CN107780983B - Turbine inner cylinder structure - Google Patents
Turbine inner cylinder structure Download PDFInfo
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- CN107780983B CN107780983B CN201710929709.3A CN201710929709A CN107780983B CN 107780983 B CN107780983 B CN 107780983B CN 201710929709 A CN201710929709 A CN 201710929709A CN 107780983 B CN107780983 B CN 107780983B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
- F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
- F01D25/26—Double casings; Measures against temperature strain in casings
- F01D25/265—Vertically split casings; Clamping arrangements therefor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
- F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
- F01D25/246—Fastening of diaphragms or stator-rings
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- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
The invention discloses a turbine inner cylinder structure, which comprises an inner cylinder body, wherein the inner cylinder body is provided with more than two cylindrical cylinder body sections and a plurality of pull rod bolts, a plurality of bolt holes are formed in the wall thickness circumference of each cylinder body section, the bolt holes in the circumference of each cylinder body section are in one-to-one correspondence in the axial direction, the cylinder body sections of the inner cylinder body are sequentially butted in the axial direction, the bolt holes in the circumferential direction are in correspondence in the axial direction, each pull rod bolt is penetrated and locked in the bolt holes in the axial correspondence of the cylinder body sections, and the pull rod bolts of the inner cylinder body respectively lock the cylinder body sections into a whole in the axial direction to form a complete cylindrical inner cylinder. The invention has small outer diameter, compact structure, good sealing performance and high bearing strength, is beneficial to improving the sealing and bearing performance of the outer cylinder matched with the outer cylinder, and can completely meet the technical requirements of high-parameter steam turbines, particularly high-parameter steam turbines.
Description
Technical Field
The invention relates to a turbine inner cylinder structure.
Background
Turbine plants require the energy conversion of a fluid medium, such as a steam turbine, to be carried out by means of a cylinder block. In general, a high-pressure part of a steam turbine, especially a large steam turbine, adopts a double-cylinder structure, that is, an inner cylinder and an outer cylinder respectively bear a part of pressure difference and temperature difference of a fluid medium. As can be seen, the inner casing is one of the core components of the turbine plant, the steam turbine.
At present, the turbine inner cylinder mainly has two structural forms. One is a horizontal split surface locking structure, namely the upper half of the inner cylinder and the lower half of the inner cylinder are locked into a whole in the vertical direction (namely the upper direction and the lower direction, the same direction below) through high-strength bolts on a horizontal split surface flange; the second is a thermal lantern ring fastening structure, namely, the upper half of the semi-cylindrical inner cylinder and the lower half of the inner cylinder are fastened into a cylindrical structure without a flange structure through the thermal lantern ring sleeved outside. In the two structures, the first one has the worst pressure bearing capacity, and the second one has the best pressure bearing capacity than the first one. However, the two inner cylinder structures can increase the outer contour dimension of the inner cylinder, and further increase the outer contour dimension of the outer cylinder matched with the inner cylinder, so that under the condition of the same wall thickness and the same split bolt locking force, the sealing capability of the outer cylinder is reduced, the sealing reliability is deteriorated, and the bearable differential pressure and temperature difference are low.
In recent years, in order to improve the energy conversion efficiency of a power station power generation system, the main steam parameters of a power station steam turbine are higher and higher, the main steam pressure of an ultra-supercritical steam turbine which is put into operation in China at present reaches 31MPa, the main steam temperature also reaches 620 ℃, and the ultra-supercritical steam turbine with the main steam pressure of 35 MPa or more is vigorously developed by domestic main steam turbine manufacturers. The large-sized turbine high-pressure cylinder has large volume flow, and the outer diameter of the outer cylinder of the large-sized turbine high-pressure cylinder is often over phi 2000mm due to the structure and other limiting factors, so that the sealing technical difficulty of the large-sized high-pressure cylinder is very high, and the conventional turbine inner cylinder structure is difficult to meet the technical requirements of the high-parameter turbine high-pressure cylinder.
In order to improve the pressure bearing capacity of the high-pressure cylinder of the steam turbine, there have been attempts to manufacture and mold the high-pressure cylinder of the steam turbine in a manner of axially segmenting and bolt-combining, for example, "a steam turbine structure" (publication No. CN 102383879 a, publication No. 2012.03.21), "a steam turbine cylinder structure" (publication No. CN 203978525U, publication No. 2014.12.03) disclosed in chinese patent literature. These prior art techniques have been constructed by axially dividing the high pressure cylinder (inner and/or outer) of the steam turbine into left and right sections and then axially locking the sections together by high strength bolts. However, in these prior arts, the axially-segmented cylinder bodies are axially locked and connected, which must be realized by a radially-outward-protruding flange structure on the butt joint surface of the left and right two-segment cylinder bodies, and the existence of the flange structure will inevitably increase the structural volume of the cylinder, so that the structural volume of the cylinder is not compact enough, and further, the sealing performance and the pressure-bearing strength of the cylinder in use can be reduced, and the technical requirements of the high-parameter turbine high-pressure cylinder are still difficult to meet.
Disclosure of Invention
The technical purpose of the invention is as follows: aiming at the defects of the prior art, the turbine inner cylinder structure has the advantages of compact structure, good sealing performance and strong bearing capacity, and can meet the technical requirements of high parameters.
