Butterfly valve hot tapping branch device and hot tapping branch method using same

Abstract

A hot tapping branch device of the present invention comprises: a fitting installed on a main pipe; a butterfly valve body installed on a flange of the fitting; a disk transfer unit for transferring a butterfly disk to the inside of the butterfly valve body; and a rotary pin insertion unit for inserting a rotary pin for fixing the butterfly disk to the butterfly valve body. A branch pipe, in which a butterfly valve is installed, is installed in a main pipe, thereby significantly reducing a construction period for installing the branch pipe with relatively low costs, compared to conventional line stopping methods.

Description

Butterfly valve non-interruptible branch device and non-interruptible branch method using the same

[0001] The present invention relates to a butterfly valve non-interruptible branch device and a non-interruptible branch method using the same, and more specifically, to a butterfly valve non-interruptible branch device that installs a branch pipe in a main pipe without a single branch pipe, and a non-interruptible branch method using the same.

[0002] In order to supply fluids, including tap water, pipes are buried underground, and by continuously connecting pipes of a certain length, the fluids are safely transported to the desired destination.

[0003] Among these pipes, water supply pipes are composed of large-diameter main pipes that transport large quantities of water over long distances, and branch pipes that branch off from the main pipes and are used for relatively short-distance transport to supply water to buildings such as homes and offices.

[0004] In pipes with branches like this, valves must be installed to ensure that the water supply can be shut off, making it easier to replace aged pipes (main pipe, branch pipe) or valves by simply cutting the water supply.

[0005] This conventional method has the disadvantage of having a wide range of water cutoffs because it is performed after closing all valves installed around the replacement point to cut off the water supply to the pipes or valves at the replacement point.

[0006] In addition, as mentioned above, when the water supply is cut off, it causes inconvenience and loss to each household and various industrial facilities, and there is a problem of causing inconvenience to the lives of the people. In order to solve this problem, a water supply interruption method using a water interruption valve to repair water pipes without cutting off the water supply has been developed.

[0007] This method of continuous operation refers to the process of replacing pipes or valves or connecting or branching separate branch pipes while maintaining the flow and pressure of fluids such as water, gas, and oil flowing in the pipes of the construction section without interrupting them.

[0008] Among these non-perforated methods, most branch pipe installations are done using a method called ‘non-perforated perforation.’

[0009] Such 'uninterrupted perforation' is disclosed in the 'water valve for uninterrupted perforation' of the following patent document 1, and a technology is disclosed regarding a uninterrupted perforation method for performing the connection work without blocking the fluid (water) flowing in the main pipe when connecting a branch pipe of the same diameter or smaller to the main pipe through which the fluid flows, such as a water supply pipe, a drainage pipe, a water supply pipe, or a sewage pipe.

[0010] The installation of branch pipes using this type of 'non-perforated perforation' has the advantage of not affecting the main pipe and thus not affecting the water supply through the main pipe.

[0011] However, the installation of branch pipes using the conventional ‘perforation without interruption’ has the following problems.

[0012] First, a check valve is absolutely necessary for a non-perforated pipe, and these check valves are limited to gated and ball valves. The reason for limiting the check valves to these types is that the cutter attached to the non-perforated pipe must rotate and penetrate the check valve to form a perforation in the main pipe.

[0013] Therefore, the installation of a branch pipe using the conventional 'non-perforated perforation' can only use gate-type valves with relatively high valve heights or relatively expensive ball-type valves, and butterfly valves with relatively low heights and low prices cannot be used because they have a central axis.

[0014] Additionally, for large pipes exceeding 900 mm, there is a problem in that only gate-type valves can be used due to the thickness and weight of ball-type valves.

[0015] Additionally, depending on the depth at which the main pipe is installed, the height of the gate valve may be too high for the branch pipe to be installed, resulting in a higher level of difficulty and a larger civil engineering area. This extends the construction schedule, resulting in inconvenience to the public.

[0016] To address the above issues, the "non-interruptible blocking method" was developed. This "non-interruptible blocking method" is also known as the fluid blocking method or line-stopping method.

