pipe use of a tubular member to which the pipe connection structure according to this embodiment is applied. Here, description will be made with reference to FIG. 1 as appropriate.
In an example of the use of this pipe, as shown in FIGS. 1 and 7, one end side of a pipe having a receiving port 5a and an insertion port 6a connected in a pipe connection structure, a connection exhaust port 41 on the ventilation device 40 side, and Two tubular members made of deformed pipes that are misaligned with the other end of the pipe that is connected to the exhaust duct 50 that passes through the kitchen ceiling K from the back of the ceiling and faces the pipe in the kitchen (indoor) via the joint duct 51. The piping which connects the connection exhaust port 41 of the ventilation apparatus 40 and the exhaust duct 50 on the back of the ceiling will be described with reference to FIGS.

  First, as in the above-described embodiment, the receiving port 5a and the insertion port 6a of the tubular members 1 and 2 are brought into butt contact with each other, the band 7a is set, and the band 7a is tightened in the reduced diameter direction by the tightening bolt 14. The receiving port 5a side and the insertion port 6a side of the tubular members 1 and 2 are connected. At this time, the fastening state of the band 7a by the fastening bolt 14 is temporarily set so that the tubular members 1 and 2 can rotate in the pipe circumferential direction, and the other end side of the tubular member 1 is connected to the ventilator 40 side connection exhaust port. 41 to fit and connect.

Next, the tubular member 2 side rotatably connected to the tubular member 1 side is rotated so that the other end side axial core (eccentric tube shaft) of the annular member 2 is exhausted from the kitchen ceiling K to the kitchen. Centering adjustment is performed so as to be positioned coaxially with the opening axis of the duct 50. At this time, the annular member 1 side connected to the connection exhaust port 41 of the ventilation device 40 is rotated as necessary. Thereby, the direction adjustment operation | work with respect to the core shift | offset | difference of the connection direction of the connection exhaust port 41 of the ventilation apparatus 40 and the opening part of the exhaust duct 50 which faces the kitchen ceiling K can be performed smoothly.
In this way, after aligning the other end side axis of the annular member 2 and the opening axis of the exhaust duct 50, the joint duct 51 is connected to the other end side of the annular member 2 and the opening of the exhaust duct 50. The band 7a in the temporarily fixed state is finally tightened with the tightening bolts 14 while being fitted and connected.
Accordingly, as shown in FIG. 7, the connection exhaust port 41 and the exhaust gas are adjusted by the direction adjustment corresponding to the misalignment of the connection direction between the connection exhaust port 41 of the ventilation device 40 and the opening of the exhaust duct 50 facing the kitchen ceiling K. The duct 50 can be easily connected by piping.

The specific configuration of the embodiment of the present invention is not limited to the above-described embodiment, and there are design changes and the like without departing from the gist of the present invention described in claims 1 to 5. Are also included in the present invention.
For example, as a fastener 7b of the band 7a, a plurality of latching grooves are arranged in the longitudinal direction on one open end side of the band 7a, and on the other open end side of the band 7a in the tightening direction of the band 7a according to the lever principle. It can be comprised from the fastener which has the operation part closed and the clamp ring with which this operation part was equipped, and it was detachably hooked in either of the said latching grooves. Further, the fastening ring pivotally attached to the open one end side of the band 7a is detachably engaged with any one of a plurality of retaining grooves provided in a fastening metal fitting pivotally attached to the other open end side. The fastener can be closed (turned down) in the fastening direction of the band 7a.

  Further, with respect to one or both of the second seating surface portion 5a-2 on the receiving port 5a side and the second abutting surface portion 6a-2 on the insertion port 6a side, substantially V-shaped or the like at one to several circumferential directions. A slit (slit) can be provided. Thereby, when the band 7a is tightened in the diameter reducing direction by the tightening bolt 14, and is pressed by the first pressing portion 7a-1 of the band 7a, the tapered second seat surface portion 5a that expands in the same direction. -1 and the second contact surface portion 6a-2 are in good pressure contact.

DESCRIPTION OF SYMBOLS 1, 2 Tubular member 3, 4 Connection port 5,6 Butt connection part 5a Receiving port 5a-1 1st seat surface part 5a-2 2nd seat surface part 6a Insertion port 6a-1 1st contact surface part 6a-2 1st 2 abutting surface portion 7 tightening member 7a band 7b tightening tool 11 taper pressing surface 12, 15 open end portion 16 continuous corner portion

Claims (5)

A pipe connection method for connecting the connection ports of tubular members that are butt-connected to each other by pressure contact,
The connection port of the tubular member is provided with a butt connection portion having a pressure contact surface pressed from the tube direction and the tube circumferential direction, respectively, and the butt connection portions are brought into butt contact with each other. A pipe connection method characterized in that the pipe is pressed from both the tube cylinder direction and the pipe circumferential direction by tightening with a fastening member from the surface side. A pipe connection structure in which butt connection portions respectively provided at connection ports of tubular members to be butt connected to each other are brought into close contact with each other by butt pressure contact,
Among the connection ports, the butt connection portion provided in one connection port includes a first seat surface portion projecting from the opening edge portion in the outer peripheral direction, and the other connection port from the outer peripheral edge of the first seat surface portion. A second seating surface portion projecting in the direction of the tube, and a receiving port formed in a substantially L shape in cross-sectional view,
The butt connection portion provided in the other connection port includes a first contact surface portion that protrudes in an outer peripheral direction from an opening edge portion and is butt-contacted with the first seat surface portion, and the first contact surface portion. In a cross-sectional view, the second contact surface portion protrudes from the outer peripheral edge of the surface portion in the same tube direction as the second seat surface portion and is slidably contacted to the inner side of the second seat surface portion. An insertion opening formed in a substantially L shape,
The insertion opening is caused to butt inside the receiving opening, and is tightened by a fastening member from the outer peripheral surface side of the second seating face portion of the receiving opening, so that the first seating surface portion, the first contact surface portion, and the second contact surface portion A pipe connection structure, wherein the seat surface portion and the second abutting surface portion are formed in pressure contact with each other.   The open end of the second contact surface portion is formed so as to protrude in the tube direction from the open end portion of the second seat surface portion in a state where the insertion port is in contact with the receiving port. The pipe connection structure according to claim 2. The tightening member includes: a band wound along the outer peripheral surface of the second seating surface portion of the receptacle; and a tightening tool that is attached to a circumferentially open end of the band and tightens the band in a diameter reducing direction. Configured,
A first pressing portion in which the band is wound along an outer peripheral surface of the second seating surface portion with a width dimension of the second seating surface portion or less, and a width of the first pressing portion; 4. The second pressing portion according to claim 2 or 3, wherein the second pressing portion is formed in a substantially C shape in a cross-sectional view from both ends in the direction and has a tapered pressing surface on the inside. Pipe connection structure.   The inner surface of the second seating surface portion pressed in the circumferential direction of the tube by the tightening by the tightening member and the outer surface of the second contact surface portion are formed in a tapered shape. The pipe connection structure according to any one of claims 2 to 4.

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