JPH0519776U - Corrosion-proof flange joint structure - Google Patents

Abstract

(57) [Summary] [Purpose] Corrosion-proof flange joints are more reliably protected from corrosion, and the connecting and connecting postures of unit pipes are firmly held. [Structure] Taper female screw 4 is engraved inside the joint body 5 of the flange joint 1 '', and the pipe end core 8 '' is attached to the flange at the front end.
It is screwed in by 10 'screwing, and the stroke end is restricted by the stopper ring 13 fixed in the groove 12 of the joint body 5,
In addition, a double-sided seal ring 16 at the base is brought into contact with the polyethylene powder lining on the inner surface of the steel pipe 2 to prevent the generation of dead water and the like in the entire water flow region to ensure corrosion resistance, and an epoxy resin lining on the rear surface 19 Apply. [Effect] Prevents the impact of the stopper ring 13 on the rear surface of the flange joint during transportation and assembly, and reliably seals the entire water flow path to improve corrosion resistance, improve product accuracy, and eliminate unnecessary control. Try to finish it.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The disclosed technology belongs to the structural technical field of flange joints such as linings for epoxy resins used for connecting and connecting pipes used for waterworks such as water pipes.

[0002]

[Prior Art]

 As is well known, along with the improvement of civic life, there are remarkable developments of waterworks such as waterworks in both urban and rural areas. Furthermore, not only civilian but also industrial waterworks develops remarkably. Is becoming.

[0003] However, although the water supply for civilian use has the aspect of respecting the health and hygiene of citizen's life, the industrialized supply of sterilized and sterilized fresh water is important. In order to improve the water quality for product cleaning etc., sterilization of chlorine etc., sterilization, and the process of adding an antidote have come to be performed, and the water quality deteriorates over the years due to the restriction to supply in large quantities to meet demand. In view of this, the amount of chlorine added gradually increases, and although this is in itself a desirable thing, once the pipes installed for such water supply are laid, Because of its strong demand for sufficient durability and constant strength, the steel pipe is generally widely used from the viewpoint of strength and rigidity in consideration of corrosion resistance. The piping will corrode over time This is easy, and in order to deal with this, vinyl chloride lined steel pipes and polyethylene powder lined steel pipes have been widely used.

[0006] Thus, although it is originally desirable for the pipe to be a long pipe, it is unavoidable that the length of the pipe is set to a predetermined unit length due to the conditions of the device in manufacturing and the constraints such as transportation to the installation site. At the time of installation in the installation, the mode of connecting the unit length pipes with each other by a joint is designed, and therefore, in order to keep the corrosion resistance of the pipe, the joint must also have a corrosion resistance. Therefore, a joint with vinyl chloride lining or polyethylene powder lining was also used there.However, in the case of conventional joints, when the screw is connected to the pipe, the anticorrosion lining is peeled off and the steel surface is removed. If there is an exposed part, the part will rust over time, which may cause the inconvenience that corrosion resistance will decrease due to the retention of dead water and so on. This has been dealt with by inserting the end cores and screwing them together, and various corrosion-resistant joints have been researched, developed, and put into practical use.

Since the type corrosion-resistant joint is also intended to connect and connect a pair of pipes and the like, corrosion-proofing is required, and the sealing property in a tightened state is required at the time of initial installation. Not only that, it must be sufficiently retained over time, and under the influence of vibration and corrosion due to earthquakes and various construction works in the vicinity over time, the joint itself's sealability, mechanical connectivity, and corrosion resistance are It was found that this was not enough, and in contrast, a flange joint that has a mechanical tightening function so that the pipes can be firmly connected to each other, the tightened state can be maintained, and the sealability and corrosion resistance can be sufficiently maintained. Has come to be newly adopted, and various types are being researched and developed.

