JP2023102401A - Housing-type pipe joint and pipe joint method using the same - Google Patents

Abstract

To provide a novel housing-type pipe joint which can surely prevent the lowering of seal performance, a fall of a pipe, a rotation phenomenon or the like by tightly connecting a plurality of pieces of piping to each other, and a pipe joint method using the same.SOLUTION: A maximum height from an abutment face of a flange of a housing claw part which abuts on an annular groove of piping is set smaller than a half of an outside diameter of the annular groove of the piping. By this constitution, when assembling a housing to a piping end part, the piping end part can be fastened by being deformed into a substantially-elliptical shape by pressing the annular groove of the piping by the claw part. Since the claw part of the housing thereby strongly bites into the annular groove, the piping end parts are surely connected and fixed to each other, and the lowering of seal performance and a pipe fall phenomenon can be prevented. Also, by the deformation of the end part of the piping into the substantially elliptical shape, a rotation phenomenon of the end part can be surely prevented.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a housing type pipe joint for butting and connecting pipes together in a substantially straight line, and a pipe joint method using the same.

A conventional housing-type pipe joint comprises a pair of arc-shaped housings, a ring-shaped gasket, and a pair of fastening bolts, as shown in Patent Documents 1 and 2 below, for example. Then, pipes having annular grooves or annular protrusions formed in advance at their ends are butted against each other, a ring-shaped gasket is fitted to the outer periphery of the butted portion so as to cover it, and then a pair of housings are attached so as to sandwich the circumference of the gasket from the top and bottom or left and right directions, and then the housings are annularly fastened with a pair of fastening bolts to firmly seal the buttock portion and connect the pipes in a substantially straight line.

JP-A-11-241793 Japanese Patent No. 4378470

By the way, in the conventional housing-type pipe joint, a small gap may be formed between the surface of the pipe and the housing after fastening due to manufacturing errors or thermal deformation of the pipe or housing. In such a case, the piping may bend from the connecting portion due to an earthquake or aged deterioration, and the sealing performance may deteriorate, or in the worst case, the pipe may come off. In addition, if there is a minute gap between the pipe and the housing, one of the pipes may rotate during construction, which may reduce the sealing performance and pressure resistance of the pipe. In addition, the rotation may cause an indicator provided on the pipe or the handle of the connecting valve to be misaligned, making construction difficult or greatly impairing usability.

Accordingly, the present invention has been devised to solve these problems, and its object is to provide a novel housing-type pipe joint that can firmly connect and fix pipes together to prevent deterioration of sealing performance and reliably prevent detachment and rotation phenomena due to improved pressure resistance performance, and a pipe joint method using the same.

In order to solve the above-described problems, a first invention is a housing-type pipe joint for connecting a pair of pipes having a substantially perfect circular cross section with annular grooves formed at the ends thereof, the joint comprising: a ring-shaped sealing member that covers the outer circumference of the pipes so as to cover the butted portion of the pipes; a pair of housings that are attached to the sealing members so as to sandwich them from both sides; and a fastener that connects the housings together. and a pair of claws extending from both ends in the width direction of the housing body toward the center of the arc and abutting against the annular groove of the pipe, and a pair of flanges extending from both ends of the housing body, wherein at least one of the pair of claws has a maximum height from the contact surface of the flange that is smaller than 1/2 of the outer diameter of the annular groove of the pipe.

According to such a configuration, after the pipes are butted against each other, a ring-shaped seal member is put on the outer periphery so as to cover the butted portion, a pair of housings is assembled on the seal member, and then the flanges of the housings are tightened with fasteners to press the annular groove of the pipe with the claw portion of the housing, thereby deforming the end portion of the pipe into a substantially elliptical shape. As a result, since the claws of the housing firmly bite into the annular groove, it is possible to reliably connect and fix the pipes to each other to prevent deterioration of the sealing performance and improve the pressure resistance performance to prevent the detachment phenomenon. In addition, by deforming the end portion of the pipe into a substantially elliptical shape, it is possible to reliably prevent the rotation phenomenon and the like.

A second aspect of the present invention is a housing-type pipe joint for connecting a pair of pipes having a substantially perfect circular cross-section with annular projections formed at the end portions thereof, the pipe joint comprising: a ring-shaped seal member that covers the outer periphery of the pipes so as to cover the butted portion of the pipes; a pair of housings that are mounted on the seal member so as to sandwich the housings from both sides; and a fastener that connects the housings together. The housing type pipe joint has a pair of claws extending from both ends in the width direction toward the center of the arc and abutting against the outer surface of the pipe, and a pair of flanges extending from both ends of the housing body, wherein at least one of the pair of claws has a maximum height from the contact surface of the flange that is smaller than 1/2 of the outer diameter of the pipe.

