Patent Description:
A turbo machine refers to an apparatus that generates a driving force used to generate electric power by using fluid (e.g., gas) passing through the turbo machine. Therefore, a turbo machine is usually installed and used together with a generator. Examples of a turbo machine include a gas turbine, a steam turbine, a wind power turbine, or the like. The gas turbine is an apparatus that generates combustion gas by mixing compressed air with natural gas and generates a driving force for generation of electric power by using the combustion gas. The steam turbine is an apparatus that heats water to generate steam and generates a driving force for generation of electric power by using the steam. A wind turbine is an apparatus that converts wind power into a driving force for generation of electric power.

The gas turbine includes a compressor, a combustor, and a turbine. The compressor includes a plurality of compressor vanes and a plurality of compressor blades which are alternately provided in a compressor casing. In addition, the compressor is configured to draw external air in through a compressor inlet scroll strut. The drawn in air is compressed by the compressor vanes and the compressor blades while passing through an inner portion of the compressor. The combustor receives the compressed air compressed at the compressor, and mixes the compressed air with fuel. In addition, the combustor ignites fuel mixed with compressed air by using an igniter, thereby generating high-temperature and high-pressure combustion gas. The combustion gas is supplied to the turbine. The turbine includes a plurality of turbine vanes and a plurality of turbine blades which are alternately arranged in a turbine casing. The turbine passes the combustion gas supplied from the combustor through an inner portion of the turbine. The combustion gas passing through the inner portion of the turbine rotates the turbine blades, and the combustion gas that has completely passed through the inner portion of the turbine is discharged from the turbine through a turbine diffuser.

The steam turbine includes an evaporator and a turbine. The evaporator generates steam by heating water supplied from the outside. Similar to the turbine in the gas turbine, the turbine of the steam turbine includes a plurality of turbine vanes and a plurality of turbine blades which are alternately arranged in a steam turbine casing. However, while the gas turbine uses combustion gas to rotate the turbine blades, the turbine of the steam turbine rotates the turbine blades by passing steam through an inner portion of the turbine, the steam being generated from the evaporator.

The turbines of the gas turbine and the steam turbine includes a turbine rotor and a turbine stator. Further, the turbine stator includes a turbine casing, a vane carrier mounted on an inner circumferential surface of the turbine casing, and a plurality of turbine vanes which is mounted on an inner circumferential surface of the vane carrier and disposed along a circumferential direction of the vane carrier. The vane carrier and the plurality of turbine vanes that is coupled to the vane carrier are disposed in a multi-stage structure along an axial direction of the turbine casing. In addition, the turbine casing includes an upper turbine casing and a lower turbine casing. The turbine casing is divided into the upper turbine casing (half) and the lower turbine casing (half) by an imaginary horizontal plane passing through a center of the turbine casing. The vane carrier includes an upper vane carrier and a lower vane carrier that are respectively mounted on the upper turbine casing and the lower turbine casing. The plurality of turbine vanes also includes a plurality of upper turbine vanes mounted on the upper vane carrier, and a plurality of lower turbine vanes mounted on the lower vane carrier.

In a situation in which a vane carrier is required to be repaired or replaced due to, for example, a damage to a corresponding vane carrier at a specific stage, the corresponding vane carrier at the specific stage is required to be disassembled from the turbine casing. A worker may directly access the upper vane carrier when the upper turbine casing is removed. However, for the lower vane carrier, even if the upper vane carrier at the corresponding stage is removed, it is difficult to access the lower vane carrier at the corresponding stage due to the adjacent upper vane carrier at a different stage.

Various apparatus for use in maintenance work have been proposed in prior art, for example the apparatus disclosed in <CIT>, which may be used in disassembling the lower vane carrier from the lower turbine casing.

<CIT> discloses that a lower inner shell, which is mounted in a lower outer shell of a turbine housing, is disassembled by coupling a dummy inner shell to the lower inner shell and rotate the dummy inner shell and the lower inner shell together so that the lower inner shell can be removed.

In <CIT> a dummy vane carrier is coupled to a lower vane carrier using a fastening bolt that is interposed between the vane carrier and the dummy vane carrier, wherein the fastening bolt can be actuated from its head part positioned on the side of the dummy carrier and from its tip part positioned on the side of the vane carrier. The vane carrier and the dummy vane carrier are rotated so that vane carrier is positioned top, and the fastening bolt is actuated from its tip side to be decoupled.

In prior art, in order to disassemble the lower vane carrier from the lower turbine casing, a rolling jig is mounted on a lower vane carrier at a desired stage, the rolling jig and the lower vane carrier are rotated together as a whole, and then the lower vane carrier is pulled toward an upper portion of the lower turbine casing. However, apparatus disclosed in prior art for disassembling and assembling a lower vane carrier requires an excessively high number of components and an additional machining process. In addition, various components of the disassembling and assembling apparatus may fall downward when the rolling jig and the lower vane carrier are rotated as a whole.

Accordingly, the present invention has been made to solve the above problems occurring in the related art, and to provide an apparatus and method for disassembling and assembling a lower vane carrier that does not require a large number of components and additional machining process. The apparatus is capable of preventing falling and separating of components while the lower turbine casing is disassembled.

