JPH10281364A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and firmly connect pipes to each other without depending on a bolt and welding. SOLUTION: In a plurality of parts in a peripheral direction of an end part where a first/second pipes 21, 31, which must be connected, are opposed to each other, axial direction protrusions 22, 32 respectively mutually fitted in tenon shape are provided, also a base end part of these protrusions 22, 23 is formed in a groove 34 overlapping a tip end part of mate side protrusion in a diametric direction, and in a groove bottom part of at least one pipe, a recessed part 35 is provided. In a protrusion inner surface of the other pipe, a hook 26 or the like capable of engaging with the recessed part 35 is provided, so that pipe mutual connection can be performed by only positioning work in a peripheral direction of a joint part and work loading suitable compressive force in a pipe axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint capable of easily and firmly connecting pipes to each other without using bolts or welding.

[0002]

2. Description of the Related Art Examples of conventional pipe joints include welded joints and mechanical joints as disclosed in, for example, Japanese Patent Application Laid-Open No. 55-123080. this house,
The welded joint is one in which beveling is performed on the pipe end in advance, and welding is performed at an appropriate route interval on site to integrate the pipes with each other, and welding of multiple layers is repeated according to the pipe thickness. In some cases, preheating and stress annealing are performed, and then nondestructive inspection and rust prevention treatment are performed.

FIG. 5 is a cross-sectional view showing the structure of a main part of a mechanical joint disclosed in the above publication.

In this conventional mechanical joint, a lock ring 3, a backup ring 4, and a seal packing 5 are sequentially mounted on an outer periphery of a tube 1 located inside a joint portion of the tubes 1 and 2 to be connected. 1 is inserted into the joint of the pipe 2. An annular projection 6 for regulating the axial position of the lock ring 3 is formed on the inner surface of the joint portion of the pipe 2, and a taper 7 is provided at an inner peripheral edge of the pipe end. A taper 5a is also formed on the outer periphery of the seal packing 5, and the taper 5a and the taper 7 on the pipe 2 side and the taper formed on the contact surface between the lock ring 3 and the backup ring 4 provide a wedge effect at the time of fastening. It is working.

Therefore, the bolt 8 is attached to the flange 8 of the pipe 2.
When the pressing ring 12 is fastened via the nuts 9 and 11, the seal packing 5 and the backup ring 4 are pressed in the axial direction by the pressing ring 12, and a wedge effect is exerted. At this time, the seal packing 5 is also pressed from behind by the backup ring 4 and is pressed between the tubes 1 and 2 to enhance the sealing effect. The ring 13 prevents the tube 1 from coming off the tube 2.

[0006]

However, in the case of the above-described welded joint, manual welding requires a welder, and a welding machine is required for automation. In any case, including inspection after welding and rust prevention treatment, welding one ring requires much time and cost. More rain in the area,
Consideration must be given to the wind, etc., in which case the working efficiency is reduced.

In a conventional mechanical joint, a lock ring 3, a backup ring 4, a seal packing 5,
The number of parts, such as the bolts and nuts 9, 11, the pressing ring 12, and the retaining ring 13, is large, and there are many steps in joining the pipes, which requires time and effort.

An object of the present invention is to make it possible to easily and firmly join pipes without using bolts or welding.

[0009]

According to a first aspect of the present invention, there is provided a pipe joint which is fitted in a plurality of mortise-like manners at a plurality of circumferential ends of opposed ends of first and second pipes to be connected. Along with providing axial projections that fit together, the base end between these projections is formed in a groove in which the distal end of the mating projection overlaps in the radial direction, and a recess is provided in the groove bottom of at least one tube. ,
A hook which can be engaged with the recess is provided on the inner surface of the projection of the other tube. In the first aspect of the present invention, the joint portion may be manufactured separately from the pipe and joined to the pipe by welding or may be formed integrally with the pipe. In any case,
Produced in advance at the factory stage. The joint of pipes on site is
First, position the protrusions in the circumferential direction so that the protrusions are located in the grooves on the mating side. I do. As a result, the inner surface of the projection moves on the bottom surface of the groove,
The hooks of the projections reach the recesses of the groove, and when they engage, the tubes are firmly joined together.

[0010] Further, the pipe joint according to claim 2 of the present invention,
Hooks are provided on the inner surfaces of the projections of the first and second tubes, respectively, and recesses are formed at the bottoms of the grooves of the first and second tubes so as to be engageable with the hooks on the other side. According to the second aspect of the present invention, since the opposite ends of the joint are engaged with each other to grasp the mating side, the joint strength of the joint is increased, the robust pipe connection is enabled, and the reliability is improved.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a side view including a partial sectional view showing a connection state of a pipe joint according to an embodiment of the present invention, FIG. 2 is an external view showing a connection state of the joint parts, and FIG. 3 is a detail view of the joint part. FIG. 4 is a front view as seen from the direction of arrows AA in FIG. Here, a description will be given of an example in which each joint portion has basically the same configuration. Therefore, only one joint is shown and described in detail.

The pipe joint according to the present embodiment has an axial projection 2 which is fitted in a mortise form at a plurality of circumferential positions at opposite ends of a first pipe 21 and a second pipe 31 to be connected.
2 and 32, and the first and second tubes 21 and 3
The groove 34 (second groove) in which the distal ends 23 and 33 of the mating protrusions overlap in the radial direction with the base end between the protrusions
(Only the tube side is shown). Further, a recess 35 is provided at the bottom of each groove 34, and hooks 26, 36 engageable with the recess 35 of the groove 34 are provided on the inner surface of the distal end of a mating projection fitted into each groove 34, respectively. It is.

