阅读说明：本技术 汽缸猫爪支撑结构、汽轮机及汽轮机稳定性校核方法 (Cylinder cat claw support structure, steam turbine and steam turbine stability checking method ) 是由 冯照和 马晓飞 王晓鹏 马利江 张军辉 陈�峰 罗敏 陈可轩 刘彩芳 陈华梅 于 2021-09-30 设计创作，主要内容包括：本申请涉及工业汽轮机设计技术领域,尤其是涉及一种汽缸猫爪支撑结构、汽轮机及汽轮机稳定性校核方法。该汽缸猫爪支撑结构包括猫爪、定距连接件和压紧组件；猫爪设置于汽缸的中分面处,猫爪通过定距连接件与汽缸连接；压紧组件可拆卸地设置于猫爪的背离于中分面的一侧,压紧组件能够以定距连接件为支点向中分面压紧猫爪。该汽轮机包括该汽轮机猫爪支撑结构。该汽轮机稳定性校核方法用于校核包括该汽缸猫爪支撑结构的汽轮机的稳定性。该汽缸猫爪支撑结构、汽轮机和该汽轮机稳定性校核方法,在设计阶段能够预防猫爪在出厂后偏离于中分面后无法恢复的情况发生,也能够预防汽轮机在使用过程中容易发生侧翻的情况发生。(The application relates to the technical field of industrial steam turbine design, in particular to a cylinder cat-claw supporting structure, a steam turbine and a steam turbine stability checking method. The cylinder cat-claw supporting structure comprises a cat claw, a distance connecting piece and a pressing assembly; the cat claw is arranged at the middle section of the cylinder and is connected with the cylinder through a fixed-distance connecting piece; compress tightly subassembly detachably and set up in one side that deviates from in the bisection face of cat claw, compress tightly the subassembly and can use the distance connecting piece to compress tightly the cat claw to the bisection face as the fulcrum. The steam turbine includes this steam turbine cat claw bearing structure. The steam turbine stability checking method is used for checking the stability of the steam turbine comprising the cylinder cat-claw supporting structure. The cylinder cat-claw supporting structure, the steam turbine and the steam turbine stability checking method can prevent the cat-claw from deviating from the middle split surface and being incapable of being recovered in a design stage, and can also prevent the steam turbine from being prone to side turning in a use process.)

1. A cylinder cat-claw supporting structure is characterized by comprising a cat claw, a distance connecting piece and a pressing assembly;

the cat claw is arranged at the middle split surface of the cylinder and is connected with the cylinder through the distance connecting piece;

the pressing assembly is used for being detachably arranged on one side, deviating from the middle parting surface, of the cat claw, and the pressing assembly can press the cat claw towards the middle parting surface by taking the distance connecting piece as a fulcrum.

2. The cylinder cat claw support structure according to claim 1, characterized in that the distance connecting piece is a distance bolt, the cat claw is provided with a connecting through hole, the distance bolt passes through the connecting through hole to be screwed with the cylinder, a circumferential space is formed between the distance bolt and the connecting through hole, and a nut of the distance bolt and a surface of the cat claw facing away from the bisecting plane form a predetermined space through a pressing assembly.

3. The cylinder cat claw support structure of claim 2 wherein the hold down assembly comprises two disc springs removably mounted to the distance bolt, the two disc springs being positioned between the nut of the distance bolt and the cat claw;

the dish springs are provided with a large-diameter end and a small-diameter end, the two dish springs are overlapped in a mode that the small-diameter ends are in butt joint, so that the large-diameter ends of the two dish springs are respectively abutted to the nut and the cat claw, or the two dish springs can be sequentially overlapped in a mode that the large-diameter ends face in the same direction, so that the two dish springs are separated from the nut.

4. The cylinder cat claw support structure of claim 3 further comprising a washer assembly comprising a first washer, a second washer and a third washer sleeved in sequence from the nut to the cat claw on the distance bolt;

an installation interval is formed between the inner ring of the second washer and the distance bolt, and the two disc springs are arranged in the installation interval;

the height of the single disc spring is not larger than that of the second washer, so that the first washer is in contact with the second washer and forms the predetermined interval with the nut under the condition that the two disc springs are sequentially overlapped in a manner that the large-diameter ends face in a consistent manner;

the sum of the heights of the two disc springs is greater than the height of the second washer so that the first washer abuts against the nut and forms the predetermined interval with the second washer in a state where the two disc springs are stacked with the small-diameter ends abutting.