For example, in a flange joint 1 as shown in FIG. 5, a taper male thread 3 is screwed into a pipe 2 of a steel pipe whose inner water-passing side has a predetermined corrosion-resistant lining. A joint body 5 having a female thread 4 is integrally provided with a flange 6 on the side opposite to the threaded side of the pipe 2, and a set number of bolt holes 7, 7 ... provided at a predetermined position in the circumferential direction of the flange 6. Mechanically by press-fitting, and the corrosion-resistant pipe end core 8 made of vinyl chloride resin, etc. is press-fitted inside the male screw 3 of the pipe 2 by hammering etc. and initially set. It has been developed as a twin type that is screwed to the joint body 5 of.

Such a type is put into practical use, for example, a so-called “core insertion type” devised in Japanese Utility Model Laid-Open No. 64-31284, etc., and a resin screw portion is integrally molded with a joint main body by injection molding to form a pipe end core. No. 8 was designed to be driven in during on-site assembly, and assembly was also extremely laborious.

However, the conventional flange joint 1 as shown in FIG. 5 has a large number of parts before the on-site assembly and setting, and there is an inconvenience that the quality control is complicated, and the joint flange 5 has a disadvantage. When the pipe 2 of the steel pipe into which the pipe end core 8 is press-fitted is set, the rear surface of the pipe end core 8 does not become flush with the flange 6 as shown in FIG.

Even if the surface of the joint body 5 is coated with, for example, an epoxy resin, the surface of the joint body 5 does not have an anticorrosion function against water and is weak against impact. For example, it is easy to use when piped with a pipe wrench. There was a problem that after-care was complicated, such as the fact that scratches tended to occur, there were negative points, and that after-care was covered with a sealant.

In order to deal with this, a flange joint 1'as shown in FIG. 4 has been developed to form a stopper flange 10 for an inward integral pipe end core 8'on the flange 6 ', and the pipe end core 8' For the mutual sealability of the flange 6'or the corrosion resistance of the flange 6 ', the one with an anticorrosion lining 11 such as epoxy resin on the end surface of the flange 6'is also developed, In the post-manufacturing storage process, transfer process, assembly process, etc., the corrosion-resistant lining 11 may be damaged if an unexpected impact load is applied to the flange 6 ′ due to interference with other things due to mistaken work or the like. However, there is a problem that peeling occurs and not only the sealing property but also the corrosion resistance is deteriorated.

A dedicated jig is required to apply the anticorrosion lining 11, which naturally leads to an increase in cost, and the accuracy control of the film thickness of the anticorrosion lining 11 is extremely troublesome and the product accuracy is high. There is a problem that it is difficult to ensure uniformity.

[0012] In addition to the above-mentioned "core insertion type", for example, there is a so-called "core built-in type" flange joint such as devised in Japanese Utility Model Laid-Open No. 64-11494, and there is a taper inside the flange joint. It has been proposed that a pipe end core is screwed into a screw, and the flange of the flange joint is processed to be flush with the flange.

[0013]

[Problems to be solved by the device]

 However, since this type of flange joint has a flange formed on the pipe end core, it is screwed in from the side opposite to the pipe screwing side, causing damage to the male thread of the pipe end core, resulting in poor sealing. There is a possibility that it may be sufficient, and compared with the conventional method, although mechanical coupling between the flange joints can be achieved, there is a tendency that the sealing performance cannot be sufficiently maintained.

[0014]

[The purpose of the device]

 The purpose of the invention of this application is to solve the problems of the flange joints based on the above-mentioned conventional techniques, and to replace the conventional corrosion-resistant joints, the advantages of the flange joints, which have good connectivity and excellent fixing and tightening properties, are provided. While making full use of the advantages of the corrosion-resistant tube end core, the joints also have sufficient sealing performance, and various functions are made to take advantage of the "core built-in" function that can be assembled and integrated at the time of manufacturing. It is an object of the present invention to provide an excellent corrosion-resistant flange joint structure that is beneficial to the field of fluid distribution technology application in industry.