To this end, the invention provides an apparatus for disassembling and assembling a lower vane carrier in accordance with claim <NUM> and a method in accordance with claim <NUM>.

According to an aspect of the present invention to achieve the above-described objective, there is provided an apparatus for disassembling and assembling a lower vane carrier, the apparatus including: a rolling jig that is configured for being mounted on the lower vane carrier mounted inside a lower turbine casing; a bolt member that passes through a region where the rolling jig and the lower vane carrier are in contact with each other; and a block member mounted adjacent to the bolt member and configured to prevent the bolt member from being separated.

The bolt member includes: a stem portion that is configured to pass through the lower vane carrier and that passes through the rolling jig; and a head portion that is connected to a first end of the stem portion, wherein a diameter of the head portion is larger than a diameter of the stem portion. Further, the block member is disposed at a position close to the head portion of the bolt member.

The head portion may be disposed at a position close to the rolling jig, and the stem portion may pass through a position close to the lower vane carrier from the position close to the rolling jig.

The stem portion may include: a first stem portion having a first end connected to the head portion and having an outer circumferential surface provided with an external thread; and a second stem portion connected to a second end of the first stem portion. Further, the lower vane carrier may be provided with a first internal thread which is formed in a position where the stem portion is inserted thereinto and to which the external thread of the first stem portion is fastened.

The second stem portion may have a diameter smaller than a diameter of the first stem portion.

On the basis of an imaginary axial direction that passes through a center between the lower vane carrier and the rolling jig, the block member includes include: a pair of side surface block portions spaced apart from each other along the axial direction with respect to the head portion; and a connection block portion connecting the pair of side surface block portions to each other.

The pair of side surface block portions may have a vertical length longer than a vertical length of the head portion, and the connection block portion may be spaced apart from the head portion.

The bolt member may further include a protrusion portion connected to a second end of the stem portion and formed in a polygonal column shape, the protrusion portion being configured such that a wrench for rotating the bolt member is mounted on the protrusion portion.

The protrusion portion may have a hollow shape, and may have an inner portion provided with a second internal thread such that an eyebolt for pulling the bolt member toward the lower vane carrier is inserted and fastened into the inner portion of the protrusion portion.

On the basis of the imaginary axial direction that passes through a center between the lower vane carrier and the rolling jig, the lower vane carrier may include: a first carrier member and a second carrier member that are spaced apart from each other along the axial direction; and a carrier body connecting the first carrier member and the second carrier member to each other. Further, the rolling jig may include: a first jig member in contact with the first carrier member; a second jig member which is spaced apart from the first jig member along the axial direction and which is in contact with the second carrier member; and a plurality of jig connection portions which connects the first jig member and the second jig member to each other, wherein each of the plurality of jig connection portions is spaced apart from each other along a circumferential direction of the first jig member.

An insertion groove may be formed on an inner circumferential surface of the lower turbine casing, and the first carrier member may have a diameter larger than a diameter of the carrier body and may be configured to be inserted into the insertion groove. Further, when the rolling jig and the lower vane carrier are rotated together as a whole with respect to the axial direction as a central axis, the first carrier member may be separated from the insertion groove and the first jig member may be inserted into the insertion groove.

The lower vane carrier may further include a carrier flange through which the bolt member passes, wherein the carrier flange is disposed between the first carrier member and the second carrier member, disposed radially outside of the carrier body, and disposed at a position close to the rolling jig. Further, the rolling jig may further include a jig flange on which the block member is mounted, wherein the rolling is disposed between the first jig member and the second jig member, and disposed such that the jig flange is in contact with the carrier flange.

Each of the plurality of jig connection portions may include: a connection body disposed between the first jig member and the second jig member; and a winding protrusion which protrudes along the circumferential direction of the first jig member from the connection body and on which a rope for rotating the rolling jig is wound.

A jig through-hole to which an eyebolt is fastened may be formed in an outer surface of the connection body on the basis of a radial direction of the rolling jig, wherein the rope passes through the eyebolt.

The lower turbine casing may be provided with a protrusion step that protrudes radially inward from an inner circumferential surface of the lower turbine casing, and the second carrier member may have a diameter smaller than a diameter of the first carrier member. Further, the second carrier member may be disposed such that the second carrier member is facing the protrusion step, and the second jig member may have a diameter smaller than a diameter of the first jig member. Further, in a state in which the second carrier member is facing the protrusion step, when the rolling jig and the lower vane carrier are rotated together as a whole with respect to the axial direction as a central axis, the second carrier member may be separated from the protrusion step and the second jig member may face the protrusion step.

The lower turbine casing may be provided with an insertion groove that is formed on an inner circumferential surface of the lower turbine casing, and a protrusion step may protrude from a position that is spaced apart from the insertion groove along the axial direction. Further, the carrier flange may radially protrude outward further than the second carrier member and may be disposed between the insertion groove and the protrusion step, and the jig flange may radially protrude outward further than the second jig member. Further, in a state in which the carrier flange is disposed between the protrusion step and the insertion groove, when the rolling jig and the lower vane carrier are rotated together as a whole with respect to the axial direction as a central axis, the carrier flange may be separated from the lower vane carrier and the jig flange may be disposed between the protrusion step and the insertion groove.