According to such a configuration, after the pipes are butted against each other, a ring-shaped seal member is put on the outer periphery so as to cover the butted portion, and then a pair of housings is assembled on the seal member, and then the flanges of the pair of housings are tightened with fasteners to press the surfaces of the pipes with the claws of the housings, thereby deforming the ends of the pipes into a substantially elliptical shape. As a result, the claws of the housing firmly bite into the surface of the pipe, so that the pipes can be reliably connected and fixed to each other to prevent deterioration in sealing performance and improve pressure resistance, thereby preventing detachment. In addition, by deforming the end portion of the pipe into a substantially elliptical shape, the rotation phenomenon can be reliably prevented.

A third invention is the housing type pipe joint according to the first invention, wherein the width of the pair of claw portions is equal to or larger than the outer diameter of the annular groove of the pipe. According to such a configuration, the pipe end portion having the annular groove is easily expanded and deformed in the width direction of the claw portion, so that the pipe end portion can be more reliably deformed into a substantially elliptical shape.

A fourth invention is the housing type pipe joint according to the second invention, wherein the width of the pair of claws is equal to or larger than the outer diameter of the pipe. According to such a configuration, the pipe end portion having the annular projection is easily expanded and deformed in the width direction of the claw portion, so that the pipe end portion can be more reliably deformed into a substantially elliptical shape.

A fifth invention is a pipe joint method using the housing type pipe joint of the first or third invention, in which a pair of pipes having a substantially perfect circular cross section and having annular grooves formed at their ends are butted against each other, and then a ring-shaped seal member is put on the outer circumference of the pipes so as to cover the butted portions. A pipe joint method using a housing-type pipe joint, characterized in that the end of the pipe is deformed into a substantially elliptical shape and then fastened.

With such a pipe joint method, since the claws of the housing firmly bite into the annular groove, it is possible to reliably connect and fix the pipes to each other to prevent the deterioration of the sealing performance and improve the pressure resistance performance to prevent the detachment phenomenon. In addition, by deforming the end portion of the pipe into a substantially elliptical shape, the rotation phenomenon can be reliably prevented.

A sixth invention is a pipe joint method using the housing type pipe joint of the second or fourth invention, wherein a pair of pipes having a substantially circular cross section and having annular projections formed at their ends are butted against each other, and then a ring-shaped seal member is placed on the outer periphery of the pipes so as to cover the butted portions, and then a pair of housings are assembled on the seal members so as to sandwich the seal members from both sides. A pipe joint method using a housing-type pipe joint, characterized in that the end of the pipe is deformed into a substantially elliptical shape and then fastened.

With such a pipe joint method, the claws of the housing firmly bite into the surface of the pipe, so that the pipes can be securely connected and fixed to prevent deterioration of the sealing performance and distortion due to elongation of the pipe.

According to the present invention, since the claws of the housing firmly bite into the annular groove or the surface of the pipe, it is possible to reliably connect and fix the pipes to each other to prevent deterioration of sealing performance, detachment, and distortion due to elongation of the pipe. In addition, even if a strong external force is applied by deforming the end portion of the pipe into a substantially elliptical shape, the rotation phenomenon can be reliably prevented. Furthermore, since the housing and its claws do not have a complicated structure, it is possible to suppress an increase in the manufacturing cost.

1 is a longitudinal sectional view showing an embodiment of a housing type pipe joint 100 according to the present invention; FIG. FIG. 2 is a cross-sectional view in the direction of A in FIG. 1; It is explanatory drawing which shows the relationship between housings 20 and 20 and piping P1 and P2. FIG. 4 is a longitudinal sectional view showing a pipe joint process using the housing type pipe joint 100 according to the present invention; 5 is a cross-sectional view in the direction of A in FIG. 4; FIG. It is explanatory drawing which shows the relationship between the housings 20 and 20 and piping P1 and P2 before fastening (pressing). It is explanatory drawing which shows the relationship between the shape of piping P1, P2 before and after fastening, and its diameter, and a cross-sectional area. FIG. 10 is a cross-sectional view of pipes P1 and P2 at a connecting portion using a conventional housing type pipe joint 200; FIG. 10 is a vertical cross-sectional view of pipes P1 and P2 at a connecting portion using a conventional housing type pipe joint 200; FIG. 10 is a longitudinal sectional view showing an example in which a conventional housing type pipe joint 300 is applied to rolled ring type pipes P3 and P4. FIG. 10 is a vertical cross-sectional view showing the influence of fluid pressure when using a conventional housing type pipe joint 300; FIG. 2 is a longitudinal sectional view showing an example in which the housing type pipe joint 100 of the present invention is applied to rolled ring type pipes P3 and P4.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing one embodiment of a housing type pipe joint 100 according to the present invention, and FIG. 2 is a sectional view taken along direction A in FIG. As shown in the figure, the housing type pipe joint 100 connects the ends of a pair of pipes P1 and P2 against each other and substantially linearly, and comprises a ring-shaped seal member 10, a pair of housings 20 and 20, and a pair of fasteners 30 and 30.