[0015]

[Means / actions for solving the problems]

 In order to solve the above-mentioned problems, in order to solve the above-mentioned problems, the structure of the invention of this application, which has the scope of the above-mentioned utility model registration request as a gist, is made up of polyethylene pipe powder-lined steel pipe, etc. In order to obtain a set length of pipe by connecting the unit pipes with a flange joint, at the time of pipe end made of vinyl chloride, etc., against the taper female screw engraved inside the joint body of the flange joint, The core is flanged and screwed into the taper female screw, and a sealing ring made of synthetic resin is fitted to the groove formed in the ring-shaped recess on the end surface of the joint body of the flange joint with an adhesive. At the same time as joining, the flange is joined to the pipe end core via the adhesive, the stroke end of the pipe end core is determined and integrated, and then the polyethylene pipe lined unit pipe The threaded portion is screwed into the taper female thread of the joint body, and the pipe end core is covered to ensure corrosion resistance and sealability in the entire area of the flange joint. The lip of the seal ring, which is integrally joined to the ring-shaped groove on each outer peripheral surface of the pipe end core, has a sufficient sealing property against water and the back-up ring function reinforces it to maintain sufficient corrosion resistance. In addition, the flange joints were fastened together with bolts, and technical measures were taken to ensure a strong connection.

[0016]

【Example】

 Next, an embodiment of the invention of this application will be described below with reference to FIGS. 1 to 3.

In the embodiment shown in FIGS. 1 and 2, reference numeral 1 ″ is a corrosion-resistant flange joint, which is the center of the gist of the invention of this application, and in the embodiment, for convenience of illustration, only the right half is shown. Although not shown, the left half (not shown) is made into a twin type, and the unit length polyethylene powder lining steel pipes 2, 2 are connected and joined to each other as a set length pipe for water supply etc. It is a mode in which it has a sufficient anticorrosion property and a sealing property, and is firmly and loosely connected.

Therefore, in the flange joint 1 ″, a taper female screw 4 is formed concentrically from the insertion side of the unit steel pipe 2 so as to taper the taper male screw 3 of the unit steel pipe 2. The taper female thread 3'is engraved on the outer circumference of the flange 10 'at the base end of the tube end core 8' 'made of a predetermined synthetic resin such as vinyl chloride and having an L-shaped cross section. It is screwed into 4 so that the tip of steel pipe 2 can be sealed.

A predetermined adhesive is applied and interposed between the external thread 3 ′ of the flange 10 ′ of the tube end core 8 ″ and the internal thread 4 of the joint body 5.

Then, a ring-shaped concave groove 12 is provided on the rear end surface of the tubular joint body 5 of the flange joint 1 ″, that is, on the side opposite to the threaded side of the steel pipe 2, and is made of vinyl chloride or the like. A stopper ring 13 made of a synthetic resin is fixed in a ring shape by press-fitting, and the flange 10 'of the tube end core 8' 'is screwed into the taper female thread 4 via its male thread 3'. The stroke end is not restricted so that it does not protrude from the flange joint 1 '', and therefore accidental damage before and after mounting the pipe end core 8 '' is avoided.

Although not shown, a ring-shaped packing 14 made of rubber or the like, which is the same as the conventional one, is interposed between the other flange joint 1 ″ on the left side half to prevent water leakage. It is designed to better back up the gap between the two.

By making the outer diameter of the stopper ring 13 larger than the inner diameter of the packing 14, even if the packing 14 is displaced and the surface of the flange 6 ′ is exposed, rusting does not occur.

As shown in FIG. 2, in the tube end core 8 ″, a ring-shaped recessed groove 15 is provided in the base of the shank portion and a rubber seal ring 16 is embedded. The seal ring 16 is, for example, a polyethylene powder lining of a steel pipe 2 in which two ridges 17 and 18 are formed in the front and rear and a front lip 17 is screwed into a taper female screw 4. The lip 18 at the rear part backs up the seal lip 17 at the front part, and the seal lip 17 at the time of screwing into the taper female screw 4 of the steel pipe 2 is abutted against the seal lip 17 to improve the corrosion resistance. It is designed to prevent falling and curling up, function as a backup ring, and maintain sufficient sealing and corrosion resistance.