5. The cylinder cat-claw support structure of claim 3 wherein the height of the predetermined gap and the maximum deflection of a single disc spring are each 0.1-0.2 mm;

the compression assembly provides a maximum tightening force to the cat's paw that is greater than the pipe effort.

6. A steam turbine comprising a cylinder and a cylinder catwalk support structure according to any one of claims 1 to 5.

7. A method for checking the stability of a steam turbine is characterized by comprising the following steps:

selecting an axis group comprising a first axis and a second axis which are not parallel to each other, wherein the planes of the first axis and the second axis are parallel to or coincident with the bisection plane;

calculating the load resultant moment of all the pipeline acting forces relative to the first axis as a first load resultant moment, and calculating the load resultant moment of all the pipeline acting forces relative to the second axis as a second load resultant moment;

calculating the resultant moment of the gravity of the steam turbine relative to the first axis as a first stability resultant moment, and calculating the resultant moment of the gravity of the steam turbine relative to the second axis as a second stability resultant moment;

comparing the first stability resultant moment with the first load resultant moment, and comparing the second stability resultant moment with the second load resultant moment;

and if the first stability resultant moment is greater than the first load resultant moment and the second stability resultant moment is greater than the second load resultant moment, the condition that the turbine cannot roll over is indicated.

8. The steam turbine stability verification method of claim 7, wherein a plurality of sets of the axes are selected, wherein the first and second axes in the plurality of sets of axes do not coincide with each other two by two;

and calculating and comparing the first stability resultant moment and the first load resultant moment and calculating and comparing the second stability resultant moment and the second load resultant moment by taking the first axis and the second axis of each axis group as rotating shafts.

9. The steam turbine stability verification method of claim 8, wherein two sets of said axis sets are selected;

a first axis of one of the sets of axes is selected to be parallel to a central axis of the turbine.

10. The steam turbine stability verification method of claim 7, further comprising the steps of:

comparing the resultant of all pipeline forces with the gravity of the turbine;

and if the resultant force of the acting forces of all the pipelines is smaller than the gravity of the steam turbine, the cylinder of the steam turbine cannot be jacked up.

Technical Field

The application relates to the technical field of industrial steam turbine design, in particular to a cylinder cat-claw supporting structure, a steam turbine and a steam turbine stability checking method.

Background

The steam turbine cylinder body is connected with a plurality of pipelines, wherein one pipeline is an inner pipeline, such as a balance pipe, an overflow pipe and the like, and the other pipeline is an outer pipeline, such as a new steam pipeline, a steam supplementing pipeline, a steam extraction pipeline, a steam exhaust pipeline and the like. Meanwhile, the self weight of the pipeline and the counter force of the bracket can also generate additional force and moment.

For a steam turbine cylinder body, such external force and external moment have great influence on the stability of the steam turbine cylinder body, for example, adverse conditions such as vibration of a cylinder and a pipeline and the like caused by blocking of jacking, side turning, translation and thermal expansion of the cylinder body are caused.

In order to ensure that the cylinder can expand freely after being heated, the supporting and positioning of the cylinder is the key in the unit design, and the cat-claw supporting structure is widely adopted at present to ensure that the steam turbine can be stably seated on a seat frame no matter in an installation state or an operation state, so that the steam turbine cylinder body is ensured to have better stability.

However, once the existing cat-claw support structure is installed before the cylinder leaves the factory, the structure of the cat-claw support structure cannot be adjusted, so that after the cylinder is installed on the seat frame through the cat-claw support structure after leaving the factory, the cat-claw support structure installed before leaving the factory may be subjected to a cylinder jacking situation due to the installation site or transportation, and the cat-claw support structure cannot be restored after deviating from the middle division plane.

Disclosure of Invention

The application aims to provide a cylinder cat-claw supporting structure, a steam turbine and a steam turbine stability checking method, and aims to solve the technical problem that the cat-claw supporting structure after leaving a factory in the prior art deviates from a split surface and cannot be restored to a certain extent.

The application provides a cylinder cat-claw supporting structure, which comprises a cat claw, a distance connecting piece and a pressing assembly;

the cat claw is arranged at the middle split surface of the cylinder through a distance connecting piece;

the pressing assembly is used for being detachably arranged on one side, deviating from the middle parting surface, of the cat claw, and the pressing assembly can press the cat claw towards the middle parting surface by taking the distance connecting piece as a fulcrum.

In above-mentioned technical scheme, furtherly, the distance connecting piece is the distance bolt, the cat claw is provided with connect the through-hole, the distance bolt passes connect the through-hole with the bisection face spiro union of cylinder, the distance bolt with form the circumference interval between the connect the through-hole, the nut of distance bolt with the cat claw deviate from in the surface of bisection face forms predetermined interval through compressing tightly the subassembly.