The technical scheme adopted by the invention for realizing the technical purpose is as follows: the utility model provides a cylinder structure in turbine, includes interior cylinder body, interior cylinder body has cylinder type cylinder section and a plurality of pull rod bolt more than two, has seted up on the wall thickness circumference of each cylinder section and has arranged a plurality of bolt hole, and the bolt hole on each cylinder section circumference is in the axial one-to-one, these cylinder sections of interior cylinder body dock in order in the axial, make each bolt hole on circumference correspond in the axial, and each pull rod bolt wears to adorn the bolt hole of locking in the axial correspondence of these cylinder sections, these pull rod bolts of interior cylinder body are respectively in the axial with each cylinder section lock synthetic whole, form complete cylinder type interior cylinder.
As one of the preferable schemes, the cylinder body section of the inner cylinder body is divided into sections at least according to the stationary blade assembly of each stage; or the cylinder body section of the inner cylinder body is divided into sections correspondingly at least according to each stage of stationary blade assembly and steam inlet chamber; and the pull rod bolt of the inner cylinder body axially penetrates from the corresponding bolt hole on the steam exhaust side and extends to the steam inlet side for locking.
As one preferable scheme, the abutting surfaces of the adjacent cylinder sections of the inner cylinder body are circumferentially provided with mutually corresponding sealing grooves, sealing rings are embedded in the mutually corresponding sealing grooves, and the sealing rings are blocked and sealed on the axial abutting surfaces of the adjacent cylinder sections. Furthermore, the sealing grooves corresponding to each other on the abutting surfaces of the adjacent cylinder body sections are two, and the two sealing grooves are arranged on the inner side and the outer side of the bolt hole of the cylinder body section. The sealing ring is an L-shaped sealing ring folded inwards.
Preferably, the inner wall of the cylinder section is provided with radial protruding limiting convex teeth and adjusting convex teeth, the limiting convex teeth are distributed on the left side and the right side of a horizontal position and correspond to the end parts of the middle facets of the static blade assemblies combined by the horizontal middle facets, the adjusting convex teeth are distributed on the two sides of the top and the bottom of a space position and correspond to the top and the bottom of the static blade assemblies combined by the horizontal middle facets, the periphery of each static blade assembly is provided with an embedded groove corresponding to the convex teeth on the cylinder section, and the outline structure of the embedded groove on each static blade assembly is larger than the outline structure of the corresponding convex teeth on the cylinder section.
Preferably, the outer end of the draw rod bolt is connected with a spherical washer assembly and a lock nut.
Preferably, the outer end of the pull rod bolt is provided with a central hole which is of an axial blind hole-shaped structure and is used for heat supply.
Preferably, the minimum inner diameter of each cylinder section of the inner cylinder body is greater than the maximum outer diameter of the matched rotor assembly.
The beneficial technical effects of the invention are as follows:
1. the invention effectively eliminates the structure of the middle-divided sealing surface, and a flange structure is not required to be arranged on the butt joint surface, and the circumferential structure is basically symmetrical, thereby the structure volume is compact, and the structural stress and the thermal stress are small; compared with the prior art, under the condition of the same meridian passage, the radial turbine radial vane has the advantages of small outer diameter size, compact structure, good sealing performance and high pressure bearing strength, is favorable for improving the sealing and pressure bearing performance of an outer cylinder matched with the radial vane; in addition, each cylinder section can be manufactured and molded by adopting a forging piece, so that the material performance of the cylinder section can be greatly improved, the structure is simpler and lighter, and the sealing capability and the bearing strength are further effectively improved;
2. the specific segmented structure of the cylinder body section can effectively ensure that the static blade assembly is simple, easy and easy to assemble in the cylinder body section, the assembly technical difficulty is reduced, and the operability is strong; in addition, under the assistance of the convex tooth structure on the cylinder body section, the assembled stator blade assembly can be effectively ensured to be accurately, stably and reliably assembled in the cylinder body section;
3. the sealing butt joint structure between the adjacent cylinder body sections can further and reliably improve the sealing performance and the pressure-bearing capacity of the invention, and particularly has more pertinence to the high-pressure area of the invention;
4. the locking structure of the stay bolt on the cylinder body section can effectively and obviously improve the stress condition of the stay bolt, which is more obvious and outstanding especially under the matching of a hot-pressing structure, and the locking force is excellent;
5. the corresponding relation between the invention and the matched rotor assembly can effectively reduce the technical difficulty of assembly between the invention and the rotor assembly, and has strong operability.
Drawings
FIG. 1 is a schematic diagram of an embodiment of the present invention.
Fig. 2 is a sectional view a-a of fig. 1.
Fig. 3 is an enlarged view of a portion I in fig. 1.
The reference numbers in the figures mean: 1-a rotor assembly; 2, limiting convex teeth; 3-a steam inlet chamber; 4-stay bolt; 5-cylinder section; 6, sealing rings; 7-stationary blade assembly; 8, sealing grooves; 9-a central hole; 10-a spherical washer assembly; 11-a locking nut; 12-horizontal bisection; 13-exhaust steam guide ring; 14-adjusting the convex teeth; r1 — maximum outer diameter of rotor assembly; r2 — smallest inner diameter of cylinder block section.
Detailed Description
The present invention relates to an inner cylinder structure of a turbine, and more particularly to an inner cylinder structure of a steam turbine having high parameters (for example, main steam pressure of 31MPa or more, particularly 35 MPa or more, and main steam temperature of 620 ℃ or more). The technical contents of the present invention are clearly and clearly described in the following embodiments, wherein embodiment 1 is combined with the drawings of the specification, namely fig. 1, fig. 2 and fig. 3, to clearly and clearly describe the technical contents of the present invention, and although other embodiments are not separately drawn, the main structure of the embodiments can still refer to the drawings of embodiment 1.