According to another aspect of the present invention, there is provided a method for disassembling a lower vane carrier, the method including: (A) preparing an apparatus for disassembling and assembling the lower vane carrier, the apparatus including a rolling jig that is mounted on the lower vane carrier mounted inside a lower turbine casing, a bolt member that passes through a region where the rolling jig and the lower vane carrier are in contact with each other, and a block member mounted adj acent to the bolt member and configured to prevent the bolt member from being separated; (B) mounting the rolling jig on the lower vane carrier after an upper turbine casing is disassembled from the lower turbine casing and an upper vane carrier and an upper turbine vane mounted on the upper vane carrier are disassembled from the lower vane carrier; (C) passing the bolt member through the region where the rolling jig and the lower vane carrier are in contact with each other; (D) mounting the block member such that the block member is positioned adjacent to the bolt member; (E) positioning the rolling jig on the lower turbine casing by rotating the lower vane carrier and the rolling jig together as a whole with respect to an imaginary axial direction that passes through a center between the lower vane carrier and the rolling jig; and (F) disassembling the lower vane carrier disposed at a position above the rolling jig according to a process of the (E) from the rolling jig.

A process of the (F) may be performed such that the lower vane carrier is disassembled from the rolling jig by pulling the lower vane carrier upward after the external thread of the bolt member is separated from the first internal thread of the lower vane carrier while the bolt member is moved downward by rotating the bolt member.

According to a further aspect of the present invention, there is provided a method for assembling a lower vane carrier, the method including: (A) preparing an apparatus for disassembling and assembling the lower vane carrier, the apparatus including a rolling jig that is mounted on the lower vane carrier mounted inside a lower turbine casing, a bolt member that passes through a region where the rolling jig and the lower vane carrier are in contact with each other, and a block member mounted adj acent to the bolt member and configured to prevent the bolt member from being separated; (B) passing the bolt member through the lower vane carrier while the lower vane carrier is seated on the rolling jig from above the rolling jig simultaneously when the rolling jig is in a state in which the rolling jig is positioned on the lower turbine casing and the bolt member and the block member are mounted on the rolling jig; (C) fastening an external thread of the bolt member to a first internal thread of the lower vane carrier by rotating the bolt member after the bolt member is pulled upward; (D) mounting the lower vane carrier on the lower turbine casing by rotating the lower vane carrier and the rolling jig together as a whole with respect to an imaginary axial direction that passes through a center between the lower vane carrier and the rolling jig so that the rolling jig is separated from the lower turbine casing; and (E) disassembling the rolling jig from the lower vane carrier after the block member and the bolt member are disassembled from the rolling jig and the lower vane carrier.

A process of the (C) may be performed such that the external thread of the first stem portion is fastened to the first internal thread of the lower vane carrier by mounting the wrench on an outer circumferential surface of the protrusion portion and rotating the wrench after the bolt member is pulled by pulling the eyebolt upward while the eyebolt is in a state in which the eyebolt is fastened to the second internal thread of the inner portion of the protrusion portion.

According to the apparatus for disassembling and assembling the lower vane carrier and to the method for disassembling and assembling the lower vane carrier using the apparatus of the present invention, since the bolt member passes through a region where the rolling jig and the lower vane carrier are in contact with each other and the block member is mounted adj acent to the bolt member and the block member surrounds the bolt member, a problem that the bolt member falls toward the lower turbine casing when the lower vane carrier is disassembled from the rolling jig after the rolling jig and the lower vane carrier are rotated can be prevented.

In addition, according to the present invention, since the apparatus for disassembling and assembling the lower vane carrier is designed in a structure that includes the rolling jig, the bolt member, and the block member, the number of components can be reduced compared to a conventional apparatus, and the lower vane carrier is also can be disassembled from or assembled to the lower turbine casing without performing an additional machining process.

While the present invention will be described with respect to specific embodiments illustrated in the accompanying drawings, these are only for illustrative purposes, and it will be apparent to those skilled in the art that various changes and other equivalent embodiments may be derived from the specific embodiments. Accordingly, the scope of the present invention should be determined by the appended claims rather than by the examples given.

Hereinafter, the present invention will be described with reference to the accompanying drawings under an assumption that a turbo machine in which an apparatus and a method for disassembling and assembling a lower vane carrier according to the present invention are applied is a gas turbine. However, the turbo machine in which the apparatus and the method for disassembling and assembling the lower vane carrier according to the present invention are not limited to a gas turbine but can be used in any apparatus equipped with a turbine.

Referring to <FIG>, a gas turbine <NUM> includes a compressor <NUM>, a combustor <NUM>, and a turbine <NUM>. On the basis of a flow direction of gas (compressed air or combustion gas), the compressor <NUM> is disposed at an upstream side of the gas turbine <NUM>, and the turbine <NUM> is disposed at a downstream side of the gas turbine <NUM>. In addition, the combustor <NUM> is disposed between the compressor <NUM> and the turbine <NUM>.

