WO2012099409A2

WO2012099409A2 - Nozzle-boss for high pressure vessel

Info

Publication number: WO2012099409A2
Application number: PCT/KR2012/000470
Authority: WO
Inventors: Sung Chul Kim; Chong Su Seo; Kye Hyoung YU
Original assignee: Iljin Composites
Priority date: 2011-01-19
Filing date: 2012-01-19
Publication date: 2012-07-26
Also published as: WO2012099409A3; KR20120084172A; KR101221004B1

Abstract

A nozzle boss for a high pressure vessel that may improve tightness and a combination force by mounting a plurality of sealing plates each having through holes formed therein. To this end, a nozzle boss for a high pressure vessel including an outer shell and a non-metal internal liner formed inside the outer shell, the nozzle boss including: a boss including a pressurizing portion and protruding from an opening of the internal liner towards an outside; a annular flange extending from a central axis of the boss to a radius-increasing direction along one outer circumferential surface of the boss formed on an inside of the outer shell and including one or more sealing attachment grooves and one or more connection grooves formed in a bottom surface of the annular flange; a plate mounting portion disposed in a downward direction of the annular flange and protruding from the inside of the outer shell; a sealing plate mounted on the plate mounting portion, having a plate shape that extends from the central axis of the boss to the radius-increasing direction of the boss and including one or more sealing attachment grooves, one or more connection holes and one or more through holes that perforate top and bottom surfaces of the sealing plate thus being combined with the annular flange via the connection holes and being combined with the internal liner that is depressed into the through holes; and connection pins for combining the sealing plate with the annular flange via the one or more connection grooves and the one or more connection holes.

Description

NOZZLE-BOSS FOR HIGH PRESSURE VESSEL

The present invention relates to a nozzle boss for a high pressure vessel, and more particularly, to a nozzle boss for a high pressure vessel having a combination structure in which a combination force and tightness between a non-metal liner and a metal boss may be improved.

General pressure vessels are manufactured of metal so as to store high pressure gas. However, these metal pressure vessels are heavy-weight, easily get corroded and have high manufacturing cost.

To solve the problems, a plastic liner is manufactured using a synthetic resin with light weight and an anticorrosive property. The plastic liner is evaluated as material having an excellent property that the strength of the plastic liner is not decreased due to fatigue even in a repetitive charging operation.

A nozzle boss that is combined with the plastic liner formed of a synthetic resin has to be formed of metal. However, gas may leak from a gap between the nozzle boss and the plastic liner during the junction between the nozzle boss formed of metal and the plastic liner formed of a synthetic resin.

Thus, a nozzle boss having a combination structure in which a combination force and tightness between the plastic liner and the nozzle boss are improved, needs to be researched.

FIG. 1 is a combined perspective view of a nozzle boss for a high pressure vessel according to an embodiment of the present invention;

FIG. 2 is an exploded perspective view of the nozzle boss for a high pressure vessel illustrated in FIG. 1;

FIG. 3 is a cross-sectional view from a direction A-A of FIG. 1;

FIG. 4 is a partial cross-sectional view of the nozzle boss for a high pressure vessel illustrated in FIG. 3, which is combined with an internal liner;

FIG. 5 is a plan view of a nozzle boss for a high pressure vessel according to another embodiment of the present invention;

FIG. 6 is a cross-sectional perspective view from a direction B-B of FIG. 5;

FIG. 7 is a plan view illustrating a first modified example of the nozzle boss for a high pressure vessel illustrated in FIG. 5;

FIG. 8 is a plan view illustrating a second modified example of the nozzle boss for a high pressure vessel illustrated in FIG. 5;

FIG. 9 is a longitudinal cross-sectional view of a nozzle boss for a high pressure vessel according to another embodiment of the present invention;

FIG. 10 is a longitudinal cross-sectional view of the nozzle boss for a high pressure vessel illustrated in FIG. 9, which is combined with an internal liner; and

FIG. 11 is a longitudinal cross-sectional view illustrating a modified example of the nozzle boss for a high pressure vessel illustrated in FIG. 9.