Example 1
Referring to fig. 1, 2 and 3, the present invention comprises an inner cylinder body having a plurality of cylindrical cylinder sections 5 and a number of stay bolts 4.
The cylinder section 5 of the inner cylinder body is correspondingly divided into sections according to the relative positions of the stationary blade assemblies 7 and the steam inlet chamber 3, that is, the inner cylinder body is divided into a plurality of cylinder sections 5 according to the stationary blade assemblies 7, and the cylinder section corresponding to the first stage stationary blade assembly is separated from the steam inlet chamber 3 (specifically, the steam inlet chamber 3 is also a cylinder section in a broad sense, and the steam inlet chamber 3 is arranged in another row for clarity), and the first stage stationary blade assembly 7 is correspondingly installed on each cylinder section 5. A plurality of bolt holes (specifically, through hole structures for penetrating and installing the tie bolts) are formed in the circumference of the wall thickness of each cylinder section 5, a plurality of bolt holes (specifically, wire-planting structures for locking the tie bolts) are also formed in the circumference of the wall thickness of the steam inlet chamber 3, the bolt holes in the circumference of each cylinder section 5 are in one-to-one correspondence in the axial direction, and the bolt holes in the circumference of the steam inlet chamber 3 are in one-to-one correspondence with the bolt holes in the circumference of the cylinder section 5 in the axial direction.
Since each of the cylinder sections 5 corresponds to each stage of the vane assembly 7, it is necessary to install the corresponding vane assembly 7 in each of the cylinder sections 5; since each of the cylinder segments 5 has an annular cylindrical structure, each stage of the vane assembly is divided into upper and lower halves, and a horizontal median plane 12 is provided between the upper and lower halves of the vane assembly, in order to facilitate the installation of the vane assembly 7. Therefore, the inner wall of each cylinder section 5 is provided with a radially convex limiting convex tooth 2 and an adjusting convex tooth 14 corresponding to the first stage stationary blade assembly half body; the limiting convex teeth 2 are distributed on the left side and the right side of the horizontal position, namely two limiting convex teeth 2 corresponding to the upper half and the lower half of the static blade assembly are distributed near the horizontal median plane 12 of the upper half and the lower half of the static blade assembly (of course, the limiting convex teeth 2 are close to one side of the corresponding half body), so that the limiting convex teeth 2 correspond to the ends of the median plane of the static blade assembly 7 combined by the horizontal median plane 12; the adjusting teeth 14 are distributed on the top/bottom side in the upper/lower direction, that is, one adjusting tooth 14 corresponding to the upper/lower half of the vane assembly, and are distributed on the top of the upper/lower half of the vane assembly, that is, on the top or bottom side of the inner wall of the cylinder section 5, so that the adjusting teeth 14 correspond to the top/bottom of the vane assembly 7 combined with the horizontal midportion 12. Based on the mounting structure of the cylinder section 5, the periphery of the corresponding stationary blade assembly 7 is provided with an embedded groove corresponding to the convex teeth on the cylinder section 5, specifically, two embedded grooves corresponding to the limiting convex teeth 2 are arranged at the two ends of the periphery of the upper half of the stationary blade assembly 7, an embedded groove corresponding to the adjusting convex teeth 14 is arranged at the top of the periphery, two embedded grooves corresponding to the limiting convex teeth 2 are arranged at the two ends of the periphery of the lower half of the stationary blade assembly 7, and an embedded groove corresponding to the adjusting convex teeth 14 is arranged at the bottom of the periphery; the inside diameter of the embedded slot on the vane assembly 7 should be slightly larger than the inside diameter of the bearing surface of the cylinder section 5, so as to ensure a certain radial sealing width between the assembled vane assembly 7 and the cylinder section 5. With such an assembly structure, each stage of stator blade assembly 7 is assembled in the corresponding cylinder section 5, the limiting convex teeth 2 correspond to the half bodies of the stator blade assemblies 7 and play roles of suspension and support, and the adjusting convex teeth 14 correspond to the half bodies of the stator blade assemblies 7 and play roles of adjusting the left and right positions.
The cylinder sections 5 with the corresponding stationary blade assemblies 7 and the steam inlet chamber 3 are sequentially butted in the axial direction, so that bolt holes in the circumferential direction of the cylinder sections are in one-to-one correspondence in the axial direction, and the final-stage cylinder section is connected with a steam exhaust guide ring 13. In order to ensure the sealing performance of the axial butt joint of the cylinder body and the cylinder body, sealing grooves 8 which correspond to each other are circumferentially arranged on the butt joint surface of the adjacent cylinder body section 5 in the high-pressure area of the formed inner cylinder body, specifically, the sealing grooves which correspond to each other are circumferentially arranged on the butt joint surface of the steam inlet chamber and the first-stage cylinder body section (when the butt joint surfaces of the steam inlet chamber and the first-stage cylinder body section are jointed, the sealing grooves which correspond to each other form a complete sealing ring groove), the sealing grooves which correspond to each other are circumferentially arranged on the butt joint surface of the first-stage cylinder body section and the second; for further improving the sealing effect, the sealing grooves 8 corresponding to each other on the abutting surfaces of the adjacent cylinder segments 5 are two, and the two sealing grooves 8 are arranged on the inner side and the outer side of the bolt holes of the cylinder segments 5, that is, one sealing groove 8 corresponding to each other is arranged on the inner side of the bolt holes of the cylinder segments 5, and the other sealing groove 8 corresponding to each other is arranged on the outer side of the bolt holes of the cylinder segments 5. And sealing rings 6 are embedded in the corresponding sealing grooves 8, the sealing rings 6 are inwards folded sealing rings with L-shaped sections, and the sealing rings 6 are blocked and sealed on the axial butt joint surfaces of the adjacent cylinder sections 5.