[0017] FIG. 1 is an example diagram showing the installation of a branch pipe using a conventional non-stop water shutoff device. As shown in FIG. 1, the non-stop water shutoff method is a method of arbitrarily blocking a part of a pipeline through which fluid flows, such as a water pipe, a heating pipe, or an oil pipe, by using a non-stop water shutoff device (1) having a blocking head of various shapes and structures, such as a pivot-type blocking head, a folding-type blocking head, and an unfolding plate-type blocking head, which is inserted into a pipe to block fluid, and maintaining the pipeline without affecting the fluid supply status of the pipeline through a bypass.

[0018] This type of water interruption method is a method that allows construction of a branch pipe (L5) to be performed without affecting the water supply through the main pipe (L) through a bypass while interrupting only a portion of the section required for branch pipe construction by using a water interruption device (1) having a blocking head.

[0019] However, since at least two water stop devices (1) must be installed to apply the 'non-interruptible water blocking method', the construction cost increases, and since a significant portion of the main pipe (L) must be exposed, the amount of excavation also increases, and the construction period increases due to these problems. In other words, in sections where the main pipe (L) cannot be sufficiently exposed, such as urban areas or densely populated areas, there is a problem in that the 'non-interruptible water blocking method' cannot be applied when installing branch pipes.

[0020] In addition, although branching can be achieved by performing a single perforation, the perforation method requires three perforations.

[0021] Because of this, the main body (L) itself is subjected to relatively high stress by having many perforations (at least 3 locations).

[0022] In addition, in addition to the branch fitting (3), two fittings (2) for installing the fluid shutoff device (1) must be installed.

[0023] In summary, when installing a branch pipe, the conventional 'non-interrupted water perforation' has the advantage of being able to install the branch pipe without affecting the water supply, but has the problem that the butterfly valve, which is relatively low in height and inexpensive, cannot be applied, and the conventional 'non-interrupted water blocking method' has the problem that the difficulty level and construction cost are relatively high compared to 'non-interrupted water perforation' and that a relatively large amount of excavation is required to expose the main pipe (L), and in particular, in terms of work time, it has the problem that it takes considerably more time than the butterfly valve non-interrupted water branch device and non-interrupted water branching method using the same described below.

[0024]

[0025] [Prior Art Literature]

[0026] [Patent Document]

[0027] (Patent Document 1) Utility Model Registration No. 0204756 (registered on September 18, 2000)

[0028]

[0029] The present invention has been devised to solve the above-mentioned problems of the prior art, and the purpose of the present invention is to provide a butterfly valve non-interruptible branch device and a non-interruptible branch method using the same, which can be relatively inexpensive and greatly reduce the construction period for branch pipe installation compared to the conventional non-interruptible blocking method.

[0030]

[0031] The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0032] The present invention provides a non-return valve device for achieving the above-described purpose, characterized by including: a fitting installed in a main body; a butterfly valve body installed on a flange of the fitting; a disc transfer unit for transferring a butterfly disc to the inside of the butterfly valve body; and a rotary pin insertion unit for inserting a rotary pin for fixing the butterfly disc to the butterfly valve body.

[0033] In addition, it is characterized by further including: a sandwich valve installed in the butterfly valve body; a perforation unit installed in the sandwich valve to perforate a branch hole in the main pipe; and a rotation drive unit for rotating the butterfly disk.

[0034] In addition, the rotary pin is characterized in that an undercut is formed, and the butterfly disk is provided with a fixing bolt that is coupled with the undercut.

[0035] In addition, the perforation unit is characterized by comprising a perforation housing coupled to the sandwich valve and a perforator that perforates a branch hole in the main pipe across the perforation housing.

[0036] In addition, the disk transport unit is characterized by comprising a transport housing coupled to the sandwich valve, and a transporter that transports the butterfly disk so that the hinge hole of the butterfly disk and the rotary pin of the butterfly valve body are aligned.

[0037] In addition, it is characterized in that a pressure relief valve is installed between the fitting and the disk transfer unit or perforation unit.

[0038]

[0039] In the non-interruptible branch method using the non-interruptible branch device of the present invention,

[0040] Ⅰ) Step of installing fittings in the main building;

[0041] Ⅱ) Step of installing the butterfly valve body into the fitting;

[0042] Ⅲ) Step of installing a sandwich valve in a butterfly valve body;

[0043] Ⅳ) Step of drilling a branch hole in the main body;

[0044] Ⅴ) Step of installing a butterfly disc in the butterfly valve body; and

[0045] Ⅵ) It is characterized by including a step of installing a branch pipe in a butterfly valve body.