The pipes P1 and P2 connected by the housing type pipe joint 100 are metal pipes such as stainless steel having a substantially circular cross section, and are existing pipes installed indoors and outdoors in buildings such as buildings, condominiums, and factories in order to safely distribute high-pressure fluids such as liquids and gases. At the ends of the pipes P1 and P2, an annular groove d having a depth of about 2 to 3 mm and a width of about 6 to 10 mm is formed along the circumferential direction at a portion about 10 to 30 mm from the end by grooving. Although the diameter and thickness of the pipes P1 and P2 are not particularly limited, existing pipes with a diameter of about 40 to 150 mm and a thickness of about 1.0 to 3.0 mm are often used.

A ring-shaped sealing member 10 forming part of the housing type pipe joint 100 is made of elastic rubber, silicon, plastic, or the like, and its inner peripheral surface has a U-shaped cross section facing toward the center. The material of the seal member 10 is changed as appropriate depending on the type of fluid. For example, in the case of piping a fluid containing residual chlorine such as tap water, rubber such as ethylene propylene rubber (EPDM) and acrylonitrile butadiene rubber (NBR) is used.

The housings 20, 20 are composed of an arc-shaped housing body 21, a pair of claw portions 22, 22 extending from both ends in the width direction of the housing body 21 toward the center of the arc, and a pair of flanges 23, 23 extending from both ends of the housing body 21. The arcuate housing body 21 has an accommodating portion 21a having a U-shaped cross section formed on the inner peripheral surface thereof, and the sealing member 10 is accommodated in the accommodating portion 21a. The housings 20, 20 are formed by casting or forging a cast iron material such as FCD450 or a high-strength metal material such as stainless steel (SUS304, etc.) so that a housing body 21, claws 22, 22, and flanges 23, 23 are integrally formed.

Further, as shown in FIG. 3, the arc-shaped claw portion 22 extending from the housing body 21 has a maximum height h from the contact surface 23a of the flange 23 smaller than 1/2 of the outer diameter φ of the annular groove d of the pipes P1 and P2 (h<1/2φ). That is, if the outer diameter of the annular groove d of the pipes P1 and P2 is 100 mm, the maximum height h is less than 50 mm, for example 48-49 mm. Furthermore, as shown in the figure, the width w of the claw portion 22 is larger than the outer diameter φ of the annular groove d of the pipes P1 and P2 (w(φ+α)). That is, similarly, when the outer diameter of the annular groove d of the pipes P1 and P2 is 100 mm, the width w thereof exceeds 100 mm, for example, 101 to 102 mm.

On the other hand, the fasteners 30, 30 consist of a bolt 31 and a nut 32. The bolts 31, 31 are passed through the bolt holes 23b, 23b, 23b, 23b formed in the respective flanges 23, 23, 23, 23, respectively, and the nuts 32, 32 are screwed to connect the housings 20, 20 in an annular shape.

FIGS. 4 to 7 show a pipe joint method using the housing type pipe joint 100 having such a configuration and its action and effect. First, as shown in FIG. 4, the ends of the pipes P1 and P2 are coaxially butted with a predetermined interval (for example, about several mm), and a ring-shaped seal member 10 is placed on the outer periphery so as to cover the butted portion. Next, as shown in FIGS. 4 and 5, a pair of housings 20, 20 are assembled on the seal member 10 so as to sandwich the seal member 10 from both sides (top and bottom in the figure).

After that, the housings 20, 20 are integrated by the fasteners 30, 30, and the state before tightening is as shown in FIG. That is, as shown in FIG. 3, the maximum height h of each of the claws 22, 22 from the contact surface 23a of the flange 23 is smaller than 1/2 of the outer diameter φ of the annular groove d of the pipe P1, as described above. Therefore, as shown in FIG. It is in a formed state.