The axial length of each tie bolt 4 is greater than the sum of the axial lengths of the cylinder sections 5 of the inner cylinder body. Each pull rod bolt 4 axially penetrates through a corresponding bolt hole on the steam exhaust side, namely a corresponding bolt hole of the cylinder body section 5 at the steam exhaust guide ring 13, and extends in the corresponding bolt hole of each cylinder body section 5 step by step until the pull rod bolt extends to a corresponding bolt hole on the steam inlet side, namely a corresponding bolt hole of the steam inlet chamber 3 for locking; the outer end of each tie bolt 4 is connected with a spherical washer component 10 and a locking nut 11 on the end surface of the cylinder body section 5 at the position of the steam exhaust guide ring 13, and the outward extension length of the tie bolt 4 and the components thereof is basically flush with the outer end of the steam exhaust guide ring 13. In order to enhance the locking force of the stay bolts 4 and improve the stress state, the outer end of each stay bolt 4 is provided with a central hole 9 which has an axial blind hole-shaped structure and is used for tightly supplying heat. The pull rod bolts 4 achieve axial locking on the cylinder sections 5 and the steam inlet chamber 3, and simultaneously play a positioning role, so that the radial and circumferential positions of the cylinder sections 5 and the steam inlet chamber 3 are ensured, and the concentricity of the cylinder sections of the inner cylinder body is ensured.
In this way, the stay bolts 4 of the inner cylinder body axially lock the cylinder sections 5 and the steam inlet chamber 3 together to form a complete cylindrical inner cylinder without a split surface.
Of course, when the cylinder sections 5 with the corresponding stationary blade assemblies 7 and the steam inlet chamber 3 are axially combined and connected, the assembling corresponding to the rotor assembly 1 should be performed synchronously, and in order to facilitate the assembling of the rotor assembly 1 in the inner cylinder body, it is required that the minimum inner diameter R2 of each cylinder section 5 should be slightly larger than the maximum outer diameter R1 of the matched rotor assembly 1, and this diameter difference should not affect the assembling of the inner cylinder body and the rotor assembly 1.
In order to ensure circumferential symmetry of the inner cylinder structure, the bolt holes in the cylinder block sections 5 and the inlet chamber 3 are preferably evenly distributed in the circumferential direction.
Example 2
The present invention includes an inner cylinder body having a plurality of cylindrical cylinder sections and a plurality of tie bolts.
The cylinder body section of the inner cylinder body is correspondingly divided into sections according to the relative positions of all stages of static blade assemblies, namely, the inner cylinder body is divided into a plurality of cylinder body sections according to all stages of static blade assemblies, the cylinder body section corresponding to the first stage of static blade assembly and the steam inlet chamber are of an integrated structure, and each cylinder body section is correspondingly provided with one stage of static blade assembly. A plurality of bolt holes are formed in the circumference of the wall thickness of each cylinder section, the bolt holes in the cylinder section corresponding to the first-stage stationary blade assembly are of a wire planting structure, the bolt holes in other cylinder sections are of a through hole structure, and the bolt holes in the circumference of each cylinder section are in one-to-one correspondence in the axial direction.
Because each cylinder section corresponds to each stage of stationary blade assembly, the corresponding stationary blade assembly needs to be installed in each cylinder section; since each cylinder section has an annular cylindrical structure, each stage of the stator blade assembly is divided into an upper half and a lower half for facilitating installation of the stator blade assembly, and a horizontal split surface is provided between the stator blade assemblies of the upper half and the lower half. Therefore, the inner wall of each cylinder section is provided with a radially convex limiting convex tooth and an adjusting convex tooth which correspond to the first-stage stationary blade assembly half body; the limiting convex teeth are distributed on the left side and the right side of the horizontal position, namely two limiting convex teeth corresponding to the upper half and the lower half of the static blade assembly are distributed near the horizontal bisection plane of the upper half and the lower half of the static blade assembly (certainly, the limiting convex teeth are close to one side of the corresponding half body), so that the limiting convex teeth correspond to the ends of the bisection plane of the static blade assembly combined by the horizontal bisection plane; the adjusting convex teeth are distributed on the top side/bottom side of the heaven and earth position, namely the top side/bottom side in the up-down direction, namely one adjusting convex tooth corresponding to the upper half/lower half of the static blade assembly is distributed on the top of the upper half/lower half of the static blade assembly, namely the top side or bottom side of the inner wall of the cylinder section, so that the adjusting convex teeth correspond to the top/bottom of the static blade assembly combined in a horizontal split surface. Based on the mounting structure of the cylinder section, the periphery of the corresponding static blade assembly is provided with an embedded groove corresponding to the convex teeth on the cylinder section, specifically, the two ends of the periphery of the upper half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, the top of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth, the two ends of the periphery of the lower half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, and the bottom of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth; the inner diameter of the embedded groove on the static blade assembly is slightly larger than that of the bearing surface of the cylinder body, so that a certain radial sealing width is ensured between the static blade assembly and the cylinder body section which are assembled together. With the assembly structure, each stage of the stator blade assembly is assembled in the corresponding cylinder body section, the limiting convex teeth correspond to the half bodies of the stator blade assembly and play roles in suspension and support, the adjusting convex teeth correspond to the half bodies of the stator blade assembly and play roles in adjusting the left position and the right position,
the cylinder sections with the corresponding stationary blade assemblies are sequentially butted in the axial direction, so that bolt holes in the circumferential direction of the cylinder sections are in one-to-one correspondence in the axial direction, and the final-stage cylinder section is connected with a steam exhaust guide ring. In order to ensure the sealing performance of the axial butt joint of the cylinder sections, the circumferential direction of the butt joint surface of the adjacent cylinder section in the high-pressure area of the formed inner cylinder body is provided with mutually corresponding sealing grooves, specifically, the circumferential direction of the butt joint surface of the first-stage cylinder section and the second-stage cylinder section is provided with mutually corresponding sealing grooves (when the butt joint surfaces of the first-stage cylinder section and the second-stage cylinder section are jointed, the mutually corresponding sealing grooves form a complete sealing ring groove), the circumferential direction of the butt joint surface of the second-stage cylinder section and the third-stage cylinder section is provided with mutually corresponding sealing grooves, and the like; for further improvement sealed effect, the mutual seal groove that corresponds on the butt joint face of adjacent cylinder block section is twice, and this twice seal groove is arranged in the bolt hole inboard and the outside of cylinder block section, and one mutual seal groove that corresponds is inboard at the bolt hole of cylinder block section promptly, and another mutual seal groove that corresponds is in the bolt hole outside of cylinder block section. Sealing rings are embedded in the corresponding sealing grooves and are folded inwards, the cross sections of the sealing rings are L-shaped, and the sealing rings are blocked and sealed on the axial butt joint surfaces of the adjacent cylinder body sections.
