The present disclosure relates to a method for estimating a flange surface pressure distribution that estimates a surface pressure distribution on flange surfaces of an upper-half casing and a lower-half casing covering an outer periphery of a rotor in a rotary machine, a method for evaluating leakage of a fluid from between the flange surfaces, and a program and a device for executing these methods.
This application claims priority based on JP 2022-027441 filed in Japan on Feb. 25, 2022, the contents of which are incorporated herein by reference.
A rotary machine such as a steam turbine includes a rotor rotatable around an axis extending in a horizontal direction, a casing covering an outer periphery of the rotor, and a stationary component such as a diaphragm disposed in the casing and attached to the casing. The casing typically includes an upper-half casing on an upper side, a lower-half casing on a lower side, and a plurality of bolts fastening the upper-half casing to the lower-half casing. The upper-half casing includes an upper flange formed with an upper flange surface facing downward. The lower-half casing includes a lower flange formed with a lower flange surface facing upward and opposing the upper flange surface in the vertical direction.
At the time of inspection of the rotary machine, the upper-half casing is removed from the lower-half casing to put the rotary machine into an open state, and a plurality of components constituting the rotary machine are inspected and repaired as necessary. The casing of the rotary machine such as a steam turbine may have inelastic deformation such as creep deformation due to the influence of, for example, heat, during operation. For this reason, the lower-half casing and the upper-half casing in the open state after being operated once are deformed from the factory default in a strict sense. Upon completion of the inspection, the plurality of components are assembled. This assembly step includes a step of fastening the upper-half casing to the lower-half casing by using the plurality of bolts to bring them into a fastened state. In the course of bringing the lower-half casing and the upper-half casing from the open state to the fastened state, the lower-half casing and the upper-half casing are further deformed.
In such a rotary machine, sealing performance between an upper flange and a lower flange is important as described in Non-Patent Document 1 below. In Non-Patent Document 1, as a method for checking sealing performance, first, a paint is applied to one of check targets, and then the upper flange is fastened to the lower flange with bolts. Subsequently, the bolts are removed, and the paint adhesion state of the remaining one of the check targets is checked.
Non-Patent Document 1: “Valqua Technology News, No. 33 Summer 2017,” p. 10, edited and issued by NIPPON VALQUA INDUSTRIES, LTD. on Aug. 31, 2017
In the technique described in Non-Patent Document 1 described above, in order to check the sealing performance between the upper flange and the lower flange, it is necessary to once fasten the upper flange to the lower flange with the bolts and then remove the bolts to return an upper-half casing and a lower-half casing to an open state. Thus, in the technique described in Non-Patent Document 1 described above, there is a problem in that it takes time and effort to check the sealing performance between the upper flange and the lower flange.
In light of the foregoing, an object of the present disclosure is to provide a technique that can reduce time and effort for checking sealing performance between two flanges.
A method for estimating a flange surface pressure distribution in a rotary machine as one aspect for achieving the above-described object is applied to a rotary machine below.
The rotary machine includes: a rotor rotatable around an axis extending in a horizontal direction; a casing in which a working fluid flow and which covers an outer periphery of the rotor; and a stationary component disposed in the casing and attached to the casing. The casing includes an upper-half casing on an upper side, a lower-half casing on a lower side, and a plurality of bolts fastening the upper-half casing to the lower-half casing. The upper-half casing includes an upper flange formed with an upper flange surface facing downward. The lower-half casing includes a lower flange formed with a lower flange surface facing upward and opposing the upper flange surface in the vertical direction. The upper flange and the lower flange include bolt holes penetrating therethrough in the vertical direction, and the respective plurality of bolts can be inserted into the bolt holes.
The method for estimating a flange surface pressure distribution in the above rotary machine described above includes:
In general, when the sealing performance between the upper flange and the lower flange is checked, a paint is first applied to one of check targets, and then the upper flange is fastened to the lower flange with bolts. Subsequently, the bolts are removed, the upper-half casing and the lower-half casing are returned to an open state, and then the paint adhesion state of the remaining one of the check targets is checked. However, in the present aspect, the pressure distribution of one flange surface out of the upper flange surface and the lower flange surface when the casing is changed to the fastened state is estimated. Accordingly, in the present aspect, in order to check the sealing performance between the upper flange and the lower flange, it is not necessary to bring the casing in the open state into the fastened state and then return the casing to the open state again, and thus it is possible to reduce the time and effort for checking the sealing performance.
A program for estimating a flange surface pressure distribution in a rotary machine as one aspect for achieving the above-described object is applied to a rotary machine below.