[0046] In addition, the above step Ⅳ) is characterized by comprising a step of installing a perforation unit in a sandwich valve, a step of installing a pressure valve between the fitting and the perforation unit, a step of perforating a branch hole in the main pipe by the perforation unit, a step of closing the sandwich valve and the pressure valve, and a step of separating the perforation unit.

[0047] In addition, the above step V) is characterized by comprising a step of installing a disc transfer unit in a sandwich valve, a step of installing a dynamic pressure valve between a fitting and a disc transfer unit, a step of opening the sandwich valve after dynamic pressure work of the fitting and the disc transfer unit, a step of lowering a butterfly disc to an assembly position by the disc transfer unit, and a step of inserting a rotary pin into the butterfly disc.

[0048] In addition, after the step V), the method is characterized by further including a step of removing the rotary pin insertion unit and installing a rotary drive unit and a cover.

[0049] In addition, the step Ⅵ) is characterized in that it comprises a step of the disc transport unit rising after the butterfly disc and the disc transport unit are separated, a step of removing the disc transport unit after the dynamic pressure valve is closed, a step of fixing the rotary pin to the butterfly disc, a step of removing the sandwich valve, a step of connecting a branch pipe to the butterfly valve body, and a step of the butterfly disc opening the flow path of the butterfly valve body.

[0050] According to the butterfly valve non-interruptible branch device and non-interruptible branch method using the same according to the present invention, by installing a branch pipe with a butterfly valve installed in the main pipe, the cost is relatively low compared to the conventional non-interruptible blocking method, and the construction period for installing the branch pipe can be greatly reduced.

[0051] In particular, the difficulty of the work is very low and there are relatively fewer spatial constraints as the number of man-hours required for bypassing the conventional non-interruptible blocking method is reduced.

[0052] Figure 1 is an example diagram showing the installation of a branch pipe using a conventional non-stop blocking device.

[0053] Figure 2 is a perspective view showing an exploded view of a butterfly valve branch device according to the present invention.

[0054] Figure 3 is a perspective view illustrating a butterfly valve branch device according to the present invention.

[0055] Fig. 4 is a front view illustrating a butterfly valve branch device according to the present invention.

[0056] Fig. 5 is a side view illustrating a butterfly valve branch device according to the present invention.

[0057] Figure 6 is a cross-sectional view taken along the line 'a-a' of Figure 4.

[0058] Figure 7 is a cross-sectional view taken along the line 'b-b' of Figure 5.

[0059] Fig. 8 is a front view showing a butterfly valve non-perforating branch device equipped with a perforator according to the present invention.

[0060] Figure 9 is a flow chart of a non-interruptible branch method using a butterfly valve non-interruptible branch device according to the present invention.

[0061] FIGS. 10a to 10s are exemplary diagrams illustrating a non-interruptible branch method using a butterfly valve non-interruptible branch device according to the present invention.

[0062] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. The advantages and features of the present invention, and methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification.

[0063] Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used in their common sense to those of ordinary skill in the art to which the present invention pertains. Furthermore, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0064] Additionally, the singular in this specification may also include the plural unless specifically stated otherwise in the text. As used herein, the terms "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components, steps, operations, and / or elements.

[0065] FIG. 2 is an exploded perspective view of a butterfly valve insulated branch device according to the present invention, FIG. 3 is a perspective view of a butterfly valve insulated branch device according to the present invention, FIG. 4 is a front view of a butterfly valve insulated branch device according to the present invention, FIG. 5 is a side view of a butterfly valve insulated branch device according to the present invention, FIG. 6 is a cross-sectional view taken along the line 'a-a' of FIG. 4, FIG. 7 is a cross-sectional view taken along the line 'b-b' of FIG. 5, and FIG. 8 is a front view of a butterfly valve insulated branch device equipped with a perforator according to the present invention.

[0066] As shown in FIGS. 2 to 8, a butterfly valve non-stop branch device (A) according to the present invention is composed of a fitting (100) installed in a main pipe (P), a butterfly valve body (200) installed in a flange (110) of the fitting (100), a disk transfer unit (400) that transfers a butterfly disk (300) to the inside of the butterfly valve body (200), and a rotary pin insertion unit (600) that inserts a rotary pin (500) that fixes the butterfly disk (300) to the butterfly valve body (200).