The axial length of each tie bolt is greater than the sum of the axial lengths of the cylinder sections of the inner cylinder body. Each pull rod bolt axially penetrates through a corresponding bolt hole on the steam exhaust side, namely a corresponding bolt hole of the cylinder body section at the steam exhaust guide ring, and extends in the corresponding bolt hole of each cylinder body section step by step until the pull rod bolt extends to a corresponding bolt hole on the steam inlet side, namely a corresponding bolt hole of the first-stage cylinder body section and is locked; the outer end of each pull rod bolt is connected with a spherical washer component and a locking nut on the end surface of the cylinder body section at the steam exhaust guide ring, and the outward extension length of the pull rod bolt and the components thereof is basically flush with the outer end of the steam exhaust guide ring. In order to strengthen the locking force of the pull rod bolts and improve the stress state, the outer end of each pull rod bolt is provided with a central hole which is in an axial blind hole-shaped structure and can supply heat tightly. The pull rod bolts achieve axial locking on each cylinder body section and play a role in positioning so as to ensure the radial and circumferential positions of each cylinder body section and ensure the concentricity of each section of the inner cylinder body.
In this way, the stay bolts of the inner cylinder body respectively lock the cylinder sections into a whole in the axial direction, forming a complete cylindrical inner cylinder without a split surface.
Of course, when the cylinder sections with the corresponding stationary blade assemblies are axially combined and connected, the assembly of the corresponding rotor assemblies should be performed synchronously, and in order to facilitate the assembly of the rotor assemblies in the inner cylinder body, the minimum inner diameter of each cylinder section should be slightly larger than the maximum outer diameter of the matched rotor assemblies, and the diameter difference should not affect the assembly of the inner cylinder body and the rotor assemblies.
In order to ensure circumferential symmetry of the inner cylinder structure, the bolt holes in the cylinder sections are preferably evenly distributed in the circumferential direction.
Example 3
The present invention includes an inner cylinder body having a plurality of cylindrical cylinder sections and a plurality of tie bolts.
The cylinder section of the inner cylinder body is correspondingly divided into sections according to the relative position of one-stage to two-stage static blade assemblies, specifically, the cylinder section corresponding to the first-stage static blade assembly and the steam inlet chamber are of an integrated structure, the second-stage and third-stage static blade assemblies correspond to one cylinder section, the fourth-stage and fifth-stage static blade assemblies correspond to one cylinder section, and so on, so that other cylinder sections outside the first-stage cylinder section respectively correspond to the two-stage static blade assemblies, and the stage number of the static blade assembly corresponding to the cylinder section of the last stage is randomly determined according to the stage number of the total static blade assembly. A plurality of bolt holes are formed in the circumference of the wall thickness of each cylinder section, the bolt holes in the cylinder section corresponding to the first-stage stationary blade assembly are of a wire planting structure, the bolt holes in other cylinder sections are of a through hole structure, and the bolt holes in the circumference of each cylinder section are in one-to-one correspondence in the axial direction.
Because each cylinder section corresponds to each stage of stationary blade assembly, the corresponding stationary blade assembly needs to be installed in each cylinder section; since each cylinder section has an annular cylindrical structure, each stage of the stator blade assembly is divided into an upper half and a lower half for facilitating installation of the stator blade assembly, and a horizontal split surface is provided between the stator blade assemblies of the upper half and the lower half. Therefore, the inner wall of each cylinder section is provided with a limiting convex tooth and an adjusting convex tooth which are capable of installing the corresponding stage static blade assembly half bodies and are convex in the radial direction according to the installation position of the corresponding static blade assembly; the limiting convex teeth are distributed on the left side and the right side of the horizontal position, namely two limiting convex teeth corresponding to the upper half and the lower half of the static blade assembly are distributed near the horizontal bisection plane of the upper half and the lower half of the static blade assembly (certainly, the limiting convex teeth are close to one side of the corresponding half body), so that the limiting convex teeth correspond to the ends of the bisection plane of the static blade assembly combined by the horizontal bisection plane; the adjusting convex teeth are distributed on the top side/bottom side of the heaven and earth position, namely the top side/bottom side in the up-down direction, namely one adjusting convex tooth corresponding to the upper half/lower half of the static blade assembly is distributed on the top of the upper half/lower half of the static blade assembly, namely the top side or bottom side of the inner wall of the cylinder section, so that the adjusting convex teeth correspond to the top/bottom of the static blade assembly combined in a horizontal split surface. Based on the mounting structure of the cylinder section, the periphery of the corresponding static blade assembly is provided with an embedded groove corresponding to the convex teeth on the cylinder section, specifically, the two ends of the periphery of the upper half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, the top of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth, the two ends of the periphery of the lower half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, and the bottom of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth; the inner diameter of the embedded groove on the static blade assembly is slightly larger than that of the bearing surface of the cylinder body, so that a certain radial sealing width is ensured between the static blade assembly and the cylinder body section which are assembled together. With such assembly structure, each grade of quiet leaf subassembly assembly is in the cylinder body section that corresponds, and spacing dogtooth corresponds the halfbody of quiet leaf subassembly, plays suspension, support effect, and the adjustment dogtooth corresponds the halfbody of quiet leaf subassembly and plays the effect of adjusting left and right position.