The compressor <NUM> accommodates compressor vanes and compressor rotors in a compressor casing, and the turbine <NUM> accommodates turbine vanes <NUM> and <NUM> and turbine rotors <NUM> in a turbine casing <NUM> and <NUM>. The compressor vanes and the compressor rotors are disposed in a multi-stage structure along the flow direction of compressed air. The turbine vanes <NUM> and <NUM> and the turbine rotors <NUM> are also disposed in a multi-stage structure along the flow direction of compressed gas. Here, the compressor <NUM> is designed such that an internal space thereof is gradually decreased from a front stage to a rear stage so that air taken into the compressor <NUM> can be compressed. In contrast, the turbine <NUM> is designed such that an internal space thereof is gradually increased from a front stage to a rear stage so that combustion gas supplied from the combustor <NUM> can be expanded.

Meanwhile, a torque tube <NUM> functioning as a torque transmission member for transmitting rotational torque generated from the turbine <NUM> to the compressor <NUM> is disposed between the compressor rotor that is positioned at the rearmost stage of the compressor <NUM> and the turbine rotor <NUM> that is positioned at the foremost stage of the turbine <NUM>. As illustrated in <FIG>, the torque tube <NUM> may be configured of a plurality of torque tube disks arranged in a three-stage structure, but this is only one of various examples. Further, the torque tube <NUM> may be configured of a plurality of torque tube disks arranged in four or more stages or in two or fewer stages.

Each compressor rotor includes a compressor disk <NUM> and compressor blades. In the compressor casing, a plurality (e.g., fourteen) of compressor disks <NUM> are provided, and each of the compressor disks <NUM> is coupled by a tie rod <NUM> such that the compressor disks <NUM> are not spaced apart from each other in an axial direction. In more detail, with the tie rod <NUM> passing through each central portion of the compressor disks <NUM>, each of the compressor disks <NUM> is arranged along the axial direction. In addition, the compressor disks <NUM> adjacent to each other are disposed such that facing surfaces of adjacent compressor disks <NUM> are pressed by the tie rod <NUM> so that the adjacent compressor disks <NUM> cannot rotate relative to each other.

A plurality of compressor blades is radially coupled to an outer circumferential surface of each of the compressor disks <NUM>. In addition, a plurality of compressor vanes is disposed between the compressor blades, wherein the plurality of compressor vanes is mounted on an inner circumferential surface of the compressor casing and formed in an annular shape on the basis of respective stages. Unlike the compressor disks <NUM> configured to rotate about their axis of rotation, the plurality of compressor vanes is configured to be stationary and does not rotate. Further, the compressor vanes is configured to align a flow of compressed air passed through the compressor blades positioned at the upstream side and to guide the compressed air to the compressor blades positioned at the downstream side. Here, the compressor casing and the compressor vanes are collectively referred to as a compressor stator in order to distinguish the compressor casing and the compressor vanes from the compressor rotors.

The tie rod <NUM> is disposed to pass through central portions of the plurality of compressor disks <NUM> and turbine disks that will be described later. Further, a first end portion of the tie rod <NUM> is fastened to an inner portion of the compressor disk <NUM> that is positioned at the foremost side of the compressor <NUM>, and a second end portion of the tie rod <NUM> is fastened by a fixing nut.

A shape of the tie rod <NUM> is not limited to the shape illustrated in <FIG>, and the tie rod <NUM> may be formed in various shapes depending on the needs in the a gas turbine. That is, one shape in which a tie rod is passing through the central portions of the compressor disks <NUM>, another shape in which a plurality of tie rods is arranged in a circumferential direction, or a combination of the above two shapes may be used.

Although not illustrated, a deswirler functioning as a guide vane may be mounted in the compressor <NUM> of the gas turbine <NUM> so as to adjust a flow angle of fluid to a designed flow angle, and thereby increases a pressure of the fluid entering an inlet of the combustor <NUM>.

The combustor <NUM> where the compressed air is mixed with fuel ignites the fuel mixture to generate high-temperature and high-pressure combustion gas having high energy, and increases, through an isobaric combustion, the temperature of the combustion gas to a heat-resistant temperature limit at which components of the combustor <NUM> and components of the turbine <NUM> can endure.

The combustor <NUM> configuring a combustion system of the gas turbine <NUM> may include a plurality of combustors arranged in a combustor casing formed in a cell shape. Each of the combustors includes a nozzle for ejecting fuel, a liner forming a combustion chamber, and a transition piece serving as a connection portion between the combustor <NUM> and the turbine <NUM>.

In detail, the liner provides a combustion space in which fuel ejected from the nozzle is mixed with compressed air supplied from the compressor <NUM> and then combusted. In the liner, the combustion chamber providing the combustion space in which the fuel mixed with air is combusted and a liner annular channel forming an annular space surrounding the combustion chamber are formed. In addition, the nozzle for ejecting fuel is coupled to a front end of the liner, and an igniter is coupled to a side wall of the liner.

Compressed air introduced through a plurality of holes formed in an outer wall of the liner flows in the liner annular channel. Further, compressed air used to cool the transition piece that will be described below also flows through liner channel. As such, since compressed air flows along the outer wall of the liner, the liner may be prevented from being damaged by heat generated by combustion of fuel in the combustion chamber.