FIG. 1 is a combined perspective view of a nozzle boss for a high pressure vessel according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the nozzle boss for a high pressure vessel illustrated in FIG. 1, and FIG. 3 is a cross-sectional view from a direction A-A of FIG. 1. Referring to FIGS. 1, 2, and 3, a nozzle boss 10 for a high pressure vessel according to the present embodiment includes a boss 100, a annular flange 110, a plate mounting portion 120, a plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e, and connection pins 140.

Referring to FIG. 1, the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e are mounted on the plate mounting portion 120 so as to improve a combination force between the boss 100 formed of a metal and an internal liner 12 (see FIG. 4) formed of non-metal and to retain high pressure gas tightness. The plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e each includes one or more through holes 138 formed therein to allow a resin to easily enter the through holes 138 when the internal liner 12 is injection molded using the resin, and the resin that is depressed into the through holes 138 and is hardened serves as a wedge so that the internal liner 12 may be fixed on the plurality of

plates

130a, 130b, 130c, 130d, and 130e.

The boss 100 includes a pressurizing portion (not shown) and protrudes from an opening of the internal liner 12 towards the outside. The boss 100 is an entrance of high pressure gas and may be manufactured by metal casting, forging, and processing. The boss 100 has a cylindrical shape, and an outer surface of the boss 100 may be tapered in a direction of the annular flange 110.

The annular flange 110 extends from a central axis (longitudinal axis) of the boss 100 to a radius-increasing direction of the boss 100 along one outer circumferential surface of the boss 100. One or more sealing attachment grooves 112 and one or more connection grooves 114 are formed in a bottom surface of the annular flange 110. The annular flange 110 may have a predetermined width at which the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e mounted in a downward direction of the annular flange 110 may be supported in an upward direction. The annular flange 110 may be integrated with or separated from the boss 100. When the annular flange 110 is separated from the boss 100, the annular flange 110 may be connected to the boss 100.

In addition, an O-ring (not shown) is attached into the sealing attachment groove 112 and prevents a high pressure fluid inside the high pressure vessel from leaking. One or more connection grooves 114 include female screws through which the connection pins 140 that will be described below may perforate the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e and may be combined with the connection grooves 114.

The plate mounting portion 120 is disposed in the downward direction of the annular flange 110, protrudes from an inside of an outer shell 14, and is inserted in central holes of the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e.

In addition, the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e are mounted on the plate mounting portion 120 and have a plate shape that extends from the central axis (longitudinal axis) of the boss 100 to the radius-increasing direction of the boss 100. The plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e each includes one or more sealing attachment grooves 131, one or

more connection holes

134a, 134b, 134c, 134d, and 134e and one or more through holes 138 that perforate top and bottom surfaces of each of the

sealing plates

130a, 130b, 130c, 130d, and 130e, thus being combined with the annular flange 110 via the

connection holes

134a, 134b, 134c, 134d, and 134e and being wedge-combined with the internal liner 13 that is depressed into the through holes 138.

Here, the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e are mounted in such a way that one or

more connection holes

134a, 134b, 134c, 134d, and 134e are formed in the

sealing plates

130a, 130b, 130c, 130d, and 130e in the same line in a vertical direction. Thus, the

sealing plates

130a, 130b, 130c, 130d, and 130e may be combined with each other. One or more through holes 138 are formed in each of the

sealing plates

130a, 130b, 130c, 130d, and 130e at regular intervals but are dislocated between the

sealing plates

130a, 130b, 130c, 130d, and 130e in the vertical direction.

In order to achieve vertical concordance of the

connection holes

134a, 134b, 134c, 134d, and 134e and vertical non-concordance of the through holes 138, the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e each includes mounting

grooves

135a, 135b, 135c, 135d, and 135e that are formed in one inner circumferential surface of the central hole. The plate mounting portion 120 includes mounting protrusions 122 corresponding to the

mounting grooves

135a, 135b, 135c, 135d, and 135e along a lengthwise direction of the boss 100.

The plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e use the through holes 138 that perforate the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e in the vertical direction to allow a resin to easily enter the through holes 138 so that the boss 100 may be combined with the internal liner 12. To this end, a predetermined gap 142 is formed between the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e. The predetermined gap 142 may be formed by varying a thickness of each of the

sealing plates

130a, 130b, 130c, 130d, and 130e. That is, the

sealing plates

130a, 130b, 130c, 130d, and 130e each includes connection portions 132, which include the

connection holes

134a, 134b, 134c, 134d, and 134e and the sealing attachment grooves 131 and via which the

sealing plates

130a, 130b, 130c, 130d, and 130e are in contact with each other, and perforation portions 136, which include the through holes 138 and via which a gap 142 is between the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e so that the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e are spaced apart from each other by the gap 142.