The cylinder sections with the corresponding stationary blade assemblies are sequentially butted in the axial direction, so that bolt holes in the circumferential direction of the cylinder sections are in one-to-one correspondence in the axial direction, and the final-stage cylinder section is connected with a steam exhaust guide ring. In order to ensure the sealing performance of the axial butt joint of the cylinder sections, the circumferential direction of the butt joint surface of the adjacent cylinder section in the high-pressure area of the formed inner cylinder body is provided with mutually corresponding sealing grooves, specifically, the circumferential direction of the butt joint surface of the first-stage cylinder section and the second-stage cylinder section is provided with mutually corresponding sealing grooves (when the butt joint surfaces of the first-stage cylinder section and the second-stage cylinder section are jointed, the mutually corresponding sealing grooves form a complete sealing ring groove), the circumferential direction of the butt joint surface of the second-stage cylinder section and the third-stage cylinder section is provided with mutually corresponding sealing grooves, and the like; for further improvement sealed effect, the mutual seal groove that corresponds on the butt joint face of adjacent cylinder block section is twice, and this twice seal groove is arranged in the bolt hole inboard and the outside of cylinder block section, and one mutual seal groove that corresponds is inboard at the bolt hole of cylinder block section promptly, and another mutual seal groove that corresponds is in the bolt hole outside of cylinder block section. Sealing rings are embedded in the corresponding sealing grooves and are folded inwards, the cross sections of the sealing rings are L-shaped, and the sealing rings are blocked and sealed on the axial butt joint surfaces of the adjacent cylinder body sections.
The axial length of each tie bolt is greater than the sum of the axial lengths of the cylinder sections of the inner cylinder body. Each pull rod bolt axially penetrates through a corresponding bolt hole on the steam exhaust side, namely a corresponding bolt hole of the cylinder body section at the steam exhaust guide ring, and extends in the corresponding bolt hole of each cylinder body section step by step until the pull rod bolt extends to a corresponding bolt hole on the steam inlet side, namely a corresponding bolt hole of the first-stage cylinder body section and is locked; the outer end of each pull rod bolt is connected with a spherical washer component and a locking nut on the end surface of the cylinder body section at the steam exhaust guide ring, and the outward extension length of the pull rod bolt and the components thereof is basically flush with the outer end of the steam exhaust guide ring. In order to strengthen the locking force of the pull rod bolts and improve the stress state, the outer end of each pull rod bolt is provided with a central hole which is in an axial blind hole-shaped structure and can supply heat tightly. The pull rod bolts achieve axial locking on each cylinder body section and play a role in positioning so as to ensure the radial and circumferential positions of each cylinder body section and ensure the concentricity of each section of the inner cylinder body.
In this way, the stay bolts of the inner cylinder body respectively lock the cylinder sections into a whole in the axial direction, forming a complete cylindrical inner cylinder without a split surface.
Of course, when the cylinder sections with the corresponding stationary blade assemblies are axially combined and connected, the assembly of the corresponding rotor assemblies should be performed synchronously, and in order to facilitate the assembly of the rotor assemblies in the inner cylinder body, the minimum inner diameter of each cylinder section should be slightly larger than the maximum outer diameter of the matched rotor assemblies, and the diameter difference should not affect the assembly of the inner cylinder body and the rotor assemblies.
In order to ensure circumferential symmetry of the inner cylinder structure, the bolt holes in the cylinder sections are preferably evenly distributed in the circumferential direction.
Example 4
The present invention includes an inner cylinder body having a plurality of cylindrical cylinder sections and a plurality of tie bolts.
The cylinder body section of the inner cylinder body is correspondingly divided into sections according to the relative positions of all stages of static blade assemblies, namely, the inner cylinder body is divided into a plurality of cylinder body sections according to all stages of static blade assemblies, the cylinder body section corresponding to the first stage of static blade assembly and the steam inlet chamber are of an integrated structure, and each cylinder body section is correspondingly provided with one stage of static blade assembly. A plurality of bolt holes are formed in the circumference of the wall thickness of each cylinder section, the bolt holes in the cylinder section corresponding to the first-stage stationary blade assembly are of a wire planting structure, the bolt holes in other cylinder sections are of a through hole structure, and the bolt holes in the circumference of each cylinder section are in one-to-one correspondence in the axial direction.