The rotary machine includes: a rotor rotatable around an axis extending in a horizontal direction; a casing in which a working fluid can flow and which covers an outer periphery of the rotor; and a stationary component disposed in the casing and attached to the casing. The casing includes an upper-half casing on an upper side, a lower-half casing on a lower side, and a plurality of bolts fastening the upper-half casing to the lower-half casing. The upper-half casing includes an upper flange formed with an upper flange surface facing downward. The lower-half casing includes a lower flange formed with a lower flange surface facing upward and opposing the upper flange surface in the vertical direction. The upper flange and the lower flange include bolt holes penetrating therethrough in the vertical direction, and the respective plurality of bolts can be inserted into the bolt holes.
The program for estimating a flange surface pressure distribution in the above rotary machine causes a computer to execute:
By causing the computer to execute the program according to the present aspect, the time and effort for checking the sealing performance between the upper flange surface and the lower flange surface can be reduced as in the method according to the one aspect described above.
A device for estimating a flange surface pressure distribution in a rotary machine as one aspect for achieving the above-described object is applied to a rotary machine below.
The rotary machine includes: a rotor rotatable around an axis extending in a horizontal direction; a casing in which a working fluid can flow and which covers an outer periphery of the rotor; and a stationary component disposed in the casing and attached to the casing. The casing includes an upper-half casing on an upper side, a lower-half casing on a lower side, and a plurality of bolts fastening the upper-half casing to the lower-half casing. The upper-half casing includes an upper flange formed with an upper flange surface facing downward. The lower-half casing includes a lower flange formed with a lower flange surface facing upward and opposing the upper flange surface in the vertical direction. The upper flange and the lower flange include bolt holes penetrating therethrough in the vertical direction, and the respective plurality of bolts can be inserted into the bolt holes.
The device for estimating a flange surface pressure distribution in the above rotary machine includes:
Similar to the method according to the one aspect described above, in the present aspect, the time and effort for checking the sealing performance between the upper flange surface and the lower flange surface can be reduced.
According to one aspect of the present disclosure, a flange surface pressure distribution in a rotary machine can be estimated, and thus the time and effort for checking the sealing performance between the two flanges can be reduced.
Embodiments of a method for estimating a flange surface pressure distribution in a rotary machine, a method for evaluating leakage of a fluid from between flange surfaces, a program for executing these methods, and a device for executing these methods according to the present disclosure will be described below.
A rotary machine in the present embodiment will be described with reference to
As illustrated in
Here, a direction in which the axis Ar extends is referred to as an axial direction Dy, a circumferential direction with respect to the axis Ar is simply referred to as a circumferential direction Dc, and a radial direction with respect to the axis Ar is simply referred to as a radial direction Dr. Further, in the radial direction Dr, a side closer to the axis Ar is referred to as a radial inner side Dri, and a side far from the axis Ar is referred to as a radial outer side Dro. In addition, among the reference signs used in the drawings, U means an upper half and L means a lower half.
The rotor 15 includes a rotor shaft 16 extending in the axial direction Dy, and a plurality of rotor blade rows 17 attached to the rotor shaft 16 along the axial direction Dy. Each of the plurality of rotor blade rows 17 includes a plurality of rotor blades aligned in the circumferential direction Dc with respect to the axis Ar. Both end portions of the rotor shaft 16 protrude from the casing 30 in the axial direction Dy. One end portion of the rotor shaft 16 in the axial direction Dy is rotatably supported by the first shaft bearing device 12a mounted on the frame 11. The other end portion of the rotor shaft 16 in the axial direction Dy is rotatably supported by the second shaft bearing device 12b mounted on the frame 11.
The first shaft sealing device 13a is provided at one end portion of the casing 30 in the axial direction Dy. The second shaft sealing device 13b is provided at the other end portion of the casing 30 in the axial direction Dy. Each of the first shaft sealing device 13a and the second shaft sealing device 13b is a device that seals a gap between the rotor shaft 16 and the casing 30.
The plurality of diaphragms 20 are aligned in the axial direction Dy in the casing 30. Each of the plurality of diaphragms 20 includes a lower-half diaphragm 20L that constitutes a portion below the axis Ar and an upper-half diaphragm 20U that constitutes a portion above the axis Ar. Each of the lower-half diaphragm 20L and the upper-half diaphragm 20U includes a plurality of stator vanes 22 aligned in the circumferential direction Dc, a diaphragm inner ring 23 that connects portions of the plurality of stator vanes 22 on the radial inner side Dri to each other, a diaphragm outer ring 24 that connects portions of the plurality of stator vanes 22 on the radial outer side Dro to each other, and a sealing device 25 mounted on the radial inner side Dri of the diaphragm inner ring 23. The sealing device 25 is a sealing device that seals a gap between the diaphragm inner ring 23 and the rotor shaft 16.
