JP3681339B2 - Pipe end anticorrosion core fixing ring and fixing structure using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used for a turbulent pipe (cut pipe) necessary for constructing a pipeline, and particularly relates to a fixing ring of a corrosion prevention core on a metal pipe cut pipe end face used for water supply and the like and a fixing structure thereof. is there.
[0002]
[Prior art]
Conventionally, when ductile cast iron pipes are buried in the ground and pipes are laid, the entire pipe is protected by painting and lining, and as shown in FIG. It is common to insert and insert two insertion openings 2a. At this time, as shown in the figure, in the NS type joint provided with earthquake resistance, the lock ring 3 is provided on the inner surface of the receiving port 1a, and the projection 4 gets over the lock ring 3 as shown by the chain line in the figure. Insert the insertion slot 2a. In the figure, 5 is a packing and 6 is a lining.
[0003]
In the laying of this pipe line, there is a case where the pipe 2 is not always connected only by a fixed-size pipe, but the pipe 2 must be cut and joined so as to have a predetermined length at the construction site. When the tube 2 is cut in this way, the coating is peeled off and the background is exposed on the tube end surface that becomes the cut surface, so that the anticorrosion function is impaired and red water or the like is generated. Therefore, in general, the anticorrosion coating is applied again to the end face after the cut tube to perform the anticorrosion. However, when anticorrosion paint is applied to the end face after the cut tube and the anticorrosion is applied again, it takes time to dry in cold weather, and it is difficult to apply in places where running water does not stop completely, such as switching work. There is a problem that it is difficult to work.
[0004]
For this reason, as a method other than applying the anticorrosion paint to the end face after the cut tube, there is a method of sealing the exposed portion using the anticorrosion core 7, as shown in FIG. Since this anticorrosion core 7 is made of an elastic body such as rubber, it is held by its elasticity. However, as shown in Japanese Patent Laid-Open No. 7-139686, etc. There is a type of fixing the anti-corrosion core 7 from the inner surface by a diameter expansion force by fitting the fixing ring 10 of the open side to the groove 8.
[0005]
[Problems to be solved by the invention]
However, since the fixing ring 10 fixes the anticorrosion core 7 with a large opening force, the expansion force is attenuated due to deterioration of the material of the fixing ring 10 over time, and the anticorrosion function is maintained. There is a problem that there is a limit to continuing to do so and the reliability is low.
[0006]
In addition, when burying pipes, the excavation method, propulsion method, which is appropriately selected as the pipe laying method based on the use conditions such as external pressure due to earth covering, earth pressure due to road load, internal pressure, topography, geology, traffic volume, Considering the laying method such as the shield method, the service life, etc., the type of pipe to be used will be selected by considering the technical and economic aspects.
[0007]
At this time, depending on the selected pipe type, the inner peripheral length of the pipe varies depending on the pipe thickness difference and the pipe thickness tolerance at the time of manufacture even if the same nominal diameter is used, for example, the first and third pipes. Become. It is preferable that the same fixing ring 10 can cope with the change in the inner circumferential length of the pipe.
[0008]
This invention makes it a subject to make it easy to respond | correspond to the change of pipe inner peripheral length while suppressing aged deterioration of diameter expansion force as much as possible.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention firstly provides a diameter reduction preventing function between both ends of a part of the fixing ring. With this function, regardless of whether the fixing ring is open or not, the degree of attenuation of the diameter expansion force over time is moderate as compared with the conventional one.
[0010]
Next, according to the present invention, the corresponding range of the diameter reduction preventing function is widened to cope with the change in the inner peripheral length of the pipe.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
As an embodiment according to the fixing ring of the present invention, the anticorrosion core is provided on the inner surface of the tube end portion, and is provided over the entire inner surface of the cylindrical portion inserted into the inner surface of the tube end portion of the tube end anticorrosion core. In the fixing ring that is pressed and fixed, it is possible to adopt a configuration in which the locking piece at the other end is inserted into one end and the locking piece is folded back in one circumferential direction. In this configuration, when the locking piece is folded back, the bent portion and the edge of the through hole are locked, and the function of preventing the diameter reduction of the fixing ring is achieved.