Because each cylinder section corresponds to each stage of stationary blade assembly, the corresponding stationary blade assembly needs to be installed in each cylinder section; since each cylinder section has an annular cylindrical structure, each stage of the stator blade assembly is divided into an upper half and a lower half for facilitating installation of the stator blade assembly, and a horizontal split surface is provided between the stator blade assemblies of the upper half and the lower half. Therefore, the inner wall of each cylinder section is provided with a radially convex limiting convex tooth and an adjusting convex tooth which correspond to the first-stage stationary blade assembly half body; the limiting convex teeth are distributed on the left side and the right side of the horizontal position, namely two limiting convex teeth corresponding to the upper half and the lower half of the static blade assembly are distributed near the horizontal bisection plane of the upper half and the lower half of the static blade assembly (certainly, the limiting convex teeth are close to one side of the corresponding half body), so that the limiting convex teeth correspond to the ends of the bisection plane of the static blade assembly combined by the horizontal bisection plane; the adjusting convex teeth are distributed on the top side/bottom side of the heaven and earth position, namely the top side/bottom side in the up-down direction, namely one adjusting convex tooth corresponding to the upper half/lower half of the static blade assembly is distributed on the top of the upper half/lower half of the static blade assembly, namely the top side or bottom side of the inner wall of the cylinder section, so that the adjusting convex teeth correspond to the top/bottom of the static blade assembly combined in a horizontal split surface. Based on the mounting structure of the cylinder section, the periphery of the corresponding static blade assembly is provided with an embedded groove corresponding to the convex teeth on the cylinder section, specifically, the two ends of the periphery of the upper half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, the top of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth, the two ends of the periphery of the lower half of the static blade assembly are provided with two embedded grooves corresponding to the limiting convex teeth, and the bottom of the periphery is provided with one embedded groove corresponding to the adjusting convex teeth; the inner diameter of the embedded groove on the static blade assembly is slightly larger than that of the bearing surface on the cylinder section, so that a certain radial sealing width is ensured between the static blade assembly and the cylinder section which are assembled together. With the assembly structure, each stage of the stator blade assembly is assembled in the corresponding cylinder body section, the limiting convex teeth correspond to the half bodies of the stator blade assembly and play roles in suspension and support, the adjusting convex teeth correspond to the half bodies of the stator blade assembly and play roles in adjusting the left position and the right position,
the cylinder sections with the corresponding stationary blade assemblies are sequentially butted in the axial direction, so that bolt holes in the circumferential direction of the cylinder sections are in one-to-one correspondence in the axial direction, and the final-stage cylinder section is connected with a steam exhaust guide ring. In order to ensure the sealing performance of the axial butt joint of the cylinder sections, the butt joint surfaces of the adjacent cylinder sections are circumferentially provided with mutually corresponding sealing grooves, specifically, the butt joint surfaces of the first-stage cylinder section and the second-stage cylinder section are circumferentially provided with mutually corresponding sealing grooves (when the butt joint surfaces of the first-stage cylinder section and the second-stage cylinder section are jointed, the mutually corresponding sealing grooves form a complete sealing ring groove), and the butt joint surfaces of the second-stage cylinder section and the third-stage cylinder section are circumferentially provided with mutually corresponding sealing grooves, and so on; for further improvement sealed effect, the mutual seal groove that corresponds on the butt joint face of adjacent cylinder block section is twice, and this twice seal groove is arranged in the bolt hole inboard and the outside of cylinder block section, and one mutual seal groove that corresponds is inboard at the bolt hole of cylinder block section promptly, and another mutual seal groove that corresponds is in the bolt hole outside of cylinder block section. Sealing rings are embedded in the corresponding sealing grooves and are folded inwards, the cross sections of the sealing rings are L-shaped, and the sealing rings are blocked and sealed on the axial butt joint surfaces of the adjacent cylinder body sections.
The axial length of each tie bolt is greater than the sum of the axial lengths of the cylinder sections of the inner cylinder body. Each pull rod bolt axially penetrates through a corresponding bolt hole on the steam exhaust side, namely a corresponding bolt hole of the cylinder body section at the steam exhaust guide ring, and extends in the corresponding bolt hole of each cylinder body section step by step until the pull rod bolt extends to a corresponding bolt hole on the steam inlet side, namely a corresponding bolt hole of the first-stage cylinder body section and is locked; the outer end of each pull rod bolt is connected with a spherical washer component and a locking nut on the end surface of the cylinder body section at the steam exhaust guide ring, and the outward extension length of the pull rod bolt and the components thereof is basically flush with the outer end of the steam exhaust guide ring. In order to strengthen the locking force of the pull rod bolts and improve the stress state, the outer end of each pull rod bolt is provided with a central hole which is in an axial blind hole-shaped structure and can supply heat tightly. The pull rod bolts achieve axial locking on each cylinder body section and play a role in positioning so as to ensure the radial and circumferential positions of each cylinder body section and ensure the concentricity of each section of the inner cylinder body.
In this way, the stay bolts of the inner cylinder body respectively lock the cylinder sections into a whole in the axial direction, forming a complete cylindrical inner cylinder without a split surface.
Of course, when the cylinder sections with the corresponding stationary blade assemblies are axially combined and connected, the assembly of the corresponding rotor assemblies should be performed synchronously, and in order to facilitate the assembly of the rotor assemblies in the inner cylinder body, the minimum inner diameter of each cylinder section should be slightly larger than the maximum outer diameter of the matched rotor assemblies, and the diameter difference should not affect the assembly of the inner cylinder body and the rotor assemblies.
In order to ensure circumferential symmetry of the inner cylinder structure, the bolt holes in the cylinder sections are preferably evenly distributed in the circumferential direction.