Each of the first shaft sealing device 13a, the second shaft sealing device 13b, and the plurality of diaphragms 20 described above is a stationary component that extends in the circumferential direction with respect to the axis Ar and is attached to the casing 30.
As illustrated in
As illustrated in
The first supported portion 35a protrudes from one side of both sides of the lower flange 32L in the axial direction Dy toward the one side. The second supported portion 35b protrudes from the other side of the both sides of the lower flange 32L in the axial direction Dy toward the other side. Thus, the second supported portion 35a is separated from the first supported portion 35b in the axial direction Dy. In the present embodiment, an upper surface 35ap of the first supported portion 35a and an upper surface 35bp of the second supported portion 35b are surfaces continuous with the lower flange surface 33L.
The lower flange 32L and the upper flange 32U are formed with bolt holes 34 which penetrate therethrough in the vertical direction Dz, and the respective plurality of bolts 39 can be inserted into the bolt holes 34. The lower-half casing 30L and the upper-half casing 30U are fastened by the bolts 39 inserted into the bolt holes 34 of the lower flange 32L and the bolt holes 34 of the upper flange 32U.
An inside surface of the lower-half casing main body 31L and an inside surface of the upper-half casing 30U are formed with stationary component storage portions 36 in which the respective plurality of stationary components described above is stored. Each of the stationary component storage portions 36 of the lower-half casing main body 31L is a groove that is recessed from the inside surface of the lower-half casing main body 31L toward the radial outer side Dro and extends in the circumferential direction Dc. Each of the stationary component storage portions 36 of the upper-half casing main body 31U is a groove that is recessed from the inside surface of the upper-half casing main body 31U toward the radial outer side Dro and extends in the circumferential direction Dc. The diaphragm 20, which is one of the stationary components, is supported by a portion near the flange surface of the stationary component storage portion 36 extending in the circumferential direction Dc.
An inside surface of the casing 30 is exposed to high-temperature steam generated by the operation of the steam turbine 10. Thus, the casing 30 may undergo inelastic deformation such as creep deformation due to the operation of the steam turbine 10. As a result of this deformation, in the open state where the upper-half casing 30U is not fastened to the lower-half casing 30L, the positions of the lower flange surface 33L and the upper flange surface 33U in the vertical direction Dz are shifted according to a location in the axial direction Dy as illustrated in
When the upper-half casing 30U deformed as described above is fastened to the lower-half casing 30L deformed as described above to bring the casing 30 into the fastened state, the positions of the lower flange surface 33L and the upper flange surface 33U in the vertical direction Dz are further shifted according to a location in the axial direction Dy as illustrated in
In the steam turbine 10, the sealing performance between the upper flange surface 33U and the lower flange surface 33L is important for suppressing leakage of steam from between the upper flange surface 33U and the lower flange surface 33L. As described above, the casing is deformed when a state changes from the open state to the fastened state. Thus, even when the shapes of the upper flange surface and the lower flange surface in the open state are known in advance, it is not possible to grasp the sealing performance between the upper flange surface 33U and the lower flange surface 33L directly from these surface shapes.
Therefore, embodiments of a device for estimating a flange surface pressure distribution that estimates the surface distribution on the flange surface in the steam turbine 10 which is a rotary machine, a method for evaluating leakage of a fluid from between flange surfaces, a program for executing these methods, and a device for executing these methods will be described.
A device for estimating a flange surface pressure distribution and a device for evaluating leakage according to the present embodiment will be described with reference to
A device for evaluating leakage 50 according to the present embodiment includes a device for estimating a flange surface pressure distribution 50a. The device for evaluating leakage 50 is a computer. The device for evaluating leakage 50 includes a central processing unit (CPU) 60 that performs various operations, a memory 57 that serves as a working area or the like for the CPU 60, an auxiliary storage device 58 such as a hard disk drive device, a manual input device (input device) 51 such as a keyboard and a mouse, a display device (output device) 52, an input/output interface 53 for the manual input device 51 and the display device 52, a device interface (input device) 54 for transmitting and receiving data to and from a three-dimensional shape measuring device 69 such as a three-dimensional laser measuring device, a communication interface (input/output device) 55 for communicating with the outside via a network N, and a storage and reproduction device (input/output device) 56 that performs data storage processing and data reproduction processing for a disk storage medium D which is a non-transitory storage medium.
The auxiliary storage device 58 stores in advance a program for evaluating leakage 58p. The program for evaluating leakage 58p includes a program for estimating a flange surface pressure distribution 58pa. The program for evaluating leakage 58p is loaded into the auxiliary storage device 58 from the disk storage medium D, which is a non-transitory storage medium, via the storage and reproduction device 56, for example. Note that the program for evaluating leakage 58p may be loaded into the auxiliary storage device 58 from an external device via the communication interface 55.