[0012]
In this configuration, a narrow neck portion is formed at one end of the fixing ring, and one end of the fixing ring is slidably inserted into a long hole in the circumferential direction of the fixing ring at the other end through the neck portion. If the width of the fixing ring is wider than that of the long hole and is prevented from coming off, the expansion / contraction diameter of the fixing ring is smoothly adjusted by the movement of one end of the fixing hole in the long hole. That is, the movement becomes a guide.
[0013]
Furthermore, if a plurality of insertion holes for the locking pieces are formed, it is easy to cope with a change in the inner peripheral length of the pipe by appropriately selecting the holes. Further, when the diameter expansion hole is formed, if the number of holes is three or more in total, the inner diameter of the pipe can be selected by appropriately selecting two of the three or more holes in the diameter expansion action. It becomes easy to cope with the change.
[0014]
The fixing ring configured as described above is fitted over the entire inner circumference of the cylindrical portion inserted into the inner surface of the tube end portion of the tube end anticorrosion core, the both ends thereof are overlapped, and one end is connected to the other end via the neck portion. The locking piece at the other end is inserted through the long hole and prevented from coming off, and is inserted through the hole at one end to expand the diameter, and then folded and attached.
[0015]
【Example】
FIG. 5 is a front view showing a fixing ring having the function of preventing diameter reduction of the present invention. This fixing ring 10 is a 10% form conventionally used, and a tip 11 having a notch on the A side. The other end 13 on the B side is formed with a long hole 14 that crosses the neck portion 11 a of the tip 11 and a locking piece 15 that is inserted into the hole 12. Reference numeral 16 denotes a diameter expansion hole provided for expanding the fixing ring 10 using a snap ring pliers 20 or the like so as to be fitted into the pipe end anticorrosion core 7. The material of the fixing ring 10 is preferably a springy stainless material, but is not particularly limited to a material having no springiness.
[0016]
4 and 6 are perspective views showing the attachment procedure of the fixing ring 10, and the anticorrosion core 7 is generally used, and a projection (projection) 9 for fitting the fixing ring 10 on the inner surface is provided. Is provided. The number of the projections 9 is arbitrary, and the upper surface thereof is a tapered surface 9a having a downward slope from the fixing ring 10 side toward the inner surface of the anticorrosion core 7, and the fitting of the fixing ring 10 is smoothly performed by the tapered surface 9a. The flow of water or the like is also smoothly guided. At this time, the height of the protrusion 9 and the inclination angle of the taper surface 9a are arbitrary as long as the positioning (removal prevention) and fitting of the fixing ring 10 can be made smooth. It is preferable that the thickness is equal to or lower than the thickness of the fixing ring 10, but it may be higher than the thickness of the fixing ring 10 in consideration of detachment.
[0017]
The anticorrosion core 7 is fixed by the fixing ring 10 after the fixing ring 10 is first circular as shown in FIG. 6 (a), and then the tip 11 is put on the elongated hole 14 as shown in FIG. 6 (b). The locking piece 15 is inserted into the hole 12 so that the outer diameter of the ring 10 is smaller than the inner diameter of the core 7, and the fixing ring 10 is placed between the protrusions 9 on the inner surface of the core 7, as shown by the solid line from the chain line in FIG. Using a simple jig such as a snap ring pliers 20 or a vise, the fixing ring 10 is expanded on the inner surface of the core 7 (see FIG. 6B), and the locking piece 15 being seen from the hole 12 is shown in FIG. Bending as shown in FIG. 6C and fixing the fixing ring 10 so as not to shrink in the circumferential direction.