[0067] First, the above fitting (100) is formed with a flange (110) protruding upward in a shape that surrounds the main body (P).

[0068] The above fitting (100) can be installed by welding when the main pipe (P) is a steel pipe. In addition, the fitting (100) can be applied to a known split pipe that is divided into two pieces.

[0069] In addition, a flange (210) is formed at the upper and lower portions of the butterfly valve body (200). That is, the lower flange (210) of the butterfly valve body (200) and the flange (110) of the fitting (100) are firmly fixed to each other by mechanical fastening parts such as bolts.

[0070] In addition, the butterfly valve body (200) is provided with a rotary pin insertion portion (220) in a protruding shape, and a rotary pin insertion hole (221) is formed in the rotary pin insertion portion (220). That is, the rotary pin (500) is inserted into the rotary pin insertion hole (221).

[0071] Meanwhile, the butterfly disk (300) is formed as a circular plate and has a pair of hinge holes (310) formed in the center thereof into which a rotating pin (500) is inserted.

[0072] In addition, the rotary pin insertion unit (600) is detachably installed in the rotary pin insertion portion (220). Furthermore, the rotary pin insertion unit (500) is formed by a pneumatic or hydraulic cylinder and applies a force to push the rotary pin (500) toward the hinge hole (310) of the butterfly disk (300).

[0073] That is, the rotary pin (500) is configured to rotate the butterfly disk (300) relative to the butterfly valve body (200) by being inserted into the rotary pin insertion portion (220) and the hinge hole (310) of the butterfly disk (300). Consequently, the combination of the butterfly valve body (200) and the butterfly disk (300) operates in the same manner as a known butterfly valve.

[0074] Accordingly, the rotary pin (400) and butterfly disk (300) are fixed to the butterfly valve body (200) to complete the butterfly valve.

[0075] In particular, if a branch hole is formed in the main pipe (P) which is in a single state, a butterfly valve can be easily installed.

[0076] The non-permanent branch device (A) according to the present invention further includes a sandwich valve (700) installed in the butterfly valve body (200), a perforation unit (800) installed in the sandwich valve (700) to perforate a branch hole in the main pipe (P), and a rotation drive unit (900) that rotates the butterfly disk (300).

[0077] In addition, the sandwich valve (700) is a known sandwich valve that is coupled to the upper flange (210) of the butterfly valve body (200) and opens and closes the flow path of the butterfly valve body (200) by sliding, and a detailed description of the operation and structure is omitted.

[0078] And, the perforation unit (800) is composed of a perforation housing (810) coupled to the sandwich valve (700) and a perforator (820) that perforates a branch hole in the main pipe (P) across the perforation housing (810).

[0079] Meanwhile, a flange (811) is formed in the perforated housing (810), and the flange (811) and the sandwich valve (700) are fastened by a bolt.

[0080] In addition, the above-mentioned rotation drive unit (900) is installed in the above-mentioned rotation pin insertion portion (220) to rotate the rotation pin (500), and a cover (910) is installed in the opposite rotation pin insertion portion (220) where the above-mentioned rotation drive unit (900) is not installed.

[0081] In addition, the disk transport unit (400) is composed of a transport housing (410) that is coupled to the sandwich valve (700), and a transporter (420) that transports the butterfly disk (300) so that the hinge hole (310) of the butterfly disk (300) aligns with the butterfly valve body (200) and the rotary pin (500).

[0082] In addition, two or more fastening holes (421) are formed in the above-mentioned transporter (420), and two or more fastening grooves (320) into which the fastening holes (421) are inserted are formed in the above-mentioned butterfly disk (300).

[0083] Meanwhile, an undercut (510) is formed on the rotary pin (500), and a fixing bolt (330) that is coupled to the undercut (510) is provided on the butterfly disk (300). Accordingly, the rotary pin (500) is firmly fixed to the butterfly disk (300) by the undercut (510) and the fixing bolt (320).

[0084] Additionally, a pressure relief valve (1000) is installed between the fitting (100) and the disk transfer unit (300) or the perforation unit (800).