The connection pins 140 serve to combine the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e with the annular flange 110 via the connection grooves 114 and the

connection holes

134a, 134b, 134c, 134d, and 134e. A plurality of connection pins 140 are disposed, and the connection pins 140 may be formed as male screws along the outer circumferential surface of the boss 100. In this regard, the connection grooves 114 are formed as female screws along the inner circumferential surface of the boss 100 so that the connection pins 140 formed as male screws and the connection grooves 114 formed as female screws may correspond to each other.

FIG. 4 is a partial cross-sectional view of the nozzle boss for a high pressure vessel illustrated in FIG. 3, which is combined with an internal liner. Referring to FIG. 4, the internal liner 12 is injection molded in the form of a vessel by using a resin. In this regard, the resin is depressed into the through holes 138 by the gap 142 formed between the plurality of

sealing plates

130a, 130b, 130c, 130d, and 130e and is hardened so that the internal liner 12 formed of the resin may be combined with the nozzle boss 10. In addition, the outer shell 14 may be formed outside the internal liner 12 by using filament winding of reinforced fiber.

< Second embodiment>

FIG. 5 is a plan view of a nozzle boss for a high pressure vessel according to another embodiment of the present invention, and FIG. 6 is a cross-sectional perspective view from a direction B-B of FIG. 5. Referring to FIGS. 5 and 6, the present embodiment is directed to a nozzle boss 20 for a high pressure vessel, including an outer shell (not shown) formed by filament winding and a non-metal internal liner (not shown) formed inside the external shell. The nozzle boss 20 includes a boss 200 and a annular flange 210. A top surface of the annular flange 210 includes one or more engraving portions 212 and one or more embossing portions 214.

Here, each of the engraving portions 212 is configured so that its engraving width is decreased from a central axis (longitudinal axis) of the boss 200 to a radius-increasing direction of the boss 200, and each of the embossing portions 214 is configured so that its embossing width is increased from the central axis (longitudinal axis) of the boss 200 in the radius-increasing direction of the boss 200. Unlike in the current embodiment, one or more engraving portions 212 and one or more embossing portions 214 may be formed on a bottom surface of the annular flange 210 or on the top and bottom surfaces of the annular flange 210.

In addition, as illustrated in FIGS. 5 and 6, the number of engraving portions 212 and the number of embossing portions 214 are not limited to four, respectively, and may vary according to a width of the boss 200 and a width of the annular flange 210.

The nozzle boss 20 according to the present embodiment is configured so that a resin composition is injection molded onto the engraving portions 212 and the embossing portions 214 and the engraving portions 212 and the embossing portions 214 are closely attached to each other due to the internal liner (not shown). Thus, border walls 216 between the engraving portions 212 and the embossing portions 216 are tightened with the internal liner and thus are combined with and are fixed to the internal liner.

In addition, the border walls 216 may be configured to have a slope from the embossing portions 214 to the engraving portions 212, because a bottom engraving width of the engraving portion 212 is greater than a top engraving width thereof. Thus, the internal liner may be tightened at the hardened engraving portions 212. The slope of the border walls 216 does not need to be uniformly formed, as in the present embodiment, and may be bent in various ways.

Furthermore, in the present embodiment, one or more engraving portions 212 may be connected to each other at one outer circumferential surface of the boss 200, and one or more embossing portions 214 may be connected to each other on annular ends of the annular flange 210, unlike in FIGS. 5 and 6.??

In addition, the annular flange 210 may extend from the central axis of the boss 200 to the radius-increasing direction along one outer circumferential surface of the boss 200 inside the external shell, may be annular form and may be integrated with or separated from the boss 200, as illustrated in FIG. 5. When the annular flange 210 is separated from the boss 200, the annular flange 210 may be connected to the boss 200.

A annular nozzle tightening portion (not shown) may be further disposed at a boundary between the internal liner and the boss 200, may be tightened outside the boss 200 and may be combined with the internal liner and the boss 200 so as to improve tightness of the high pressure vessel. Furthermore, a annular pad portion (not shown) may be further disposed on a bottom surface of the nozzle tightening portion (not shown) so as to improve buffering and tightness efficiency.

