JPH058169U - Pipe connection parts - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if the thickness of the coating layer of the inner surface coated steel pipe differs considerably due to the difference in the material of the coating layer, the core and the inner surface coated steel pipe are elastically deformed according to the thickness of the coating layer. It is an object of the present invention to provide a pipe connecting part capable of reliably sealing a space. [Structure] An annular seal portion 23, which is brought into pressure contact with a coating layer 42 of an inner surface coated steel pipe 4, is integrally provided at a rear end portion of a body portion 21 of a core 2, and the annular seal portion 23 is provided behind the body portion 21. It is formed in a substantially tongue-shaped cross section that extends rearward from the end portion and is thinner than the wall thickness of the body portion 21 to increase the elastically deformable range and elastic force.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pipe connecting component for preventing rusting at the pipe end portion of the inner surface coated steel pipe when the end portion of the inner surface coated steel pipe is screwed and connected to an inner screw provided on the inner surface of the end portion. Is.

[0002]

[Prior Art]

 At present, the water pipe system that is generally popular is to connect the inner surface coated steel pipe through a joint that is a metal pipe connection component, but at the connection part, that is, the pipe end of the inner surface covered steel pipe. The deterioration of water quality, such as the generation of red water due to rusting, has become a problem. As a solution to such a problem, various structures as disclosed in Japanese Utility Model Laid-Open No. 56-82387, Japanese Utility Model Laid-Open No. 59-160983, etc. have been proposed in the past, but all of them have been proposed. It was not possible to reliably prevent the infiltration of water into the pipe end of the inner surface coated steel pipe, and therefore it was not possible to sufficiently prevent rusting of the pipe end.

Therefore, prior to the present application, the applicant proposed a pipe end corrosion-proof structure for an inner surface coated steel pipe as shown in FIG. 7 disclosed in Japanese Utility Model Laid-Open No. 62-52385. The pipe end portion anticorrosion structure of the inner surface coated steel pipe shown in FIG. 7 includes an annular collar portion 104 which is positioned in front of the end surface 101a of the inner surface coated steel pipe 101 and fixed to the inner surface of the pipe connection component 102 in a watertight manner, A tubular body having an annular lip portion 105a positioned in the inner surface coated steel pipe 101 and press-contacted to the coating layer 101b of the inner surface coated steel pipe 101, and an annular groove 105b adjacent to the annular lip portion 105a. A core 103 made of a synthetic resin, which is integrated with the portion 105, is used. According to the pipe end portion anticorrosion structure of the inner surface coated steel pipe disclosed in Japanese Utility Model Laid-Open No. 62-52385, after the flange portion 104 of the core 103 is fixed to the inner surface of the pipe connection component 102, the inner surface coated steel pipe 101 When the end portion is screwed into the pipe connecting component 102, the lip portion 105a provided on the body portion 105 of the core 103 is pressed against the coating layer 101b of the inner surface coated steel pipe 101 by its elastic restoring force, and the pressure contact portion Ensures that the watertightness is maintained.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned inner surface coated steel pipe, various synthetic resins such as polyethylene, hard vinyl chloride, or polybutene are used as the coating layer 101b depending on the need for heat resistance, corrosion resistance, etc. The thickness of the coating layer 101b differs considerably depending on the type of synthetic resin.

Therefore, in order to cope with the difference in the thickness of the coating layer 101b, the size of the lip portion 105a formed in the middle portion of the outer peripheral surface of the body portion 105 is increased to increase the elasticity of the lip portion 105a. However, in this case, if the size of the lip portion 105a is increased, the amount of protrusion from the outer peripheral surface of the body portion 105 is increased. There arises a problem that the inner surface coated steel pipe 101 having a small inner diameter, in which the layer 101b approaches the outer peripheral surface of the body 105, does not enter or becomes very difficult to enter.

The present invention has been made in view of such circumstances, and it is possible to deal with the inner coating steel pipe even if the coating layers of the coating pipe have considerably different thicknesses. It is an object of the present invention to provide a pipe connection component capable of reliably sealing the space between them.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention is provided with a synthetic resin core integrally having an annular flange and a tubular body inside the pipe connecting part, and the inner surface of the end of the pipe connecting part is provided. An inner thread is provided for threadingly connecting the end of the inner surface-coated steel pipe, and when the inner surface-coated steel tube is threadably connected to the inner thread, the annular collar portion of the core causes the inner surface of the inner-surface coated steel tube to end. In the pipe connection component, the tubular body is positioned in front of the inner surface-coated steel pipe, and the diameter of the rear end of the core body is press-contacted with the coating layer of the inner-surface coated steel pipe. A ring-shaped seal portion that bulges outward in the direction is integrally provided. The ring-shaped seal portion extends rearward from the rear end portion of the body portion and has a substantially tongue-shaped cross section that is thinner than the wall thickness of the body portion. It is characterized by being formed and made elastically deformable.