The CPU 60 functionally includes a reference model receiving unit 61, a measured coordinate receiving unit 63, a condition receiving unit 64, a modified model creating unit 65, a pressure distribution estimating unit 66, and a leakage evaluating unit 67. Each of these functional units 61 and 63 to 67 is enabled by the CPU 60 executing the program for evaluating leakage 58p stored in the auxiliary storage device 58. Among the functional units 61 and 63 to 67 described above, the functional units 61 and 63 to 66 excluding the leakage evaluating unit 67 are enabled by the CPU 60 executing the program for estimating a flange surface pressure distribution 58pa included in the program for evaluating leakage 58p. The device for estimating a flange surface pressure distribution 50a included in the device for evaluating leakage 50 includes the functional units 61 and 63 to 66 excluding the leakage evaluating unit 67 among the functional units 61 and 63 to 67 described above. The operations of the respective functional units 61 and 63 to 67 will be described below.
The method for estimating a flange surface pressure distribution and the method for evaluating leakage of a fluid from between flange surfaces according to the present embodiment will be described in accordance with a flowchart illustrated in
An operator inputs a three-dimensional reference shape model 80 of the steam turbine 10 acquired in advance to the device for evaluating leakage 50. The input method may be any one of input by the manual input device 51, input via the network N from a computer in which the three-dimensional reference shape model 80 is stored, and input via the storage and reproduction device 56 from the disk storage medium D in which the three-dimensional reference shape model 80 is stored. As described above, the reference model receiving unit 61 of the device for evaluating leakage 50 receives the input of the three-dimensional reference shape model 80 from the outside and stores the three-dimensional reference shape model 80 in the auxiliary storage device 58 (reference model receiving step S1).
The three-dimensional reference shape model 80 is a model in which a plurality of components constituting the steam turbine 10 are divided into a plurality of minute elements in the form of a mesh in order to simulate deformation or the like of the plurality of components by a finite element method or the like. The three-dimensional reference shape model 80 may be a model represented by three-dimensional design data created at the time of designing the steam turbine 10, or may be a model represented by three-dimensional data obtained by actual measurement performed, for example, before the shipment of the steam turbine 10 from a factory, or at the time of a previous periodic inspection. That is, the three-dimensional reference shape model 80 only needs to be a model represented by three-dimensional data obtained ahead of operation before a periodic inspection. Three-dimensional coordinate data at respective positions of the plurality of components constituting the steam turbine 10 can be obtained from the three-dimensional reference shape model 80.
The steam turbine 10 is disassembled and reassembled each time an inspection or the like is performed. When the disassembly of the steam turbine 10 is completed, the upper-half casing 30U is removed from the lower-half casing 30L as illustrated in
When the steam turbine 10 is disassembled and the casing 30 is in the open state as described above, the operator measures three-dimensional coordinate values at a plurality of positions 78 on the upper flange surface 33U and three-dimensional coordinate values at a plurality of positions 78 on the lower flange surface 33L by using the three-dimensional shape measuring device 69 such as a three-dimensional laser measuring device as illustrated in
The three-dimensional coordinate data according to the present embodiment includes a coordinate value indicating a position in the axial direction Dy extending in the horizontal direction, a coordinate value indicating a position in the vertical direction Dz perpendicular to the axial direction Dy, and a coordinate value indicating a position in a lateral direction Dx perpendicular to the axial direction Dy in the horizontal direction.
The operator further inputs conditions for evaluating leakage of steam by using the manual input device 51 or the like. The condition receiving unit 64 of the device for evaluating leakage 50 receives the conditions (condition receiving step S4). The conditions include a tightening torque of the plurality of bolts 39, an elastic coefficient of the plurality of bolts 39, elastic coefficients of the upper-half casing 30U and the lower-half casing 30L, weights of the upper-half casing 30U and the lower-half casing 30L, a weight of the stationary component, and the like.
When the measured coordinate receiving unit 63 receives a plurality of pieces of measured three-dimensional coordinate data and the condition receiving unit 64 receives the conditions, the modified model creating unit 65 of the device for evaluating leakage 50 modifies the three-dimensional reference shape model 80 based on the measured three-dimensional coordinate data at the plurality of positions 78 received by the measured coordinate receiving unit 63 to create a three-dimensional modified shape model 80m (see
For example, as illustrated in
Subsequently, as illustrated in
This data extraction processing is performed to exclude, from the measured three-dimensional coordinate data at the plurality of points 85 received in the measured coordinate receiving step S3, measured three-dimensional coordinate data at points on a wall of an edge of the flange surface and points on the inside surfaces of the bolt holes 34 penetrating through the flange surface. Thus, as illustrated in
Next, as illustrated in
The measured three-dimensional coordinate data related to the point 85 obtained by the three-dimensional shape measuring device 69 contains an error. For example, when the three-dimensional shape measuring device 69 is a three-dimensional laser measuring device, the measured three-dimensional coordinate data measured by the three-dimensional laser measuring device will contain an error when there is a minute floating object between a measurement target and the three-dimensional laser measuring device. Thus, in the present embodiment, an error range of the three-dimensional coordinate data related to the point 85 obtained by the three-dimensional shape measuring device 69 is narrowed by setting a point that is the median of the plurality of points 85 included in the three-dimensional block 83 as the representative point 87 in the three-dimensional block 83. Note that when the number of the plurality of points 85 included in the three-dimensional block 83 is extremely small, the representative point 87 is not set for this three-dimensional block 83. This is because when the number of the points 85 is extremely small, even when the representative point 87 is set among the plurality of points 85, the error range of the three-dimensional coordinate data of the representative point 87 is not necessarily narrowed.