[0018]
At this time, as shown in FIGS. 7 to 9, even if the pipes have the same outer diameter, the inner peripheral length differs depending on the pipe thickness t. The insertion hole 12 of the stop piece 15 is appropriately selected. For example, when the tube thickness t shown in FIG. 7 is large, the diameter is increased by the holes 16, 16 at the outermost end, and the locking piece 15 is inserted through the outer hole 12 and bent (the folding line a). ). When the tube thickness t shown in FIG. 8 is standard and the tube thickness t shown in FIG. 9 is small, the diameter is increased by the inner holes 16, and the locking piece 15 is formed by the inner hole 12 (FIG. 8). Or, instead of the hole 12, it is inserted into the diameter expansion hole 16 (FIG. 9) and adjusted at the position of the bending point a. In FIG. 9, the reason why the locking piece 15 is inserted into the diameter expansion hole 16 is that if the locking piece 15 is inserted into the insertion hole 12 and bent, the locking piece 15 protrudes from the hole 12 for a long time and there is a problem. In this embodiment, FIG. 10 (a) shows the respective modes at the minimum inner diameter and FIG. 10 (b) at the maximum inner diameter. From this, the adjustment width L of the fixing ring 10 can be obtained.
[0019]
In addition to preventing the core 7 from falling off due to water flow by mounting the fixing ring 10 on the inner surface of the core 7 in this way, the tip 11 is put on the elongated hole 14, thereby the length of the elongated hole 14. The ring 10 can absorb the tolerance of the circumference of the inner diameter of the tube, and the ring 10 can be smoothly fixed to the core 7, and the locking piece 15 prevents the diameter reduction over a long period of time and firmly fixes the core 7 to the end of the tube to prevent red water. To do.
[0020]
FIG. 11 shows another embodiment of the insertion hole 12 and the diameter-enlarging hole 16, wherein (a) shows a single diameter-enlarging hole 16 on one end side, and (b) shows an insertion inside the neck portion 11a. The common hole 12 and the diameter-enlarging hole 16 are used together, and (c) is the same, but the square holes 12 and 16 are used. Thus, the number, position, and shape of the insertion hole 12 and the diameter expansion hole 16 are arbitrary as long as they can function.
[0021]
In FIG. 12, a lightening 17 is formed, and the shape of the lightening 17 is arbitrary such as a long hole (FIG. 1A), a circular hole (FIG. 1B), a square hole, or the like. . This lightening 17 is for facilitating bending of the fixing ring 10, and therefore, the number and position are set to that extent. If it becomes easy to bend, it is advantageous if the inner peripheral length is shortened (in the case of a small-diameter pipe).
[0022]
The long hole 14 is preferably made long to cope with the change in the inner peripheral length as long as there is no problem in strength or the like, but it can also be constituted by a plurality of long holes. However, in this case, since the one end 11 cannot move between the holes, adjustment is impossible.
[0023]
By the way, if the position and length of the locking piece insertion hole 12 and the locking piece 15 are set so as to match the minimum circumferential length, the bent portion is excessively long at the maximum circumferential length so that it matches the maximum circumferential length. If it is set to, the locking piece 15 may not reach the hole 12 and cannot be bent. At this time, in order to be able to cope with both, it is only necessary to lengthen the locking piece 15 or lengthen the insertion hole 12, but the bent portion at the time of the maximum circumference is too long and protrudes into the tube. This causes problems such as trouble when passing through the polypig. If a plurality of insertion holes 12 are provided, optimal locking is possible according to the degree of diameter reduction of the fixing ring 10 (depending on the tube type), and the problem is solved.
[0024]
As shown in FIG. 13, when the rising wall 16a is formed around the diameter expansion hole 16, the wall 16a is reinforced when the ring 10 is expanded or contracted by a jig such as the snap ring pliers 20 or the like. The jig 20 is difficult to be removed from the hole 16, and the operation is smooth. The wall 16a may be formed by cutting and raising when the hole 16 is formed. If the wall 16a is an inclined wall as shown in FIG.
[0025]
Moreover, it can replace with the diameter expansion hole 16, and can also be used as a latching protrusion. For this reason, the “expansion hole 16” referred to in the claims includes a “locking protrusion”. For example, as shown in FIGS. 14A to 14C, a projection 18 bulged in an arc shape can be adopted, and this projection 18 is engaged with the jig 20 as shown in FIG. To do. At this time, the locking hole 18a of the jig 20 may be formed in the protrusion 18 as shown in FIG.