In any one of the above technical solutions, further, the pressing assembly includes two disc springs detachably sleeved on the distance bolt, and the two disc springs are located between a nut of the distance bolt and the cat claw;

the dish springs are provided with a large-diameter end and a small-diameter end, the two dish springs are overlapped in a mode that the small-diameter ends are in butt joint, so that the large-diameter ends of the two dish springs are respectively abutted to the nut and the cat claw, or the two dish springs can be sequentially overlapped in a mode that the large-diameter ends face in the same direction, so that the two dish springs are separated from the nut.

In any of the above technical solutions, further, the cylinder cat's claw support structure further includes a washer assembly, where the washer assembly includes a first washer, a second washer, and a third washer, which are sequentially sleeved on the distance bolt from the nut to the cat's claw;

an installation interval is formed between the inner ring of the second washer and the distance bolt, and the two disc springs are arranged in the installation interval;

the height of the single disc spring is not larger than that of the second washer, so that the first washer is in contact with the second washer and forms the predetermined interval with the nut under the condition that the two disc springs are sequentially overlapped in a manner that the large-diameter ends face in a consistent manner;

the sum of the heights of the two disc springs is greater than the height of the second washer so that the first washer abuts against the nut and forms the predetermined interval with the second washer in a state where the two disc springs are stacked with the small-diameter ends abutting.

In any of the above technical solutions, further, the height of the predetermined interval is 0.1-0.2 mm;

the compression assembly provides a maximum tightening force to the cat's paw that is greater than the pipe effort.

The application also provides a steam turbine, including cylinder and above-mentioned any technical scheme cylinder cat claw bearing structure.

The application also provides a method for checking the stability of the steam turbine, which comprises the following steps:

selecting an axis group comprising a first axis and a second axis which are not parallel to each other, wherein the planes of the first axis and the second axis are parallel to or coincident with the bisection plane;

calculating the load resultant moment of all the pipeline acting forces relative to the first axis as a first load resultant moment, and calculating the load resultant moment of all the pipeline acting forces relative to the second axis as a second load resultant moment;

calculating the resultant moment of the gravity of the steam turbine relative to the first axis as a first stability resultant moment, and calculating the resultant moment of the gravity of the steam turbine relative to the second axis as a second stability resultant moment;

comparing the first stability resultant moment with the first load resultant moment, and comparing the second stability resultant moment with the second load resultant moment;

and if the first stability resultant moment is greater than the first load resultant moment and the second stability resultant moment is greater than the second load resultant moment, the condition that the turbine cannot roll over is indicated.

In any of the above technical solutions, further, a plurality of groups of the axis groups are selected, and the first axis and the second axis in the plurality of groups of the axis groups are not overlapped with each other two by two;

and calculating and comparing the first stability resultant moment and the first load resultant moment and calculating and comparing the second stability resultant moment and the second load resultant moment by taking the first axis and the second axis of each axis group as rotating shafts.

In any of the above technical solutions, further, two sets of the axis groups are selected;

a first axis of one of the sets of axes is selected to be parallel to a central axis of the turbine.

In any of the above technical solutions, further, the method for checking the stability of the steam turbine further includes the following steps:

comparing the resultant of all pipeline forces with the gravity of the turbine;

and if the resultant force of the acting forces of all the pipelines is not greater than the gravity of the steam turbine, the fact that the cylinder of the steam turbine cannot be jacked up is indicated.

Compared with the prior art, the beneficial effect of this application is:

the application provides a cylinder cat claw bearing structure includes cat claw, distance connecting piece and compresses tightly the subassembly. The cat claw sets up in the mid-plane department of cylinder, and the cat claw passes through the distance connecting piece and is connected with the cylinder to make the cylinder pass through the cat claw and stably sit on the seat frame. Compress tightly subassembly detachably and set up in one side that deviates from in the well minute face of cat claw, the cat claw breaks away from under the condition of well minute face owing to reasons such as installation scene or transportation, uses the distance connecting piece as the fulcrum to compress tightly the cat claw to well minute face through compressing tightly the subassembly to make the cat claw resume to the state with well minute face laminating. This cylinder cat claw bearing structure can correct the cat claw that deviates from in the well facet at the installation stage of cylinder to avoid because the cat claw deviates from the well facet and leads to the condition emergence that the cylinder scrapped or returned the factory, and then be favorable to reducing the cylinder disability rate and returning the factory rate, and improve the installation effectiveness of cylinder.