This will be described in more detail.
Reference numeral 0 denotes a step formed on the inner surface of each of the projections 22 and 32, and the end faces 27 and 37 of each step are continuous in the circumferential direction, and the end faces 27 and 37 abut upon connection. An annular groove 38 is formed in the end face of one joint, that is, the end face 37 of the joint 30 on the side of the second pipe 31, and an O-ring 41 is mounted in the annular groove 38, thereby providing airtightness or liquid tightness. We can secure it.

As shown in FIGS. 2 and 3, the grooves 34 of the joints 20 and 30 are formed such that the groove bottoms are inclined radially outward from the end surfaces 27 and 37 of the respective stepped portions toward the base end side. And the projections 22 and 3 overlapped with the respective grooves 34.
2 is also set so that each radial thickness becomes thinner from the base end side to the tip end side. Therefore, each groove 3
4 are connected to the joints 20 and 30 when the joints 20 and 30 are joined.
It functions as a guide for smoothly leading the engaging members 2 and 32 to the engaging portion.

In the pipe joint of this embodiment, the pipe 2
In order to join the joints 1 and 31 to each other, first, the projections 22 and 32 of the joints 20 and 30 are positioned in the circumferential direction so as to be positioned in the groove 34 on the mating side.
2, 32 hooks 26, 36 are recesses 3 of groove 34 on the other side.
Appropriate compressive force is applied in the tube axis direction until it engages with 5.
Thereby, the inner surfaces of the projections 22 and 32 are guided by the bottom surfaces of the grooves 34 and move, and the hooks 26 and
36 reach the recesses 35 of each groove 34, which are joints 2
When engaged at both ends of 0,30, the tubes are firmly joined together.

As described above, in the pipe joint according to the present embodiment, the work of positioning the joint portions 20 and 30 in the circumferential direction and applying an appropriate compressive force in the pipe axis direction are performed without using any connecting parts such as bolts. Since the pipes are joined to each other only by performing the work, labor on-site work can be saved and the local construction cost can be greatly reduced.

The projections 22, 3 of the joints 20, 30
2 are provided with hooks 26 and 36, and joints 20 and
A recess 35 that can be engaged with the mating hook is formed in each groove 34 of the mating portion 30, and the mating portions 20 and 30 are configured to engage with each other at both ends to grasp the mating side. , 3
0, the connection strength is increased, and a robust pipe connection is made possible, thereby improving the reliability.

In the above-described embodiment, the joints 20,
Although the hooks of the projections 22 and 32 and the recesses 35 of the grooves 34 are engaged with each other at both ends of the joint 30, the protrusions are formed only at one end of the joints 20 and 30. May be configured so that the hook of the groove and the recess of the groove engage,
Even in this case, sufficient connection strength can be obtained.

[0019]

As described above, according to the first aspect of the present invention, each of the first and second pipes to be connected is fitted in a plurality of mortise-like shapes at a plurality of circumferentially opposite ends. Along with providing axial projections, the base end between these projections,
The tip of the mating projection is formed in a groove that overlaps in the radial direction,
A recess is provided at the bottom of the groove of at least one tube, and a hook is provided on the inner surface of the projection of the other tube so as to be able to engage with the recess. Without the need for welding, and without the need to weld in the circumferential direction of the joint, and by applying only an appropriate compressive force in the axial direction of the pipe.
The on-site construction costs were significantly reduced.

According to the second aspect of the present invention, hooks are provided on the inner surfaces of the projections of the first and second tubes, respectively, and the hooks can be engaged with the mating hooks at the groove bottoms of the first and second tubes. The joints are designed to engage each other on both ends of the joint and to grasp the mating side, increasing the joint strength of the joint, enabling a robust pipe connection and improving reliability. Can be improved.

[Brief description of the drawings]

FIG. 1 is a side view including a partial sectional view showing a connection state of a pipe joint according to an embodiment of the present invention.

FIG. 2 is an external view showing a connection state of the pipe joint according to the embodiment.

FIG. 3 is a side view showing details of a joint portion of the pipe joint according to the embodiment.

FIG. 4 is a front view as seen from the direction of arrows AA in FIG. 3;

FIG. 5 is a cross-sectional view showing a configuration of a main part of a conventional mechanical joint.

[Explanation of symbols]

 21 First tube 22, 32 Projection 23, 33 Tip of projection 26, 36 Hook 31 Second tube 34 Groove 35 Recess at bottom of groove

Claims (2)

[Claims] An axial projection is provided at a plurality of circumferential locations at opposite ends of first and second pipes to be connected, each of which includes a tenon-shaped fitting, and a proximal end between the projections. Is formed in a groove in which the tip of the mating projection overlaps in the radial direction, and a recess is provided in the groove bottom of at least one tube, and the recess can be engaged with the recess on the inner surface of the projection of the other tube. Pipe fitting characterized by providing a special hook. 2. The method according to claim 1, wherein hooks are provided on the inner surfaces of the projections of the first and second tubes, respectively, and recesses are formed at the bottoms of the grooves of the first and second tubes so as to be able to engage with the hooks on the other side. The pipe joint according to claim 1, wherein