[0085] This dynamic pressure valve (1000) is intended to maintain the pressure at the front and rear ends of the sandwich valve (700) at the same level to facilitate the opening and closing of the sandwich valve (700). Here, the dynamic pressure valve (1000) is installed in the transfer housing (410) and the perforation housing (810).

[0086] According to the present invention, after installing a fitting (100) in a main pipe (P), a butterfly valve body (200) and a sandwich valve (700) are installed. Thereafter, a branch hole is perforated in the pipe (P) by a perforation unit (800), and a butterfly disc (300) is installed in the butterfly valve body (200) by a disc transport unit (400). Next, the disc transport unit (400) and the sandwich valve (700) are removed, and a branch pipe is installed.

[0087] That is, before installing the butterfly disc (300), the cutter of the perforation unit can perforate the main pipe by passing through the butterfly valve body. That is, since there is no interference between the butterfly disc and the cutter, the butterfly valve can be applied to the present invention.

[0088] As a result, butterfly valves, which are relatively cheaper than gate valves and ball valves, can be applied.

[0089] Accordingly, by installing a branch pipe to the main pipe (P) through a butterfly disk (300), the cost can be relatively low compared to the conventional non-stop water blocking method, and the construction period for installing the branch pipe can be greatly reduced.

[0090] In particular, the difficulty of the work is very low and there are relatively fewer spatial constraints as the number of man-hours required for bypassing the conventional non-interruptible blocking method is reduced.

[0091] In addition, compared to the conventional branch pipe installation method using 'non-perforated perforation', the branch pipe can be installed after applying the butterfly valve without using the gate valve or ball valve itself.

[0092]

[0093] FIG. 9 is a flow chart of a non-interruptible branch method using a butterfly valve non-interruptible branch device according to the present invention, and FIGS. 10a to 10s are exemplary diagrams illustrating a non-interruptible branch method using a butterfly valve non-interruptible branch device according to the present invention.

[0094] As shown in FIGS. 9 to 10s, the non-single branch method using the non-single branch device according to the present invention installs a fitting (100) in the main pipe (P) (S110, FIG. 10a).

[0095] Next, install the butterfly valve body (200) into the fitting (100) (S120, Fig. 10b)

[0096] Then, a sandwich valve (700) is installed in the butterfly valve body (200) (S130, Fig. 10c).

[0097] Next, a branch hole is drilled in the main body (P) (S140, Figs. 10d-10h).

[0098] Specifically, the S140 step is composed of a step of installing a perforation unit (800) in the sandwich valve (700) (Fig. 10d), a step of installing a pressure valve (1000) between the fitting (100) and the perforation unit (800) (Fig. 10e), a step of perforating a branch hole in the main pipe (P) by the perforation unit (800) (Fig. 10f), a step of closing the sandwich valve (700) and the pressure valve (1000) (Fig. 10g), and a step of separating the perforation unit (800) (Fig. 10h).

[0099] Then, a butterfly disk (300) is installed in the butterfly valve body (200) (S150, Figs. 10i to 10k).

[0100] Specifically, the S150 step is composed of a step of installing a disc transport unit (400) in a sandwich valve (700) and simultaneously installing a dynamic pressure valve (100) between the fitting (100) and the disc transport unit (400) (Fig. 10i), a step of opening the sandwich valve (700) after the dynamic pressure operation of the fitting (100) and the disc transport unit (400) to lower the butterfly disc (300) to the assembly position by the disc transport unit (400) (Fig. 10j), and a step of inserting a rotary pin (500) into the butterfly disc (300) by the rotary pin insertion unit (600) (Fig. 10k).

[0101] After the above step S150, a step of removing the rotary pin insertion unit (600) from the rotary pin (500) and installing the rotary drive unit (900) on the rotary pin (500) is further included (Figs. 10l to 10m). At this time, a cover (910) is also installed.

[0102] Finally, a branch pipe (P1) is installed in the butterfly valve body (200) (S160, Figs. 10n to 10t).

[0103] Specifically, the above step S160 is composed of a step of separating the butterfly disk and the disk transfer unit (400) and then raising the disk transfer unit (400), a step of removing the disk transfer unit after closing the dynamic pressure valve (Fig. 10o), a step of fixing the rotary pin (500) to the butterfly disk (300) by a fixing bolt (330) (Fig. 10p), a step of removing the sandwich valve (Fig. 10q), a step of connecting the branch pipe (P1) to the butterfly valve body (200) (Fig. 10r), and a step of opening the flow path of the butterfly valve body (200) by the butterfly disk (300) (Fig. 10s).