The representative point 87 may be determined by robust estimation or bi-weight estimation based on the Lorentz distribution of the plurality of points 85 included in the polygons 86a identified by the plurality of pieces of polygon data extracted in the extraction processing.
The modified model creating unit 65 connects the respective representative points 87 of the plurality of three-dimensional blocks 83 to each other with a plane or a curved surface as a complementary surface to create surface shape data of the complementary surface including the respective representative points 87 of the plurality of three-dimensional blocks 83. The surface shape data is represented by a function F indicating the shape of the entire flange surface.
As illustrated in
When the three-dimensional modified shape model 80m is created, the pressure distribution estimating unit 66 simulates the distribution of pressure applied to one flange surface out of the upper flange surface 33U and the lower flange surface 33L under the conditions received in the condition receiving step S4 by using the three-dimensional modified shape model 80m (pressure distribution estimating step S6). First, for all meshes including surfaces that form the flange surface (hereinafter referred to as mesh flange surfaces) among a plurality of meshes in the three-dimensional modified shape model 80m, the pressure distribution estimating unit 66 obtains pressures applied to the mesh flange surfaces by simulation. Next, the pressure distribution estimating unit 66 sets a region in which mesh flange surfaces within a predetermined pressure range are present as a region to which a pressure within the predetermined pressure range is applied in the flange surface. For example, as illustrated in
The above-described operations in the device for evaluating leakage 50 are operations by the device for estimating a flange surface pressure distribution 50a included in the device for evaluating leakage 50.
When the distribution of the pressure applied to the flange surface is obtained, the leakage evaluating unit 67 of the device for evaluating leakage 50 obtains a high leakage region in which steam is highly likely to leak in the flange surface (leakage evaluating step S7). Here, the leakage evaluating unit 67 obtains a region in which a value obtained by dividing the pressure indicated by the pressure distribution obtained in advance by the maximum pressure or the rated pressure of the steam (working fluid) is less than a predetermined tolerance, and sets this region as the high leakage region. For example, as illustrated in
If the high leakage region 89 is present in the flange surface, the operator sets a tightening torque of the bolt 39 inserted into the bolt hole 34 close to the high leakage region 89 to be high. At this time, if necessary, the operator changes the material of the bolt 39 so that the bolt 39 can withstand the set tightening torque.
As described in the background art section, when the sealing performance between the upper flange 32U and the lower flange 32L is checked, a paint is first applied to one of check targets, and then the upper flange 32U is fastened to the lower flange 32L with bolts 39. Subsequently, the bolts 39 are removed, the upper-half casing 30U and the lower-half casing 30L are returned to the open state, and then the paint adhesion state of the remaining one of the check targets is checked. However, in the present embodiment, the distribution of pressure applied to one flange surface out of the upper flange surface 33U and the lower flange surface 33L when the casing 30 is changed to the fastened state is estimated by simulation. Accordingly, in the present embodiment, in order to check the sealing performance between the upper flange 32U and the lower flange 32L, it is not necessary to bring the casing 30 in the open state into the fastened state and then return the casing 30 to the open state again, and thus it is possible to reduce the time and effort for checking the sealing performance.
Further, in the present embodiment, since the high leakage region 89 is estimated in the flange surface, the sealing performance can be easily checked.
In the present embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 are displayed on the display device 52. However, when the high leakage region 89 is displayed on the display device 52, the distribution of pressure applied to the flange surface need not be displayed on the display device 52.
In the present embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 are estimated. However, the distribution of pressure applied to the flange surface is estimated while the high leakage region 89 need not be estimated.
In the present embodiment, after the reference model receiving step SI, the measured coordinate receiving step S3 is executed, and then the condition receiving step S4 is executed. However, the reference model receiving step SI and the measured coordinate receiving step S3 may be executed in any order as long as these steps are executed before the modified model creating step S5. In addition, the condition receiving step S4 may be executed in any order as long as this step is executed before the pressure distribution estimating step S6.