FIG. 7 is a plan view illustrating a first modified example of the nozzle boss 20 for a high pressure vessel illustrated in FIG. 5. As illustrated in FIG. 7, in the first modified example of a nozzle boss 21, border walls between the engraving portions 212 and the embossing portions 214 are formed in multi-steps 217. The multi-steps 217 serve as a plurality of step jaws between the engraving portions 212 and the embossing portions 214 may be used to improve tightness inside the high pressure vessel. In this case, the number of multi-steps 217 may be properly selected, and directions of edges of the multi-steps 217 may be selected in various ways.

FIG. 8 is a plan view illustrating a second modified example of the nozzle boss 20 for a high pressure vessel illustrated in FIG. 5. As illustrated in FIG. 8, in the second modified example of a nozzle boss 22, through holes 218 that perforate a pair of border walls 216 are formed in each of one or more embossing portions 214.

When a resin is injection molded to combine an internal liner (not shown) with the engraving portions 212 and the embossing portions 214, the through holes 218 serve to allow the resin to be depressed into the through holes 218, thereby improving a force for combining the internal liner and the nozzle boss 22.

FIG. 9 is a longitudinal cross-sectional view of a nozzle boss for a high pressure vessel according to another embodiment of the present invention, and FIG. 10 is a longitudinal cross-sectional view of the nozzle boss for a high pressure vessel illustrated in FIG. 9, which is combined with an internal liner. Since the present embodiment shows a symmetrical shape in right and left directions, FIGS. 9 and 10 illustrate certain longitudinal cross-sections. As illustrated in FIGS. 9 and 10, the present embodiment is directed to a nozzle boss 30 used for a high pressure vessel, including an outer shell (not shown) formed by filament winding and a non-metal internal liner 32 formed inside the outer shell (not shown). The nozzle boss 30 includes a boss 300, a annular flange 310, a plate mounting portion 320, and a sealing plate 330.

In the present embodiment, the annular flange 310 and the sealing plate 330 mounted on the plate mounting portion 320 form a annular gap corresponding to a vertical length of the plate mounting portion 320, and a liquid resin is injection molded by the annular gap to form an internal liner 32 thus retaining tightness of the high pressure vessel. In particular, in the present embodiment, annular ends of the sealing plate 330 are bent to form a protrusion rim 338 so that the nozzle boss 30 may be caught on the injection-molded internal liner 32 and may be combined therewith.

Hereinafter, the configuration of the present embodiment will be described with reference to FIGS. 9 and 10.

The boss 300 includes a pressurizing portion and protrudes from an opening of the internal liner 32 towards the outside. A annular flange 310 extends from a central axis of the boss 300 to a radius-increasing direction along one outer circumferential surface of the boss 300 formed on an inside of the outer shell (not shown).

The plate mounting portion 320 is disposed in the downward direction of the annular flange 310, protrudes from the inside of the outer shell (not shown), and includes a hole formed around the central axis of the boss 300, wherein one inner circumferential surface of the hole is formed as a female screw 322 so that a male screw 334 of the sealing plate 330 may be combined with the female screw 322.

The sealing plate 330 includes a hollow-shaped combination portion 332 of which one outer circumferential surface is formed as the male screw 334 corresponding to the female screw 322 and which is mounted on the plate mounting portion 320. In addition, the sealing plate 330 further includes a plate portion 336 that extends from the central axis of the boss 300 in the radius-increasing direction along one outer circumferential surface of the hollow-shaped combination portion 332 and has a protrusion rim 338 formed on an end of the plate portion 336.

The plate portion 336 extends wider than the annular flange 310, and the protrusion rim 338 is formed when the end of the plate portion 336 is bent in an upward direction in which the annular flange 310 is disposed, as illustrated in FIG. 9. The protrusion rim 338 is bent thus improving a force for combining the nozzle boss 30 and the internal liner 32 that is injection-molded between the plate portion 336 and the annular flange 310 and increasing tightness. However, the protrusion rim 338 may be formed in a downward direction as well as in the upward direction, and a direction in which the protrusion rim 338 is bent, may be selected in various ways.