The transition piece is connected to a rear end of the liner so as to transfer combustion gas combusted by an ignition plug toward the turbine <NUM>. In the same manner as the liner, the transition piece includes a transition piece annular channel surrounding an internal space of the transition piece. Further, an outer wall of the transition piece is cooled by compressed air flowing along the transition piece annular channel so that the transition piece may be prevented from being damaged by high-temperature combustion gas.

High-temperature and high-pressure combustion gas discharged from the combustor <NUM> is supplied into the turbine <NUM>. The high-temperature and high-pressure combustion gas supplied into the turbine <NUM> expands while passing through an inner portion of the turbine <NUM>, thereby applying impulsive and reaction force to turbine blades to generate a rotational torque. The rotational torque is transmitted to the compressor <NUM> via the torque tube <NUM>. Additional rotational torque in excess of the torque required to drive the compressor <NUM> is used to drive a generator or the like.

The turbine <NUM> basically has a structure similar to that of the compressor <NUM>. The turbine <NUM> includes the plurality of turbine rotors <NUM>. Each turbine rotor <NUM> also includes a turbine disk, and a plurality of turbine blades radially disposed on the turbine disk. The plurality of turbine vanes <NUM> and <NUM> are provided between the turbine blades, wherein the plurality of turbine vanes <NUM> and <NUM> is mounted on an inner circumferential surface of the turbine casing <NUM> and <NUM> and formed in an annular shape on the basis of respective stages. Further, the turbine vanes <NUM> and <NUM> guide the flow direction of combustion gas passing through the turbine blades. Here, the turbine casing <NUM> and <NUM> and the turbine vanes <NUM> and <NUM> are collectively referred to as a turbine stator <NUM> in order to distinguish the turbine casing <NUM> and <NUM> and the turbine vanes <NUM> and <NUM> from the turbine rotors <NUM>.

The turbine stator <NUM> may include the turbine casing <NUM> and <NUM>, a vane carrier <NUM> and <NUM> mounted on an inner circumferential surface of the turbine casing <NUM> and <NUM>, and the plurality of turbine vanes <NUM> and <NUM> mounted on an inner circumferential surface of the vane carrier <NUM> and <NUM> and disposed along a circumferential direction of the vane carrier <NUM> and <NUM>. The vane carrier <NUM> and <NUM> and the plurality of turbine vanes <NUM> and <NUM> coupled to the vane carrier <NUM> and <NUM> are disposed in a multi-stage structure along an axial direction of the turbine casing <NUM> and <NUM>. In addition, the turbine casing <NUM> and <NUM> includes an upper turbine casing <NUM> and a lower turbine casing <NUM>. The turbine casing <NUM> and <NUM> is divided into the upper turbine casing <NUM> and a lower turbine casing <NUM> by an imaginary horizontal plane passing through a center of the turbine casing <NUM> and <NUM>. The vane carrier <NUM> and <NUM> includes an upper vane carrier <NUM> and a lower vane carrier <NUM> that are respectively mounted on the upper turbine casing <NUM> and the lower turbine casing <NUM>. The plurality of turbine vanes <NUM> and <NUM> includes a plurality of upper turbine vanes <NUM> mounted on the upper vane carrier <NUM>, and a plurality of lower turbine vanes <NUM> mounted on the lower vane carrier <NUM>.

Referring to <FIG>, an apparatus (<NUM>; hereinafter, referred to as a 'disassembling and assembling apparatus') for disassembling and assembling a lower vane carrier according to the present invention includes a rolling jig <NUM>, a bolt member <NUM>, and a block member <NUM>. The rolling jig <NUM> is mounted on the lower vane carrier <NUM>. The bolt member <NUM> passes through a portion where the rolling jig <NUM> and the lower vane carrier <NUM> are in contact with each other. The block member <NUM> is mounted adjacent to the bolt member <NUM>, and prevents the bolt member <NUM> from being separated.

An axial direction described hereafter is defined as a direction that passes through a center of the gas turbine <NUM>. The axial direction passes through a center of the vane carrier <NUM> and the rolling jig <NUM> when the vane carrier <NUM> and the rolling jig <NUM> are connected as shown in <FIG>, and is also a longitudinal direction of the tie rod <NUM>. A flow direction of combustion gas that flows inside the turbine <NUM> may be referred to as a part of the axial direction. Hereinafter, the upstream side on the basis of the flow direction of combustion gas is defined as a front direction, and the downstream side on the basis of the flow direction of combustion gas is defined as a rear direction. Meanwhile, a circumferential direction and a radial direction may be defined as a circumferential direction and a radial direction of the turbine casing <NUM> and <NUM>, the vane carrier <NUM> and <NUM>,<NUM> or the rolling jig <NUM>.

Referring to <FIG>, an insertion groove <NUM> and a protrusion step <NUM> are formed on an inner circumferential surface of the lower turbine casing <NUM>. The insertion groove <NUM> is formed in an annular shape that extends along the circumferential direction. The protrusion step <NUM> protrudes radially inward from the inner circumferential surface of the lower turbine casing <NUM> at a position spaced apart from the insertion groove <NUM> in the front direction.