In the first embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 when the casing 30 is in the fastened state are estimated. On the other hand, in the present embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 when the casing 30 is in the fastened state and the steam turbine 10 is in operation are estimated.
A device for executing the method according to the present embodiment is the same as the device 50 described with reference to
In the condition receiving step S4 in the present embodiment, in addition to the conditions received in the condition receiving step S4 in the first embodiment, the condition receiving unit 64 receives, as conditions, a pressure distribution and a temperature distribution in the casing 30, a temperature outside the casing 30, a thrust force applied to the stationary component, a linear expansion coefficient of the bolt 39 according to temperature, and linear expansion coefficients and heat transfer coefficients of the upper-half casing 30U and the lower-half casing 30L according to temperature when the steam turbine 10 is in operation.
In the pressure distribution estimating step S6 in the present embodiment, the pressure distribution estimating unit 66 simulates the distribution of pressure applied to the flange surface when the casing 30 is in the fastened state and the steam turbine 10 is in operation by using the conditions received in the condition receiving step S4.
Also in the leakage evaluating step S7 in the present embodiment, the leakage evaluating unit 67 obtains the high leakage region 89 in which steam is highly likely to leak in the flange surface.
In the present embodiment, the pressure distribution of the flange surface when the casing 30 is in the fastened state and the steam turbine 10 is in operation is estimated by simulation. Accordingly, in the present embodiment, the sealing performance when the steam turbine 10 is in operation can be checked.
Note that in order to increase the accuracy of simulating the pressure distribution, a heat transfer coefficient between the steam and the casing 30 according to the temperature of the upper-half casing 30U and the lower-half casing 30L may be further received in the condition receiving step S4 according to the present embodiment.
In the first embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 when the casing 30 is in the fastened state are estimated. On the other hand, the present embodiment estimates the distribution of pressure applied to the flange surface and the high leakage region 89 when the casing 30 is in the fastened state and the steam turbine 10 is in operation, and after a flow rate of steam is changed.
A device for executing the method according to the present embodiment is the same as the device 50 described with reference to
Similar to the condition receiving step S4 in the second embodiment, in the condition receiving step S4 in the present embodiment, in addition to the conditions received in the condition receiving step S4 in the first embodiment, the condition receiving unit 64 receives, as conditions, a temperature outside the casing 30, a thrust force applied to the stationary component, a linear expansion coefficient of the bolt 39 according to temperature, and linear expansion coefficients and heat transfer coefficients of the upper-half casing 30U and the lower-half casing 30L according to temperature when the steam turbine 10 is in operation. Further, the condition receiving unit 64 receives, as the conditions, a change time from start to end of a change in the flow rate of the steam flowing into the casing 30, pressure distributions and temperature distributions in the casing 30 before and after the change in the flow rate of the steam, and a thrust force applied to the stationary component before and after the change in the flow rate of the steam when the steam turbine 10 is in operation.
In the pressure distribution estimating step S6 in the present embodiment, the pressure distribution estimating unit 66 simulates, by using the conditions received in the condition receiving step S4, the distribution of pressure applied to the flange surface when the casing 30 is in the fastened state and the steam turbine 10 is in operation, and after the change in the flow rate of the steam.
Also in the leakage evaluating step S7 in the present embodiment, the leakage evaluating unit 67 obtains the high leakage region 89 in which steam is highly likely to leak in the flange surface.
In the present embodiment, the pressure distribution of the flange surface when the casing 30 is in the fastened state and the steam turbine 10 is in operation and after the change in the flow rate of the steam is estimated by simulation. Accordingly, in the present embodiment, the sealing performance when the steam turbine 10 is in operation and after the change in the flow rate of the steam can be checked. Therefore, the present embodiment is effective for checking the sealing performance at the time of startup of the steam turbine 10 and for checking the sealing performance when the flow rate of the steam flowing into the steam turbine 10 rapidly changes.
In the first embodiment, the distribution of pressure applied to the flange surface and the high leakage region 89 when the casing 30 is in the fastened state are estimated. On the other hand, the present embodiment estimates the pressure distribution of the flange surface when the casing 30 is in the fastened state and after creep deformation at a scheduled time point at which the casing 30 is brought into the open state after the steam turbine 10 is operated sometime following a current time point.