In the present embodiment, the nozzle boss 30 may further include a annular nozzle tightening portion 340 that is tightened at a boundary between the internal liner 32 and the boss 300 and is combined with the internal liner 32 and the boss 300 so as to increase tightness. In addition, the nozzle boss 30 according to the present embodiment may further include a annular pad portion 342 disposed on a bottom surface of the nozzle tightening portion 340.

FIG. 11 is a longitudinal cross-sectional view illustrating a modified example of the nozzle boss for a high pressure vessel illustrated in FIG. 9. Since the present embodiment shows a symmetrical shape in right and left directions, FIG. 11 illustrates a certain longitudinal cross-section. Hereinafter, a difference between FIGS. 9, 10, and 11 will be described.

In the modified example of FIG. 11, the annular flange 310 extends wider than the plate portion 336, and a protrusion rim 312 is formed when a annular end of the annular flange 310 is bent in a downward direction in which the plate portion 336 is disposed. Of course, a protrusion rim 339 formed on the annular end of the plate portion 336 is formed when the end of the plate portion 336 is bent in an upward direction in which the annular flange 310 is disposed, as in FIG. 11.

However, in the modified example of FIG.11 the protrusion rims 312 and 339 are formed on the annular flange 310 and the plate portion 336, respectively, to form a annular gap so that a combination force between a nozzle boss 31 and the internal liner 32 and tightness may be further increased.

As described above, according to one or more embodiments of the present invention, a plurality of sealing plates each having through holes formed therein are mounted so that tightness and a combination force may be improved.

In addition, an internal liner is tightened at an engraving portion of a annular flange so that tightness and a combination force may be improved.

Furthermore, a sealing plate that may be combined in a downward direction of the annular flange extending from a boss and has a annular bent portion, as well as the annular flange, is disposed so that tightness may be guaranteed twice and a combination force may be improved.

While this invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. The preferred embodiments should be considered in descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined not by the detailed description of the invention but by the appended claims, and all differences within the scope will be construed as being included in the present invention.

The present invention provides a nozzle boss for a high pressure vessel that may improve tightness and a combination force by mounting a plurality of sealing plates each having through holes formed therein.

The present invention also provides a nozzle boss for a high pressure vessel, wherein an internal liner is tightened at an engraving portion of a annular flange to improve tightness and a combination force.

The present invention also provides a nozzle boss for a high pressure vessel that includes a sealing plate that may be combined in a downward direction of a annular flange extending from a boss and has a annular bent portion, as well as the annular flange, to guarantee tightness twice and to improve a combination force.

Claims

A nozzle boss for a high pressure vessel including an outer shell and a non-metal internal liner formed inside the outer shell, the nozzle boss comprising:

a boss comprising a pressurizing portion and protruding from an opening of the internal liner towards an outside;

a annular flange extending from a central axis of the boss to a radius-increasing direction along one outer circumferential surface of the boss formed on an inside of the outer shell and comprising one or more sealing attachment grooves and one or more connection grooves formed in a bottom surface of the annular flange;

a plate mounting portion disposed in a downward direction of the annular flange and protruding to the inside of the outer shell;

a sealing plate mounted on the plate mounting portion, having a plate shape that extends from the central axis of the boss to the radius-increasing direction of the boss and comprising one or more sealing attachment grooves, one or more connection holes and one or more through holes that perforate top and bottom surfaces of the sealing plate thus being combined with the annular flange via the connection holes and being combined with the internal liner that is depressed into the through holes; and

connection pins for combining the sealing plate with the annular flange via the one or more connection grooves and the one or more connection holes.
The nozzle boss of claim 1, wherein the internal liner is formed by injection molding a resin.
The nozzle boss of claim 1, wherein at least two sealing plates are mounted on the plate mounting portion.
The nozzle boss of claim 3, wherein the one or more through holes are formed in each of the at least two sealing plates at regular intervals but are dislocated between the at least two sealing plates in a vertical direction.
The nozzle boss of claim 3, wherein the one or more connection holes are formed in each of the at least two sealing plates at regular intervals in the same line in the vertical direction.
The nozzle boss of claim 5, wherein the at least two sealing plates and the

plate mounting portion each comprises mounting grooves and mounting protrusions that correspond to each other so as to the one or more connection holes are formed in the same line in the vertical direction.
The nozzle boss of claim 3, wherein the at least two sealing plates each