Referring to <FIG>, the lower vane carrier <NUM> includes a first carrier member <NUM>, a second carrier member <NUM>, a carrier body <NUM>, and a carrier flange <NUM>. The first carrier member <NUM> is formed in a semicircular ring shape. The second carrier member <NUM> is formed in a semicircular ring shape. Further, the second carrier member <NUM> is spaced apart from the first carrier member <NUM> in the front direction, and is formed such that a diameter (more particularly, an outer diameter) of the second carrier member <NUM> is smaller than a diameter of the first carrier member <NUM>. The carrier body <NUM> is formed in a semicircular ring shape, and connects the first carrier member <NUM> and the second carrier member <NUM> to each other. The carrier flange <NUM> is disposed between the first carrier member <NUM> and the second carrier member <NUM>. Further, the carrier flange <NUM> is disposed radially outside of the carrier body <NUM> at a position close to the rolling jig <NUM>. The bolt member <NUM> passes through the carrier flange <NUM>.

Referring to <FIG>, the rolling jig <NUM> includes a first jig member <NUM>, a second jig member <NUM>, a jig connection portion <NUM>, and a jig flange <NUM>. The first jig member <NUM> is formed in a semicircular ring shape, and is in contact with the first carrier member <NUM>. The second jig member <NUM> is formed in a semicircular ring shape. Further, the second jig member <NUM> is spaced apart from the first jig member <NUM> in the front direction, and is in contact with the second carrier member <NUM>. The second jig member <NUM> is formed such that a diameter (more particularly, an outer diameter) of the second jig member <NUM> is smaller than a diameter of the first jig member <NUM>. The jig connection portion <NUM> positioned between the first jig member <NUM> and the second jig member <NUM> connects the first jig member <NUM> and the second jig member <NUM> to each other. A plurality of jig connection portions are spaced apart from each other along the circumferential direction. The jig flange <NUM> is disposed between the first jig member <NUM> and the second jig member <NUM>. Further, the jig flange <NUM> is disposed at a position close to the lower vane carrier <NUM>, and is disposed to be in contact with the carrier flange <NUM>. The jig flange <NUM> radially protrudes outward further than the second jig member <NUM>. The block member <NUM> is mounted on the jig flange <NUM>.

Referring to <FIG>, each of the jig connection portions <NUM> includes a connection body <NUM> and a winding protrusion <NUM>. The connection body <NUM> is disposed between the first jig member <NUM> and the second jig member <NUM>, is arranged along the axial direction, and connects the first jig member <NUM> and the second jig member <NUM> to each other. The winding protrusion <NUM> protrudes along the circumferential direction from the connection body <NUM>. Jig through-holes <NUM> may be formed in a radially outer surface of the connection body <NUM>. Eyebolts (not illustrated) may be fastened to the jig through-holes <NUM>. In a state in which the disassembling and assembling apparatus <NUM> is fully mounted on the lower vane carrier <NUM>, the eyebolts are inserted into the jig through-holes <NUM>, and the rope that has passed through the eyebolts is wound on the winding protrusion <NUM>. Then, the lower vane carrier <NUM> and the rolling jig <NUM> can be rotated together as a whole, for example <NUM> degrees, with respect to the axial direction as a central axis by pulling the rope along the circumferential direction by external force.

Referring to <FIG> and <FIG>, the bolt member <NUM> includes a stem portion <NUM>, a head portion <NUM>, and a protrusion portion <NUM>. The stem portion <NUM> passes through the lower vane carrier <NUM> and the rolling jig <NUM>. The head portion <NUM> is connected to a first end of the stem portion <NUM>, and is formed such that a diameter of the head portion <NUM> is larger than a diameter of the stem portion <NUM>. The protrusion portion <NUM> is connected to a second end of the stem portion <NUM>, and is formed in a polygonal column shape. Further, a wrench (not illustrated) for rotating the bolt member <NUM> is mounted on the protrusion portion <NUM>.

Referring to <FIG>, the head portion <NUM> is disposed on a position close to the rolling jig <NUM>, and the stem portion <NUM> passes from the position close to the rolling jig <NUM> to a position close to the lower vane carrier <NUM>. In addition, the block member <NUM> is disposed on a position close to the head portion <NUM> of the bolt member <NUM>. The stem portion <NUM> includes a first stem portion <NUM> and a second stem portion <NUM>. The head portion <NUM> is connected to a first end of the first stem portion <NUM>, and an external thread <NUM> is formed on an outer circumferential surface of the first stem portion <NUM>. The second stem portion <NUM> is connected to a second end of the first stem portion <NUM>. A through-hole (not illustrated) into which the stem portion <NUM> is inserted is formed in the carrier flange <NUM>, and a first internal thread (not illustrated) used to be fastened with the external thread <NUM> of the first stem portion <NUM> is formed on an inner wall of the through-hole. The second stem portion <NUM> is formed such that a diameter of the second stem portion <NUM> is smaller than a diameter of the first stem portion <NUM>. When the stem portion <NUM> is inserted into the through-hole of the carrier flange <NUM>, the first stem portion <NUM> is inserted into the through-hole after the second stem portion <NUM> is inserted into the through-hole. In order for the second stem portion <NUM> not to be fastened to and not to be caught by the first internal thread of the through-hole, the second stem portion <NUM> is formed such that the diameter of the second stem portion <NUM> is smaller than the diameter of the first stem portion <NUM>. After the stem portion <NUM> is completely inserted into the carrier flange <NUM>, the head portion <NUM> is seated on the jig flange <NUM>.