Similarly, the width w of the claw portions 22, 22 is larger than the outer diameter φ of the annular groove d of the pipes P1, P2 as shown in FIG. Then, when the flanges 23, 23 facing each other are tightened by the fasteners 30, 30 in such a state, the central portions of the respective claw portions 22, 22 strongly press the surface of the annular groove d of the pipe P1 from above and below to bite into the surface and forcibly deform it into a substantially elliptical shape. As a result, the pipes P1 and P2 including the annular groove d can be fastened in a state in which the butted portions of the ends of the pipes P1 and P2 are deformed into a substantially elliptical shape.

FIG. 7 shows the relationship between the cross-sectional shape and cross-sectional area of the pipes P1 and P2 before and after fastening. As shown in FIG. 1A, the pipes P1 and P2 before fastening have a substantially perfect circular cross-sectional shape, and the horizontal diameter φ1 and the vertical diameter φ2 perpendicular thereto are the same 106.1 mm. On the other hand, as shown in FIG. 2B, the pipes P1 and P2 after fastening have a substantially elliptical cross-sectional shape, with a slightly large horizontal diameter φ1 of 108.1 mm and a slightly small vertical diameter φ2 of 104.1 mm. On the other hand, the cross-sectional area before fastening is 8836.9 mm ² and the cross-sectional area after fastening is 8833.8 mm ² , so there is no significant change in the cross-sectional area.

8 and 9 show a joint structure based on a conventional housing type pipe joint 200. FIG. As shown in the figure, of the pair of housings 40, 40 constituting the conventional housing-type pipe joint 200, the claw portions 41, 41 located in the annular groove d are substantially circular like the annular groove d. Therefore, a gap C3 may occur between them due to manufacturing errors or thermal deformation of the housings 40, 40 and the pipes P1, P2. If this gap C3 is very small, no particular problem will occur, but if this gap C3 becomes large, the pipes P1 and P2 will rotate and the sealing function will deteriorate, and usability will deteriorate.

Further, when a large external force is applied to the connecting portion, the gap C3 changes greatly, and as shown in FIG.

In contrast, in the housing type pipe joint 100 of the present invention, as described above, the claws 22 of the housing 20 firmly bite into the surface of the annular groove d, so that the pipes P1 and P2 can be reliably connected and fixed to each other to prevent the deterioration of the sealing performance, and the pressure resistance performance is improved, so that the detachment phenomenon can be reliably prevented. In addition, by deforming the ends of the pipes P1 and P2 into a substantially elliptical shape, even if a strong external force is applied, the rotation phenomenon can be reliably prevented. Furthermore, since the housing 20 and its claw portions 22 do not have a complicated structure, it is possible to suppress an increase in the manufacturing cost.

In the present embodiment, the claw portions 22, 22, 22, 22 of the pair of housings 20, 20 have been described as having substantially semi-elliptical shapes. That is, the rotation phenomenon of the pipes P1 and P2 is caused by the fact that the cross section of at least one of the pipes P1 and P2 maintains a substantially perfect circular shape even after fastening. Therefore, the pipes P1 and P2 do not necessarily need to be deformed into a symmetrical elliptical shape.

Also, as shown in FIG. 3, the width w of the claw portion 22 may be the same as the outer diameter φ of the annular groove d of the pipes P1 and P2. That is, when the outer diameter of the annular groove d of the pipes P1 and P2 is 100 mm, the width w is also set to 100 mm, and only the maximum height h may be reduced (that is, only the vertical diameter φ2 in FIG. 7 is reduced). If the width w of the claw portion 22 is made equal to the outer diameter φ of the annular groove d of the pipes P1 and P2 in this way, it is sufficient to slightly grind the abutting surface of the flange of the existing housing joint. Therefore, the existing one (the width w of the claw portion 22 is slightly larger than the outer diameter φ of the annular groove d of the pipes P1 and P2) can be effectively utilized without preparing a new casting mold.

10-12 show another embodiment of the housing type pipe joint 100 of the present invention. In the above embodiment, the housings 20, 20 for connecting the pipes P1, P2 having the annular grooves d at their ends are used as an example, but as shown in FIG. The conventional housing type pipe joint 300 for connecting the pipes P3 and P4 having such a structure has a housing portion 21a having a U-shaped cross section on the inner peripheral surface of the housing 20, and second housing portions 21b and 21b for housing the annular projections p and p are formed on both sides of the housing portion 21a.