has a thickness that is decreased from the central axis of the boss to the radius-increasing direction.
The nozzle boss of claim 7, wherein the at least two sealing plates each comprises:

connection portions, which include the one or more connection holes and the one or more sealing attachment grooves and via which the at least two sealing plates are in contact with each other; and

perforation portions, which include the one or more through holes and via which a gap is between the at least two sealing plates so that the at least two sealing plates are spaced apart from each other by the gap.
The nozzle boss of claim 1, wherein the one or more connection grooves

are formed as female screws along an inner circumferential surface of the connection grooves, and the connection pins are formed as male screws along an outer circumferential surface of the connection pins.
A nozzle boss for a high pressure vessel including an outer shell and a non-metal internal liner formed inside the outer shell, the nozzle boss comprising:

a boss comprising a pressurizing portion and protruding from an opening of the internal liner towards an outside; and

a annular flange extending from a central axis of the boss to a radius-increasing direction along one outer circumferential surface of the boss formed on an inside of the outer shell and comprising one or more engraving portions and one or more embossing portions formed on a top surface or a bottom surface of the annular flange so that the one or more engraving portions and the one or more embossing portions are closely attached to each other due to the internal liner,

wherein the one or more engraving portions each has an engraving width that is decreased from the central axis of the boss to the radius-increasing direction, and

the one ore more embossing portions each has an embossing width that is increased from the central axis of the boss to the radius-increasing direction.
The nozzle boss of claim 10, wherein border walls between the one or more engraving portions and the one or more embossing portions are formed in multi-steps.
The nozzle boss of claim 10, wherein the border walls between the one or more engraving portions and the one or more embossing portions each has a slope from the embossing portions to the engraving portions.
The nozzle boss of claim 12, wherein the engraving portions each has a bottom engraving width that is greater than a top engraving width of each engraving portion.
The nozzle boss of claim 10, wherein the one or more engraving portions are connected to each other at one outer circumferential surface of the boss.
The nozzle boss of claim 10, wherein the one or more embossing portions are connected to each other on annular ends of the annular flange.
The nozzle boss of claim 10, wherein the internal liner is formed by injection molding a resin.
The nozzle boss of claim 10, wherein the one or more embossing portions each comprises through holes that perforate a pair of border walls.
The nozzle boss of claim 10, further comprising a annular nozzle tightening portion that is tightened at a boundary between the internal liner and the boss and is combined with the internal liner and the boss.
The nozzle boss of claim 18, further comprising a annular pad portion disposed on a bottom surface of the nozzle tightening portion.
A nozzle boss for a high pressure vessel including an outer shell and a non-metal internal liner formed inside the outer shell, the nozzle boss comprising:

a boss comprising a pressurizing portion and protruding from an opening of the internal liner towards an outside;

a annular flange extending from a central axis of the boss to a radius-increasing direction along one outer circumferential surface of the boss formed on an inside of the outer shell;

a plate mounting portion disposed in a downward direction of the annular flange, protruding to the inside of the outer shell, and comprising a hole formed around the central axis of the boss, wherein one inner circumferential surface of the hole is formed as a female screw; and

a sealing plate comprising a hollow-shaped combination portion of which one outer circumferential surface is formed as a male screw corresponding to the female screw and which is mounted on the plate mounting portion, and a plate portion that extends from the central axis of the boss in the radius-increasing direction along one outer circumferential surface of the hollow-shaped combination portion and has a protrusion rim formed on an end of the plate portion.
The nozzle boss of claim 20, wherein the plate portion extends wider than the annular flange, and the protrusion rim is formed on the end of the plate portion in an upward direction in which the annular flange is disposed.
The nozzle boss of claim 20, wherein the annular flange extends wider than the plate portion, and a protrusion rim is formed on a annular end of the annular flange in a downward or upward direction.
The nozzle boss of claim 22, wherein the protrusion rim of the plate portion is formed on the end of the plate portion in an upward or downward direction.
The nozzle boss of claim 20, further comprising a annular nozzle tightening portion that is tightened at a boundary between the internal liner and the boss and is combined with the internal liner and the boss.
The nozzle boss of claim 24, further comprising a annular pad portion disposed on a bottom surface of the nozzle tightening portion.