[0008]

[Work]

 In the case of the present invention, the rear end of the body of the core is integrally provided with an annular seal portion that bulges outward in the radial direction to be brought into pressure contact with the coating layer of the inner surface coated steel pipe. The elastically deformable range and elastic force of the annular seal part are increased by forming the tongue shape in section, which extends rearward from the rear end part and is thinner than the wall thickness of the body part, so that it can be elastically deformed. As a result, even if the coating layer of the inner surface coated steel pipe is a large inner diameter coated steel tube with a relatively large distance from the outer peripheral surface of the body of the core, the annular seal part ensures the coating layer of the inner surface coated steel pipe. It is possible to ensure a tight seal between the core body of the core and the coating layer of the inner surface coated steel pipe by pressing against the inner surface of the core, and the coating layer of the inner surface coated steel pipe approaches the outer surface of the body of the core. Even with coated steel pipes, the annular seal part undergoes large elastic deformation, so The problem that the coated steel pipe did not enter or slipped in was solved, and the annular seal part could be properly pressure-welded to the coating layer of the inner surface coated steel pipe, and the gap between the body of the core and the coating layer of the inner surface coated steel pipe could be Can be reliably sealed.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a state in which a synthetic resin core 2 is attached to a socket type joint 1 which is a pipe connection component.

On the inner surface of the joint 1, tapered inner screws 11, 11 are screwed from both ends to the central part, and a recessed screw is provided between the left and right inner screws 11, 11. The smooth portion 12 is provided. As shown in detail in FIG. 2, a lining layer 3 made of synthetic resin is formed on the screwless portion 12 described above. The lining layer 3 may cover only the non-threaded portion 12, but as shown in the figure, it is extended so as to cover the inner thread portions 11a, 11a of the inner threads 11, 11 on both sides thereof. It is preferable to keep it.

The core 2 has a tubular body portion 21 and an annular collar portion 22 formed integrally with the tip portion thereof. An annular seal portion 23, which bulges outward in the radial direction, is integrally formed at the rear end of the body portion 21. The seal portion 23 is formed so that the outer diameter thereof becomes larger than the inner diameter of the inner surface covered steel pipe 4 described later by bulging, and the seal portion 23 extends rearward from the rear end portion of the body portion 21 and the body portion. It is formed to have a tongue-shaped cross section that is thinner than the wall thickness of 21, and is elastically deformable. Inside the seal portion 23, an annular recess 24 is formed which is open at the rear end surface of the body portion 21 and extends in the axial direction of the body portion 21. In addition, the rear end of the seal portion 23 projects rearward (the arrow Y side in the drawing) from the rear end of the inner peripheral wall 25 in order to increase the inner peripheral surface area of the seal portion 23.

As shown in FIG. 3, a plurality of protruding ribs 26 are provided at equal intervals on the inner peripheral surface of the body portion 21, and the ribs 26 of the body portion 21 and the collar portion 22 of the core 2 are provided. It has increased rigidity. Further, as shown in FIG. 1, the inner peripheral surfaces 2a and 2b at the front and rear ends of the body portion 21 are tapered surfaces having a divergent shape so as to reduce the pressure loss of fluid.

On the other hand, the collar portion 22 of the core 2 is formed with an outer screw 22a on its outer periphery, which is screwed to the inner thread 11a of the inner screw 11 screwed on the inner peripheral surface of the joint 1. ing.

In the core 2 configured as described above, the adhesive 50 or the like is applied to the outer screw 22a of the collar portion 22, or the adhesive 50 or the like is applied to the inner thread ridge portion 11a of the joint 1. Then, the outer screw 22a of the collar portion 22 is screwed into the inner screw 11 of the joint 1 so that the collar portion 22 abuts the lining layer 3 of the joint 1, and the inner thread 11a of the inner screw 11 is screwed. Fix it. When the collar portion 22 of the core 2 is fixed to the joint 1 in this manner, intrusion of water from the screwed portion is prevented, and the lining layer 3 straddles the inner screw 11 as shown in FIG. Then, since the outer peripheral end surface of the collar portion 22 is tightly adhered to the lining layer 3, the intrusion of water into the screwed portion is prevented more reliably.

Reference numeral 4 denotes an inner surface coated steel pipe connected to the joint 1. The inner surface coated steel pipe 4 is formed by forming a synthetic resin coating layer 42 on the inner surface of the steel pipe 41 as shown in FIG. Moreover, a taper-shaped outer screw 43 is screwed on the end thereof. The outer thread 43 of the inner surface coated steel pipe 4 is screwed into the inner thread 11 of the joint 1.