[0104]

[0105] While preferred embodiments of the present invention have been described in detail, the technical scope of the present invention is not limited to the aforementioned embodiments and should be interpreted in accordance with the scope of the patent claims. Those skilled in the art should recognize that numerous modifications and variations are possible without departing from the scope of the present invention.

[0106] For example, in the above description, water pipes were used as an example, but this is not particularly limited and can be applied to various types of pipes such as industrial water cooling pipes, gas pipes, and oil pipes.

[0107]

[0108] [Explanation of symbols]

[0109] A - Infinite branch device

[0110] 100 - Fitting 200 - Butterfly Valve Body

[0111] 300 - Butterfly Disc 400 - Disc Transfer Unit

[0112] 500 - Rotating Pin 600 - Rotating Pin Insertion Unit

[0113] 700 - Sandwich Valve 800 - Perforation Unit

[0114] 900 - Rotating drive unit 910 - Cover

[0115] P - Pipe P1 - Branch

Claims

1. In the method of continuous branching using a butterfly valve continuous branching device, Ⅰ) Step of installing fittings in the main building; Ⅱ) Step of installing the butterfly valve body into the fitting; Ⅲ) Step of installing a sandwich valve in a butterfly valve body; Ⅳ) Step of drilling a branch hole in the main body; Ⅴ) Step of installing a butterfly disc in the butterfly valve body; and Ⅵ) Step of installing a branch pipe in the butterfly valve body; A non-uniform branching method characterized by including:

2. In paragraph 1, The above step Ⅳ) is, A method for continuously branching, characterized by comprising the steps of: installing a perforation unit in a sandwich valve; installing a pressure valve between the fitting and the perforation unit; perforating a branch hole in a main pipe by the perforation unit; closing the sandwich valve and the pressure valve; and separating the perforation unit.

3. In paragraph 2, The above step V) is, A non-interruptible branching method characterized by comprising the steps of: installing a disc transfer unit in a sandwich valve; installing a pressure valve between a fitting and the disc transfer unit; opening the sandwich valve after the pressure operation of the fitting and the disc transfer unit; lowering a butterfly disc to an assembly position by the disc transfer unit; and inserting a rotary pin into the butterfly disc.

4. In paragraph 3, A non-interruptible branch method characterized in that, after the above step V), it further includes a step of removing the rotary pin insertion unit and installing the rotary drive unit and cover.

5. In paragraph 4, The above step Ⅵ) is, A non-interruptible branching method characterized in that the butterfly disc and the disc transport unit are separated and then the disc transport unit is elevated, the disc transport unit is removed after the dynamic pressure valve is closed, the rotary pin is fixed to the butterfly disc, the sandwich valve is removed, the branch pipe is connected to the butterfly valve body, and the butterfly disc opens the flow path of the butterfly valve body.

6. Fittings installed in the main building; Butterfly valve body installed on the flange of the above fitting; A disc transfer unit that transfers the butterfly disc to the inside of the butterfly valve body; and A non-return valve device characterized by including a rotary pin insertion unit for inserting a rotary pin that fixes the butterfly disk to the butterfly valve body.

7. In paragraph 6, A sandwich valve installed in the above butterfly valve body; A perforation unit installed in the sandwich valve to perforate a branch hole in the main body; and A non-returning branch device further comprising a rotary drive unit for rotating the butterfly disk.

8. In paragraph 7, A non-returnable branch device characterized in that an undercut is formed on the above rotary pin and a fixing bolt is provided on the above butterfly disk to be coupled with the undercut.

9. In paragraph 8, The above perforation unit, A branch device characterized by comprising a perforated housing coupled to the sandwich valve and a perforator for perforating a branch hole in the main pipe across the perforated housing.

10. In paragraph 9, The above disk transfer unit, A non-return valve comprising a transfer housing coupled to the sandwich valve, and a transfer device that transfers the butterfly disk so as to align the hinge hole of the butterfly disk with the rotary pin of the butterfly valve body.

11. In paragraph 9, A non-return valve characterized in that a pressure relief valve is installed between the above fitting and the disk transfer unit or the perforation unit.

Images