Referring to <FIG>, the protrusion portion <NUM> is formed in a hollow shape, and a second internal thread <NUM> is formed on an inner portion of the protrusion portion <NUM> so that the eyebolt (not illustrated) for pulling the bolt member <NUM> toward the lower vane carrier <NUM> is inserted into and fastened to the protrusion portion <NUM>. After the disassembling and assembling apparatus <NUM> is completely mounted on the lower vane carrier <NUM> as illustrated in <FIG> and <FIG> and the rolling jig <NUM> and the lower vane carrier <NUM> are rotated together as a whole as illustrated in <FIG>, the lower vane carrier <NUM> is pulled upward to disassemble the lower vane carrier <NUM> from the rolling jig <NUM>. Thereafter, when a worker wants to assemble the lower vane carrier <NUM> to the rolling jig <NUM>, a process in which the stem portion <NUM> passes through the carrier flange <NUM> while the lower vane carrier <NUM> is seated on the rolling jig <NUM> is performed. Specifically, after the worker mounts the eyebolt on the second internal thread <NUM> of the protrusion portion <NUM> and pulls the bolt member <NUM> upward, the worker disassembles the eyebolt from the protrusion portion <NUM>, and rotates the protrusion portion <NUM> by using the wrench fastened to an outer circumferential surface of the protrusion portion <NUM>. In this situation, the bolt member <NUM> is rotated, and the external thread <NUM> of the first stem portion <NUM> is fastened to the first internal thread of the carrier flange <NUM>. Thereafter, the lower vane carrier <NUM> and the rolling jig <NUM> are rotated so that the lower vane carrier <NUM> is mounted on the lower turbine casing <NUM> and the rolling jig <NUM> is positioned on an upper portion of the lower turbine casing <NUM>.

Referring to <FIG> and <FIG>, the block member <NUM> includes a pair of side surface block portions <NUM> and a connection block portion <NUM>. The pair of side surface block portions <NUM> is spaced apart from each other along the axial direction with respect to the head portion <NUM>. Between the pair of side surface block portions <NUM>, the connection block portion <NUM> connects the pair of side surface block portions <NUM> to each other. The pair of side surface block portions <NUM> is formed such that a vertical length of the pair of side surface block portions <NUM> is longer than a vertical length of the head portion <NUM>. In addition, the connection block portion <NUM> is spaced apart from the head portion <NUM>.

After the worker mounts the rolling jig <NUM> on the lower vane carrier <NUM> as illustrated in <FIG> and rotates the rolling jig <NUM> and the lower vane carrier <NUM> as illustrated in <FIG>, when the worker wants to pull the lower vane carrier <NUM> upward from the rolling jig <NUM>, the worker loosens the bolt member <NUM> as illustrated in <FIG> such that the bolt member is disassembled from the carrier flange <NUM>. At this time, since the bolt member <NUM> is seated on the block member <NUM> and maintains a state of being caught on the block member <NUM>, the bolt member <NUM> does not fall downward.

Meanwhile, the diameter (more particularly, the outer diameter) of the first carrier member <NUM> is larger than the diameter of the carrier body <NUM>, and the first carrier member <NUM> is inserted into the insertion groove <NUM>. In addition, in a state in which the first carrier member <NUM> is inserted into the insertion groove <NUM>, when the rolling jig <NUM> and the lower vane carrier <NUM> are rotated together as a whole with respect to the axial direction as the central axis, the first carrier member <NUM> is separated from the insertion groove <NUM> and the first jig member <NUM> is inserted into the insertion groove <NUM>.

The second carrier member <NUM> is disposed such that the second carrier member <NUM> is facing the protrusion step <NUM>. In addition, in a state in which the second carrier member <NUM> is facing the protrusion step <NUM>, when the rolling jig <NUM> and the lower vane carrier <NUM> are rotated together as a whole with respect to the axial direction as the central axis, the second carrier member <NUM> is separated from the protrusion step <NUM> and the second jig member <NUM> is facing the protrusion step <NUM>.

The carrier flange <NUM> radially protrudes outward further than the second carrier member <NUM>, and may be disposed between the insertion groove <NUM> and the protrusion step <NUM>. However, when the rolling jig <NUM> and the lower vane carrier <NUM> are rotated together as a whole with respect to the axial direction as the central axis, the carrier flange <NUM> is separated from the lower vane carrier <NUM> and the jig flange <NUM> is disposed between the insertion groove <NUM> and the protrusion step <NUM>.

Hereinafter, a process of disassembling the lower vane carrier <NUM> from the lower turbine casing <NUM> by using the disassembling and assembling apparatus <NUM>, and a process of assembling the lower vane carrier <NUM> to the lower turbine casing <NUM> again after the disassembling process is performed will be described.

Firstly, the process of disassembling the lower vane carrier <NUM> from the lower turbine casing <NUM> by using the disassembling and assembling apparatus <NUM> will be described.