A device for executing the method according to the present embodiment is essentially the same as the device 50 described with reference to
In the creep model receiving step S2 in the present embodiment, the creep model receiving unit 62 receives a creep model. As illustrated in
Similar to the condition receiving step S4 in the second embodiment, in the condition receiving step S4 in the present embodiment, in addition to the conditions received in the condition receiving step S4 in the first embodiment, the condition receiving unit 64 receives, as conditions, a pressure distribution and a temperature distribution in the casing 30, a temperature outside the casing 30, a thrust force applied to the stationary component, a linear expansion coefficient of the bolt 39 according to temperature, and linear expansion coefficients and heat transfer coefficients of the upper-half casing 30U and the lower-half casing 30L according to temperature when the steam turbine 10 is in operation. Further, the condition receiving unit 64 receives, as the conditions, an accumulated operation time of the steam turbine 10 until a current time point and an accumulated operation time of the steam turbine 10 until the casing 30 is brought into the open state after the steam turbine 10 is operated sometime following the current time point.
In the pressure distribution estimating step S6 in the present embodiment, the pressure distribution estimating unit 66 simulates the pressure distribution of the flange surface after creep deformation at a scheduled time point at which the casing 30 is brought into the open state after the steam turbine 10 is operated sometime following a current time point by using the conditions received in the condition receiving step S4.
Creep deformation until a current time point has been reflected in measured three-dimensional coordinate data received in the measured coordinate receiving step S3. Thus, as illustrated in
Also in the leakage evaluating step S7 in the present embodiment, the leakage evaluating unit 67 obtains the high leakage region 89 in which steam is highly likely to leak in the flange surface.
The present embodiment estimates the pressure distribution of the flange surface after creep deformation at a scheduled time point at which the casing 30 is brought into the open state after the steam turbine 10 is operated sometime following a current time point. Accordingly, in the present embodiment, it is possible to check the sealing performance in consideration of creep deformation when the steam turbine 10 is operated after the current time point.
Note that the creep model receiving step S2 may be executed at any stage before the modified model creating step S5.
As above, the embodiments of the present disclosure have been described in detail. However, the present disclosure is not limited by the embodiments described above. Various additions, changes, substitutions, partial deletions, and the like can be made without departing from the scope and the spirit of the present invention derived from the contents and equivalents thereof defined in the claims.
The methods for estimating a flange surface pressure distribution in a rotary machine according to the embodiments described above can be understood, for example, as follows.
The rotary machine includes: a rotor 15 rotatable around an axis Ar extending in a horizontal direction; a casing 30 in which a working fluid can flow and which covers an outer periphery of the rotor 15; and a stationary component disposed in the casing 30 and attached to the casing 30. The casing 30 includes an upper-half casing 30U on an upper side, a lower-half casing 30L on a lower side, and a plurality of bolts 39 fastening the upper-half casing 30U to the lower-half casing 30L. The upper-half casing 30U includes an upper flange 32U formed with an upper flange surface 33U facing downward. The lower-half casing 30L includes a lower flange 32L formed with a lower flange surface 33L facing upward and opposing the upper flange surface 33U in the vertical direction Dz. The upper flange 32U and the lower flange 32L include bolt holes 34 penetrating therethrough in the vertical direction Dz, and the respective plurality of bolts 39 can be inserted into the bolt holes 34.
The method for estimating a flange surface pressure distribution in the above rotary machine includes:
Conventionally, when the sealing performance between the upper flange 32U and the lower flange 32L is checked, a paint is first applied to one of check targets, and then the upper flange 32U is fastened to the lower flange 32L with bolts 39. Subsequently, the bolts 39 are removed, the upper-half casing 30U and the lower-half casing 30L are returned to the open state, and then the paint adhesion state of the remaining one of the check targets is checked. However, in the present aspect, the pressure distribution of one flange surface out of the upper flange surface 33U and the lower flange surface 33L when the casing 30 is brought into the fastened state is estimated. Accordingly, in the present aspect, in order to check the sealing performance between the upper flange 32U and the lower flange 32L, it is not necessary to bring the casing 30 in the open state into the fastened state and then return the casing 30 to the open state again, and thus it is possible to reduce the time and effort for checking the sealing performance.
In the present aspect, the pressure distribution of the one flange surface when the casing 30 is in the fastened state and the rotary machine is in operation is estimated. Accordingly, in the present aspect, the sealing performance when the rotary machine is in operation can be checked.
In the present aspect, the pressure distribution of the one flange surface after the change in the flow rate of the working fluid when the casing 30 is in the fastened state and the rotary machine is in operation is estimated. Accordingly, in the present aspect, the sealing performance after the change in the flow rate of the working fluid when the rotary machine is in operation can be checked. Therefore, the present aspect is effective for checking the sealing performance at the time of startup of the rotary machine and for checking the sealing performance when the flow rate of the working fluid flowing into the rotary machine rapidly changes.
The present aspect estimates the pressure distribution of the one flange surface after creep deformation at the scheduled time point at which the casing 30 is brought into the open state after the rotary machine is operated sometime following the current time point. Accordingly, in the present aspect, it is possible to check the sealing performance in consideration of creep deformation when the rotary machine is operated after the current time point.