When connecting such pipes P3 and P4, if the cross-sectional shape is substantially perfect circle as described above, one or both of the pipes P3 and P4 may rotate after connection, and in addition, as shown in FIG. Similar to the above, this occurs inevitably due to manufacturing errors and thermal deformation of the pipes P3 and P4 and the housings 20 and 20. However, if the claw portions 22 are formed in a substantially semi-elliptical shape as in the above embodiment, the outer surfaces of the pipes P3 and P4 can be strongly pressed by the claw portions 22 and 22 to deform the ends of the pipes into a substantially elliptical shape for fastening as shown in FIG.

As a result, even with the pipes P3 and P4, which are called rolling rings, the claws 22 and 22 of the housing 20 firmly bite into the outer surfaces of the pipes, so that the pipes P3 and P4 can be reliably connected to each other to prevent deterioration of sealing performance and elongation of the entire length of the pipes due to fluid pressure. In the case of this embodiment as well, if the width w of the housing 20 is made equal to the outer diameter φ of the pipes P3 and P4, as in the case of the above-described embodiment (FIG. 3), the existing ones can be effectively utilized.

DESCRIPTION OF SYMBOLS 100... Housing type pipe joint which concerns on this invention 200, 300... Conventional housing type pipe joint 10... Sealing member 20... Housing 21... Housing main body 21a... Accommodating part 21b... Second accommodating part 22... Claw part 23... Flange 23a... Contact surface 23b... Bolt hole 30... Fastener 31... Bolt 32... Nut 40... Housing 41... Claw part C1, C2, C 3 Gap P1, P2, P3, P4 Piping d Annular groove p Annular projection

Claims (6)

A housing-type pipe joint for butting and connecting a pair of pipes having a substantially circular cross section and having annular grooves formed at the ends thereof,
A ring-shaped seal member that covers the outer circumference of the pipe so as to cover the butted portion of the pipe, a pair of housings that are attached to the seal member so as to be sandwiched from both sides, and a fastener that connects the housings.
At least one of the pair of housings has an arc-shaped housing body curved along the pipe, a pair of claws extending from both ends in the width direction of the housing body toward the center of the arc and contacting the annular groove of the pipe, and a pair of flanges extending from both ends of the housing body,
A housing type pipe joint, wherein at least one of said pair of claw portions has a maximum height from said flange abutment surface smaller than 1/2 of the outer diameter of said annular groove of said pipe. A housing-type pipe joint for butting and connecting a pair of pipes having a substantially circular cross section and having annular protrusions formed at the ends thereof,
A ring-shaped seal member that covers the outer circumference of the pipe so as to cover the butted portion of the pipe, a pair of housings that are attached to the seal member so as to be sandwiched from both sides, and a fastener that connects the housings.
At least one of the pair of housings has an arc-shaped housing body curved along the pipe, a pair of claws extending from both ends in the width direction of the housing body toward the center of the arc and contacting the outer surface of the pipe, and a pair of flanges extending from both ends of the housing body,
A housing type pipe joint, wherein at least one of said pair of claw portions has a maximum height from said flange abutment surface smaller than 1/2 of the outer diameter of said pipe. The housing type pipe joint according to claim 1,
A housing type pipe joint, wherein the width of the pair of claw portions is equal to or larger than the outer diameter of the annular groove of the pipe. In the housing type pipe joint according to claim 2,
A housing type pipe joint, wherein the width of the pair of claws is equal to or larger than the outer diameter of the pipe. A pipe joint method using the housing type pipe joint according to claim 1 or 3,
A pair of pipes having a substantially circular cross section with annular grooves formed at the ends are butted against each other, and then a ring-shaped sealing member is put on the outer periphery so as to cover the butted portion,
assembling a pair of housings on the seal member so as to sandwich the seal member from both sides;
After that, the flanges of the pair of housings are tightened with a fastener, and the annular groove of the pipe is pressed by the claws of the housing to deform the end of the pipe into a substantially elliptical shape for fastening. A pipe joint method using a housing type pipe joint. A pipe joint method using the housing type pipe joint according to claim 2 or 4,
After a pair of pipes having a substantially circular cross section and having annular projections formed at their ends are butted against each other, a ring-shaped sealing member is put on the outer periphery so as to cover the butted portion,
assembling a pair of housings on the seal member so as to sandwich the seal member from both sides;
After that, the flanges of the pair of housings are tightened with a fastener, and the outer surface of the pipe is pressed by the claws of the housing to deform the end of the pipe into a substantially elliptical shape for fastening. A pipe joint method using a housing type pipe joint.

Images