In the flange 6 ′ of the flange joint 1 ″, bolt holes 7, 7 ... By firmly connecting and connecting the two steel pipes 2 and 2, a reliable sealing connection between the steel pipes 2 and 2 can be maintained and the function of a pipe of a predetermined length can be sufficiently fulfilled, so that the connecting posture can be maintained. Has been done.

Epoxy resin lining 19 is applied to the entire surface of the flange joint 1 '' (at least the front surface in the figure) to provide strength, rigidity and corrosion resistance against unexpected impacts during transportation and storage. It is designed to be held, and the back side is designed to control impact resistance with a rubber packing 14.

In the above-mentioned configuration, the flange joint 1 ″ of the present embodiment is of “pipe end core built-in type”, so that the taper female screw 4 inside the joint body 5 is connected to the base of the pipe end core 8 ″. The male screw 3'engraved on the outer periphery of the flange 10 'integrally molded with the screw is screwed into and screwed into the ring-shaped recessed groove 12 on the rear surface of the joint body 5 and attached to the stopper ring 13 fixed by press fitting. The stroke end is regulated by abutting against each other and set in a predetermined posture in the joint body 5.

Next, bolts 20 are temporarily inserted into the bolt holes 7, 7 on the upper and lower sides of the flanges 6 ′, 6 ′ in the figure to form a bridge, and a packing 14 is inserted between the flanges 6 ′, 6 ′ from the upper side. Insert it.

Then, the packing 14 is lowered, but the temporary fixing bolt 20 prevents the packing 14 from falling. Therefore, the packing 14 is prevented from being displaced, the background of the flange 6 ′ is prevented from being exposed, and rusting is prevented. Stop.

As described above, since the outer diameter of the stopper ring 13 is larger than the inner diameter of the packing 14, rusting of the background of the flange 6 ′ is doubly prevented.

Then, with the pipe end core 8 ″ assembled in the joint body 5, the steel pipe 2 is screwed into the taper female screw 4 of the joint body 5 with the taper male screw 3 and the pipe end core 8 ′. Insert the male thread 3'of the flange 10 'into the female thread 4 so that the seal ring 16 faces the polyethylene powder lining on the inner surface of the steel pipe 2, and the front seal lip 17 is used to make elastic contact. The backup ring 18 thus provided prevents the steel pipe 2 from collapsing in the process of the relative screw connection of the steel pipe 2 so that the sealing property is perfected and the corrosion resistance is maintained.

Further, from the base end side of the tube end core 8 ″, the stopper ring 13, the screw portions 3 ′ and 4 and the adhesive applied to the screw portions are surely sealed.

When the joint connection between the flange joint 1 ″ and the steel pipes 2, 2 is completed, the pair of flanges 6 ′, 6 ′ in that state are pressure-welded to each other via the rubber packing 14. Then, the bolts 20 are inserted into the bolt holes 7 of the flanges 6'and 6'and are tightened by nuts (not shown) to connect and fix them to form a predetermined pipe connection.

Accordingly, the steel pipes 2, 2 of the pair of unit pipes are tightly connected, and the flange joint 1 '' is connected to each of the steel pipes 2 lined with polyethylene powder to ensure the corrosion resistance and It will be guaranteed over time.

Next, in the embodiment shown in FIG. 3, the flange 10 ′ portion of the pipe end core 8 ″ of the embodiment shown in FIGS. 1 and 2 and the corresponding portion of the tapered female screw 4 of the joint body 5, Also, the epoxy resin adhesive 9 is applied in advance to the portion of the stopper ring 13 that corresponds to the groove 12, and these are fixed relative to each other as a whole, so that not only the axial direction but also the circumferential direction does not occur, and the sealing property is improved. In addition, it is a mode in which the corrosion resistance is more surely guaranteed.