Example 5
The rest of the present embodiment is the same as that of embodiments 1, 2, 3 or 4, except that: the seal groove between adjacent cylinder sections is on one side-inside/outside of the bolt hole.
The above examples are intended to illustrate the invention, but not to limit it; although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that: the present invention may be modified from the embodiments described above or substituted for some of the technical features, and such modifications or substitutions do not depart from the spirit and scope of the present invention.
Claims (9)
1. The utility model provides a turbine inner cylinder structure, includes inner cylinder body, its characterized in that: the inner cylinder body is correspondingly divided into a plurality of cylinder sections (5) according to each stage of static blade assembly (7), or the inner cylinder body is correspondingly divided into a plurality of cylinder sections (5) according to each stage of static blade assembly (7) and the steam inlet chamber (3); the cylinder body is characterized in that a plurality of bolt holes are formed in the circumference of the wall thickness of each cylinder body section (5) of the inner cylinder body, the bolt holes in the circumference of each cylinder body section (5) are in one-to-one correspondence in the axial direction, the cylinder body sections (5) of the inner cylinder body are sequentially in butt joint in the axial direction, the bolt holes in the circumferential direction are made to correspond in the axial direction, a pull rod bolt (4) penetrates through each bolt hole in the axial direction, and the pull rod bolts (4) penetrating through the bolt holes in the axial direction respectively lock the cylinder body sections (5) into a whole in the axial direction to form the complete cylindrical inner cylinder.
2. The turbine inner cylinder structure according to claim 1, wherein: and the pull rod bolt (4) axially penetrates from a corresponding bolt hole on the steam exhaust side of the inner cylinder body and extends to the steam inlet side for locking.
3. The turbine inner cylinder structure according to claim 1 or 2, wherein: the butt joint face of the adjacent cylinder body section (5) of inner cylinder body upwards seted up mutual seal groove (8) that correspond, at the embedded sealing washer (6) that are equipped with of the seal groove (8) that correspond each other, sealing washer (6) keep off and seal on the axial butt joint face of adjacent cylinder body section (5).
4. The turbine inner cylinder structure according to claim 3, wherein: the sealing grooves (8) corresponding to each other on the butt joint surfaces of the adjacent cylinder sections (5) are two, and the two sealing grooves (8) are arranged on the inner side and the outer side of the bolt hole of the cylinder section (5).
5. The turbine inner cylinder structure according to claim 3, wherein: the sealing ring (6) is an L-shaped sealing ring folded inwards.
6. The turbine inner cylinder structure according to claim 1 or 2, wherein: the inner wall of cylinder section (5) is equipped with radial protruding spacing convex tooth (2) and adjustment convex tooth (14), spacing convex tooth (2) distribute in the left and right sides of horizontal position, correspond the well facet tip with quiet leaf subassembly (7) of the combination of horizontal well facet, adjustment convex tooth (14) distribute in the top bottom both sides of day position, correspond the top bottom portion with quiet leaf subassembly (7) of the combination of horizontal well facet, the periphery of quiet leaf subassembly (7) is equipped with the inlay groove that corresponds the convex tooth on cylinder section (5), the profile structure of the inlay groove on quiet leaf subassembly (7) is greater than the profile structure of the corresponding convex tooth on cylinder section (5).
7. The turbine inner cylinder structure according to claim 1 or 2, wherein: the outer end of the pull rod bolt (4) is connected with a spherical washer component (10) and a locking nut (11).
8. The turbine inner cylinder structure according to claim 1 or 2, wherein: the outer end in the pull rod bolt (4) is provided with a central hole (9) which is of an axial blind hole-shaped structure and can supply heat tightly.
9. The turbine inner cylinder structure according to claim 1, wherein: the minimum inner diameter (R2) of each cylinder section (5) of the inner cylinder body is larger than the maximum outer diameter (R1) of the matched rotor assembly (1).
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1158142A2 (en) * | 2000-05-20 | 2001-11-28 | General Electric Company | Reducing cracking adjacent shell flange connecting bolts |
| JP2005061273A (en) * | 2003-08-08 | 2005-03-10 | Ishikawajima Harima Heavy Ind Co Ltd | Gas turbine casing |
| CN102383879A (en) * | 2011-10-28 | 2012-03-21 | 上海电气电站设备有限公司 | Steam turbine structure |
| JP2013050044A (en) * | 2011-08-30 | 2013-03-14 | Toshiba Corp | Seal structure and steam turbine |
| CN206360732U (en) * | 2016-12-22 | 2017-07-28 | 东方电气集团东方汽轮机有限公司 | A kind of steam turbine cylindrical high voltage cylinder |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204627679U (en) * | 2015-03-26 | 2015-09-09 | 北京华清燃气轮机与煤气化联合循环工程技术有限公司 | A kind of turbine cylinder horizontal flange sealing configuration |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1158142A2 (en) * | 2000-05-20 | 2001-11-28 | General Electric Company | Reducing cracking adjacent shell flange connecting bolts |
| JP2005061273A (en) * | 2003-08-08 | 2005-03-10 | Ishikawajima Harima Heavy Ind Co Ltd | Gas turbine casing |
| JP2013050044A (en) * | 2011-08-30 | 2013-03-14 | Toshiba Corp | Seal structure and steam turbine |
| CN102383879A (en) * | 2011-10-28 | 2012-03-21 | 上海电气电站设备有限公司 | Steam turbine structure |
| CN206360732U (en) * | 2016-12-22 | 2017-07-28 | 东方电气集团东方汽轮机有限公司 | A kind of steam turbine cylindrical high voltage cylinder |
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