The worker prepares the disassembling and assembling apparatus <NUM> as described above. Then, the worker disassembles the upper turbine casing <NUM> from the lower turbine casing <NUM>, and mounts the rolling jig <NUM> on the lower vane carrier <NUM> after the worker disassembles the upper vane carrier <NUM> and the upper turbine vane <NUM> mounted on the upper vane carrier <NUM>.

Then, the worker passes the stem portion <NUM> of the bolt member <NUM> through a portion where the rolling jig <NUM> and the lower vane carrier <NUM> are in contact with each other, i.e., the jig flange <NUM> and the carrier flange <NUM>. At this time, the worker fastens the external thread <NUM> of the first stem portion <NUM> to the first internal thread of the carrier flange <NUM> by rotating the bolt member <NUM>.

Thereafter, the worker mounts the block member <NUM> such that the block member <NUM> surrounds the head portion <NUM> of the bolt member <NUM>. Then, the worker rotates the lower vane carrier <NUM> and the rolling jig <NUM> together as a whole in order to place the rolling jig <NUM> on the lower turbine casing <NUM>. In a state in which the eyebolt is mounted on the jig through-hole <NUM> and the rope passed through the jig through-hole <NUM> is wound on the winding protrusion <NUM>, the lower vane carrier <NUM> and the rolling jig <NUM> can be rotated by pulling the rope along the circumferential direction.

Finally, the worker disassembles the lower vane carrier <NUM> disposed on the upper portion of the rolling jig <NUM> from the rolling jig <NUM>. Specifically, after the worker separates the external thread <NUM> of the first stem portion <NUM> from the first internal thread of the carrier flange <NUM> by rotating and moving the bolt member <NUM> downward, the worker disassembles the lower vane carrier <NUM> from the rolling jig <NUM> by pulling the lower vane carrier <NUM> upward.

Next, the process of assembling the lower vane carrier <NUM> to the lower turbine casing <NUM> by using the disassembling and assembling apparatus <NUM> will be described.

By the disassembling process as described above, the rolling jig <NUM> is positioned on the lower turbine casing <NUM>, and bolt member <NUM> and the block member <NUM> are mounted on the rolling jig <NUM>. In addition, the lower vane carrier <NUM> is in a state in which the lower vane carrier <NUM> is separated from the rolling jig <NUM>. In this situation, the worker seats the lower vane carrier <NUM> on the rolling jig <NUM> from above the rolling jig <NUM>, and passes the bolt member <NUM> through the lower vane carrier <NUM> at the same time.

After the worker pulls and rotates the bolt member <NUM> upward, the worker fastens the external thread <NUM> of the first stem portion <NUM> to the first internal thread of the carrier flange <NUM>. Specifically, in a state in which the eyebolt is fastened to the second internal thread <NUM> inside the protrusion portion <NUM>, after the worker pulls the bolt member <NUM> by pulling the eyebolt upward, the worker fastens the external thread <NUM> of the first stem portion <NUM> to the first internal thread of the carrier flange <NUM> by mounting the wrench on the outer circumferential surface of the protrusion portion <NUM> and rotating the wrench.

Then, the worker rotates the lower vane carrier <NUM> and the rolling jig <NUM> together as a whole to place the lower vane carrier <NUM> on the lower turbine casing <NUM>. That is, the worker returns the lower vane carrier <NUM> to an original position of the lower vane carrier <NUM>.

Finally, after the worker disassembles the block member <NUM> and the bolt member <NUM> from the rolling jig <NUM> and the lower vane carrier <NUM>, the worker disassembles the rolling jig <NUM> from the lower vane carrier <NUM>. Thereafter, the worker assembles the upper vane carrier <NUM> and the upper turbine vane <NUM> to the lower vane carrier <NUM>, and assembles the upper turbine casing <NUM> to the upper vane carrier <NUM>, so that a repair work and a maintenance work for the turbine stator <NUM> is completed.

Claim 1:
An apparatus for disassembling and assembling a lower vane carrier (<NUM>) mounted inside a lower turbine casing (<NUM>), the apparatus comprising:
a rolling jig (<NUM>) that is configured for being mounted on the lower vane carrier (<NUM>), wherein, when the rolling jig (<NUM>) is mounted on the lower vane carrier (<NUM>), an axial direction passes through a center between the lower vane carrier (<NUM>) and the rolling jig (<NUM>);
a bolt member (<NUM>) that passes through a region where the rolling jig (<NUM>) and the lower vane carrier (<NUM>) are in contact with each other, the bolt member (<NUM>) comprising a stem portion (<NUM>) that passes through the rolling jig (<NUM>) and that is configured for passing through the lower vane carrier (<NUM>), and a head portion (<NUM>) that is connected to a first end of the stem portion (<NUM>), wherein a diameter of the head portion is larger than a diameter of the stem portion (<NUM>); and
a block member (<NUM>) mounted adjacent to the bolt member (<NUM>) and disposed at a position close to the head portion (<NUM>) of the bolt member (<NUM>), the block member (<NUM>) comprising a pair of side surface block portions (<NUM>) spaced apart from each other along the axial direction with respect to the head portion (<NUM>), and a connection block portion (<NUM>) connecting the pair of side surface block portions (<NUM>) to each other, so that the block member (<NUM>) is configured to prevent the bolt member (<NUM>) from being separated.