It is needless to say that the embodiment of the invention of this application is not limited to the above-mentioned embodiments, and for example, a metal ring or the like is incorporated in the flange of the pipe end core or the stopper ring to improve its strength. It is possible to adopt various modes such as enhancement.

Further, it goes without saying that various packings can be used for design modification.

Of course, the target connecting pipe can be applied to other water supply pipes other than the water pipe.

[0038]

[Effect of the device]

 As described above, according to the invention of this application, a unit steel pipe or the like having a predetermined length with a corrosion-resistant lining, etc. between the units of the pipes used for waterworks, etc., which has been widely spread and is expected to be laid in the future, is basically flanged. By connecting them with each other with a joint, not only the sealability but also the basic effect that the connection posture is made rigid and the strength is improved and the posture can be maintained over time with the seal is provided. The pipe end core is screwed onto the steel pipe in the main body of the flange joint so that it is pre-assembled so that it can be integrated into the assembly site. It is possible to improve yield without needing to do so, and it is possible to avoid loss of the flange joint and the pipe end core, etc., and there is an excellent effect that reliable assembly can be performed accurately as designed.

Therefore, in the invention of this application, a stopper ring for stroke restriction with respect to the pipe end core that is screwed into the entire surface of the joint body of the flange joint is press-fitted or is set by an adhesive agent. Since the pipe end core is inserted and fixed in the joint body in an essentially underhung posture, it is securely connected to prevent the occurrence of so-called dead water on the steel pipe, and more reliable corrosion resistance as a flange joint. There is an effect that can be.

A double triple seal is provided by a pipe end core that is assembled in the flange joint body to prevent the formation of dead water, and packing that is inserted between the stopper ring and the flange joint. Guaranteed and with the added benefit of corrosion protection.

When the pipe is in operation, the polyethylene powder lining on the inner surface of the steel pipe is sealed, and the flange and the stopper ring seal it in a third stage. In addition, since the seal is made by the packing, the flow path of water flows down. There is an effect that the quality assurance is enhanced by sufficiently sealing in another stage and the corrosion due to the generation of red water due to dead water is reliably prevented over time.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional half view of a basic embodiment of the invention of this application.

2 is a cross-sectional view of the tube end core of FIG.

FIG. 3 is a sectional view of the joint body, pipe end core, and stopper ring of another embodiment.

FIG. 4 is a partial half-section view of a flange joint according to the prior art.

FIG. 5 is a partial half sectional view of a flange joint according to another aspect of the related art.

[Explanation of symbols]

 6… Fastening flange 5… Fitting body 2… Piping 4… Tapered female thread 3 ′… Male thread 6… Flange 8 ″… Pipe end core 16… Seal ring 2 ′… Corrosion resistant flange joint 13… Stopper ring 9… Adhesive 14 ... packing

Claims (5)

[Scope of utility model registration request] 1. A pipe having a taper taper thread for pipe connection engraved on the inside of a tubular joint body having a fastening flange and a flange engraved with a male screw threaded to the taper thread. In an anticorrosion flange joint having a pipe end core internally provided with a seal ring that abuts against, the stopper ring of the pipe end core is annularly provided on the side opposite to the pipe connection side of the joint body. Features a corrosion resistant flange joint structure. 2. The corrosion-resistant flange joint structure according to claim 1, wherein the stopper ring is made of resin. 3. A utility model registration claim according to claim 1, wherein an adhesive is interposed between at least the stopper ring and the flange of the tube end core and between the stopper ring and the joint body. Corrosion-proof flange joint structure. 4. A corrosion-resistant flange joint structure according to claim 1, characterized in that a packing is attached to the outside of said stopper ring. 5. The corrosion-resistant flange joint structure according to claim 1, wherein the stopper ring has an outer diameter larger than an inner diameter of the packing.