The methods for evaluating leakage in a rotary machine according to the embodiments described above can be understood, for example, as follows.
In the present aspect, it is possible to easily check a region in the flange surface where the working fluid is highly likely to leak from between the upper flange surface 33U and the lower flange surface 33L. Accordingly, in the present aspect, the sealing performance can be checked more easily.
The programs for estimating a flange surface pressure distribution in a rotary machine according to the embodiments described above can be understood, for example, as follows.
The rotary machine includes: a rotor 15 rotatable around an axis Ar extending in a horizontal direction; a casing 30 in which a working fluid can flow and which covers an outer periphery of the rotor 15; and a stationary component disposed in the casing 30 and attached to the casing 30. The casing 30 includes an upper-half casing 30U on an upper side, a lower-half casing 30L on a lower side, and a plurality of bolts 39 fastening the upper-half casing 30U to the lower-half casing 30L. The upper-half casing 30U includes an upper flange 32U formed with an upper flange surface 33U facing downward. The lower-half casing 30L includes a lower flange 32L formed with a lower flange surface 33L facing upward and opposing the upper flange surface 33U in the vertical direction Dz. The upper flange 32U and the lower flange 32L include bolt holes 34 penetrating therethrough in the vertical direction Dz, and the respective plurality of bolts 39 can be inserted into the bolt holes 34.
The program for estimating a flange surface pressure distribution in the above rotary machine causes a computer to execute:
By causing the computer to execute the program according to the present aspect, the time and effort for checking the sealing performance between the upper flange surface 33U and the lower flange surface 33L can be reduced as in the method according to the first aspect.
By causing the computer to execute the program according to the present aspect, the sealing performance when the rotary machine is in operation can be checked as in the method according to the second aspect.
By causing the computer to execute the program according to the present aspect, the sealing performance when the rotary machine is in operation and after the change in the flow rate of the working fluid can be checked as in the method according to the third aspect.
By causing the computer to execute the program according to the present aspect, it is possible to check the sealing performance in consideration of creep deformation when the rotary machine is operated after the current time point as in the method according to the fourth aspect.
The program for evaluating leakage in a rotary machine according to the embodiments described above can be understood, for example, as follows.
By causing the computer to execute the program according to the present aspect, it is possible to easily check a region in the flange surface where the working fluid is highly likely to leak from between the upper flange surface 33U and the lower flange surface 33L as in the method according to the fifth aspect.
The devices for estimating a flange surface pressure distribution in a rotary machine according to the embodiments described above can be understood, for example, as follows.
The rotary machine includes: a rotor 15 rotatable around an axis Ar extending in a horizontal direction; a casing 30 in which a working fluid can flow and which covers an outer periphery of the rotor 15; and a stationary component disposed in the casing 30 and attached to the casing 30. The casing 30 includes an upper-half casing 30U on an upper side, a lower-half casing 30L on a lower side, and a plurality of bolts 39 fastening the upper-half casing 30U to the lower-half casing 30L. The upper-half casing 30U includes an upper flange 32U formed with an upper flange surface 33U facing downward. The lower-half casing 30L includes a lower flange 32L formed with a lower flange surface 33L facing upward and opposing the upper flange surface 33U in the vertical direction Dz. The upper flange 32U and the lower flange 32L include bolt holes 34 penetrating therethrough in the vertical direction Dz, and the respective plurality of bolts 39 can be inserted into the bolt holes 34.
A device for estimating a flange surface pressure distribution 50a in the above rotary machine includes:
Similar to the method according to the first aspect, in the present aspect, the time and effort for checking the sealing performance between the upper flange surface 33U and the lower flange surface 33L can be reduced.
Similar to the method according to the second aspect, in the present aspect, the sealing performance when the rotary machine is in operation can be checked.
Similar to the method according to the third aspect, in the present aspect, the sealing performance when the rotary machine is in operation and after the change in the flow rate of the working fluid can be checked.
By causing the computer to execute the program according to the present aspect, it is possible to check the sealing performance in consideration of creep deformation when the rotary machine is operated after the current time point as in the method according to the fourth aspect.
The device for evaluating leakage in a rotary machine according to the embodiments described above can be understood, for example, as follows.
Similar to the method according to the fifth aspect, in the present aspect, it is possible to easily check a region in the flange surface where the working fluid is highly likely to leak from between the upper flange surface 33U and the lower flange surface 33L.
According to one aspect of the present disclosure, a flange surface pressure distribution in a rotary machine can be estimated, and thus the time and effort for checking the sealing performance between the two flanges can be reduced.
Number | Date | Country | Kind |
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2022-027441 | Feb 2022 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2022/044208 | 11/30/2022 | WO |