When the inner surface coated steel pipe 4 is screwed into the joint 1 as shown in FIG. 2, the annular seal portion 23 has a large elastic deformation range and elastic force depending on its forming position and shape. Even if the coating layer 42 is thin as shown in FIG. 4 (A) or the coating layer 42 'is thick as shown in FIG. 4 (B), the coating layers 42, 42' are pressed to reduce the diameter. The elastic restoring force of itself presses the coating layers 42, 42 '. Moreover, in the case of this embodiment, since the concave portion 24 inside the annular seal portion 23 opens inside the inner surface coated steel pipe 4, when liquid such as water passes through the inner surface coated steel pipe 4, the seal portion 23 The liquid is pressed against the coating layers 42, 42 ′ by the pressure applied by the liquid on its inner surface, and the pressing force makes a stronger and more reliable pressure contact with the coating layers 42, 42 ′.

It is needless to say that the present invention is not limited to the above-mentioned embodiment. For example, as shown in FIG. 5, a pipe connecting part has a joint 1'in which an inner thread 11 'is formed on the entire inner peripheral surface. It is needless to say that the present invention can also be applied to the one in which a pair of cores 2 and 2 are screwed to the inner screw 11 'as the collar portions 22 and 22 are butted.

Further, as shown in FIG. 6, when the core 2'is mounted on the inner threads 11 and 11 'of the joints 1 and 1', the recess 24 and the seal portion 23 are outwardly moved by a predetermined amount from the opening end faces of the joints 1 and 1 '. You may make it project. By doing so, it is possible to confirm from the outside whether or not the mounted state of the core 2'is proper by confirming the protruding amount of the seal portion 23 protruding from the open end face of the joint 1, 1 ', and it is possible to attach the core improperly. It is possible to prevent rusting.

The pipe connecting component is not limited to the socket type joint, but may be an elbow type or T-shaped joint.

Further, in the above-mentioned embodiment, the respective cores corresponding to the respective openings of the pipe connecting part are provided, but the cores corresponding to the plurality of openings may be integrally formed. ..

Further, in the above embodiment, the outer surface of the flange portion of the core is fixed to the inner surface of the pipe connecting component with an adhesive or the like, but the present invention is not limited to this, and for example, the flange portion of the core. The entire surface side may be fixed in a watertight manner to the bulged inner surface bulged on the inner surface of the pipe connecting component.

[0023]

[Effect of the device]

 As described above, according to the pipe connecting component of the present invention, even if the coating layer of the inner surface coated steel pipe is a large inner diameter coated steel pipe having a relatively large distance from the outer peripheral surface of the body of the core, an annular seal portion is formed. Can be securely pressed against the coating layer of the inner surface coated steel pipe to ensure a tight seal between the body of the core and the coating layer of the inner surface coated steel pipe, and the coating layer of the inner surface coated steel pipe is Even if the inner surface coated steel pipe has a small inner diameter that approaches the outer peripheral surface of the core part, there is no problem that the inner surface coated steel pipe does not enter or does not slip, and the core body and the coating layer of the inner surface coated steel pipe The space between the pipes can be reliably sealed. Therefore, the pipe connecting part of the present invention can be applied to various types of inner surface coated steel pipes having different coating layers.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view showing an assembled state of a joint and a core in an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts in a state where an inner surface coated steel pipe is connected.

FIG. 3 is a side view of the core.

4 (A) and (B) are cross-sectional views of relevant parts for explaining the adaptability of the inner surface coated steel pipes having different thicknesses to the coating layer.

FIG. 5 is a cross-sectional view of main parts showing another example of the joint.

FIG. 6 is a cross-sectional view of main parts showing another example of the core.

FIG. 7 is a cross-sectional view of a main part of a conventional example.

[Explanation of symbols]

 1,1 'Joint (pipe connection part) 2,2' Core 4 Inner surface coated steel pipe 11, 11 'Inner screw 21 Body part 22 Collar part 23 Seal part 42, 42' Inner surface coated steel pipe coating layer

Claims (1)

[Claims for utility model registration] [Claim 1] A synthetic resin core integrally having an annular flange and a tubular body is provided inside the pipe connecting part, and an inner surface of an end of the pipe connecting part is provided. Is provided with an inner thread to which the end of the inner surface coated steel pipe is screwed and connected, and when the inner surface coated steel pipe is threadedly connected to the inner thread, the annular flange portion of the core is an end surface of the inner surface coated steel pipe. In the pipe connecting part, which is located in front of the tubular body and is located in the inner surface-coated steel pipe, the diameter of the rear end portion of the core body is made to press-contact with the coating layer of the inner surface-coated steel pipe. An annular seal portion that bulges outward in the direction is integrally provided, and the annular seal portion extends rearward from the rear end portion of the body portion and has a substantially tongue-shaped cross section that is thinner than the thickness of the body portion. A pipe connecting part, which is formed and elastically deformable.