[0026]
Needless to say, the fixing ring 10 according to the present invention may employ a mode of fitting into the groove 8 as shown in FIG.
[0027]
【The invention's effect】
As described above, since the present invention provides the fixing ring with the function of preventing the diameter reduction, the aging degradation of the diameter expansion force of the fixing ring is also suppressed, and therefore, the sufficient adhesion to the tube end of the waterproof core has also been maintained for many years. It is maintained over a long period of time, and red water can be prevented over a long period of time.
[0028]
Moreover, since the insertion hole of the latching piece was made into two or more, it is easy to respond | correspond to the change of pipe inner peripheral length. At this time, if a plurality of diameter expansion holes are provided, it is easy to cope with a change in the inner peripheral length of the pipe in the diameter expansion action.
[Brief description of the drawings]
1 is a perspective view of an essential part of one embodiment. FIG. 2A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 1B is a cross-sectional view taken along line BB. Core installation explanatory diagram [Fig. 4] Mounting action diagram of fixing ring of the same embodiment [Fig. 5] Plan view of one embodiment of the fixing ring [Fig. 6] Mounting action diagram of the fixing ring [Fig. Fig. 8 Mounting action diagram of the fixing ring. Fig. 9 Mounting action diagram of the fixing ring. Fig. 9 Mounting action diagram of the fixing ring. Fig. 10 Mounting action diagram of the fixing ring. FIG. 12 is a plan view of each embodiment of another fixing ring. FIG. 13 is a cross-sectional view of an essential part of each of the other embodiments. FIG. 15] Cross-sectional view of the main part of the pipe joint [Fig. 16] Enlarged cross-sectional view of the main part of the pipe insertion opening
1, 2 Tube 1a Receptor 2a Insert 7 Corrosion-proof core 9 Fixing ring positioning projection 10 Corrosion-proof core fixing ring 11 One end (tip) of the fixing ring
11a One end neck portion 12 Locking piece insertion hole 13 The other end 14 of the fixing ring 10 Long hole (long hole)
15 Locking piece 16 Diameter expansion hole 18 Locking protrusion 20 Snap ring pliers (diameter expansion jig)

Claims (3)

A fixing ring 10 is provided over the inner circumference of the cylindrical portion inserted into the inner surface of the tube end portion of the tube end anticorrosion core 7 and fixes the anticorrosion core 7 by pressing the cylindrical portion against the inner surface of the tube end portion. ,
In the circumferential direction, one neck 11 is formed with a narrow neck portion 11a, and a plurality of holes 12 are formed in the length direction on the other end 13 side from the neck portion 11a. The end 13 is formed with a long hole 14 which is long in the circumferential direction of the fixing ring 10 into which the end 11 is slidably inserted through the neck portion 11a and is inserted into the hole 12 of the end 11. 11 is provided with a locking piece 15 extending to the side, and the width of the one end 11 is wider than that of the long hole 14 to prevent the locking piece 15 from being inserted, and the locking piece 15 is inserted into the hole 12 and folded back. Therefore, the fixing ring of the pipe end anticorrosive core is provided with the function of preventing the diameter reduction of the fixing ring 10. 2. The fixing ring of a pipe end anticorrosion core according to claim 1, wherein ring expansion diameter holes 16 are formed at both ends, and three or more holes 16 at both ends are formed in total. The fixing ring 10 according to claim 1 or 2 is fitted in a press-contact state over the entire inner surface of the cylindrical portion inserted into the inner surface of the tube end portion of the tube end anticorrosion core 7, and both ends 11, 13 of the fixing ring 10 are The one end 11 of the other end 13 is inserted into the long hole 14 of the other end 13 through the neck portion 11 a and is prevented from coming off, and the locking piece 15 of the other end 13 is inserted into the hole 12 of the one end 11. A structure for fixing a pipe end anticorrosion core, which is folded and provided with a function of preventing the diameter reduction of the fixing ring 10 by the folding.

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