The application provides a steam turbine, including foretell cylinder cat claw bearing structure, therefore can stably be located in the seat frame through this cylinder cat claw bearing structure to can realize this cylinder cat claw bearing structure's all beneficial effects.

According to the steam turbine stability checking method, stability of the cylinder is checked by comparing the stability resultant moment and the load resultant moment. The cylinder is taken as a whole to be subjected to stability analysis instead of being checked from a single pipe orifice, compared with the existing NEMASM23 checking method, the checking limitation is obviously reduced, and the risk is mainly embodied in the mode that the cylinder overturns after the cylinder is located on a seat frame through a cat claw, so that whether the cylinder overturns can be effectively verified through the checking method, the practicability of a checking result is improved, particularly for a unit with a small model, the checking from the single pipe orifice is unreliable due to the small dead weight, and the unit can be effectively prevented from being overturned through the checking method.

After the steam turbine stability checking method is used for checking, the situation that external equipment such as pipelines and the like are rearranged and adjusted due to poor stability of the unit when the unit runs in future can be avoided, and a large amount of manpower and material resources generated due to reworking and maintenance are saved. The method for checking the stability of the steam turbine is verified on hundreds of steam turbines, and is proved to be reasonable and reliable through years of operation feedback.

Drawings

In order to more clearly illustrate the detailed description of the present application or the technical solutions in the prior art, the drawings needed to be used in the detailed description of the present application or the prior art description will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic structural view of a cylinder catclaw support structure according to an embodiment of the present disclosure;

FIG. 2 is an enlarged partial view of a compression assembly of a cylinder catclaw support structure in a first state as provided in one embodiment of the present application;

FIG. 3 is an enlarged partial view of a compression assembly of a cylinder catclaw support structure in a second state as provided in one embodiment of the present application;

fig. 4 is a force analysis diagram of a second cylinder stability checking method according to an embodiment of the present application.

Reference numerals:

1-a cylinder; 10-split of the flour; 11-central axis; 2-cat's claw; 3-a pressing component; 30-a disc spring; 4-a gasket assembly; 40-a first gasket; 41-a second gasket; 42-a third gasket; 5-a predetermined interval; 6-distance connecting pieces; 7-circumferential spacing; 8-installation interval; 9-a first axis group; 90-a first axis of the first set of axes; 91-a second axis of the first set of axes; 12-second axis group; 120-a first axis of a second axis group; 121-second axis of the second axis group.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example one

Referring to figures 1 to 4, embodiments of the present application provide a cylinder cat claw support structure comprising a cat claw 2, a distance connector 6 and a compression assembly 3.

The cylinder 1 comprises a lower cylinder and an upper cylinder, the middle section 10 of the cylinder 1 is the surface of the upper cylinder and the lower cylinder of the cylinder 1 which are butted, and the cat claw 2 is arranged on the middle section 10 of the cylinder 1 through a distance connecting piece, so that the cylinder 1 can be ensured to be stably seated on a seat frame. Wherein, usually the cat's claw 2 and the last jar of cylinder 1 integrated into one piece, well facet 10 forms the top at the lower jar of cylinder 1, and when the condition that the upper jar was jacked for well facet 10 appears, commonly known as takes place the top of the jar condition, cat's claw 2 was jacked simultaneously along with the upper jar, therefore can influence the stability of cylinder 1 installation on the frame.

Compress tightly subassembly 3 detachably and set up in one side that deviates from in well minute face 10 of cat claw 2, compress tightly subassembly 3 and can use distance connecting piece 6 to compress tightly cat claw 2 to well minute face 10 as the fulcrum, in other words, compress tightly subassembly 3 and have first state and second state, under first state, compress tightly subassembly 3 and use distance connecting piece 6 to compress tightly cat claw 2 to well minute face 10 as the fulcrum, under the second state, compress tightly subassembly 3 and do not exert pressure to cat claw 2, cat claw 2 can make cat claw 2 fix at well minute face 10 through the fixed action of distance connecting piece 6. Thus after seating the cylinder 1 on the mount via the cat's claw 2, the positional relationship between the cat's claw 2 and the midplane 10 is checked, and the hold down assembly 3 is adjusted to the first state if the cat's claw 2 is disengaged from the midplane 10, and the hold down assembly 3 is held in the second state if the cat's claw 2 remains at the midplane 10.

In this embodiment, once the assembly position between the middle section of the cylinder 1 and the cat's claw 2 is adjusted by the pressing component 3, the pressing component 3 cannot be removed, so as to ensure that the cat's claw 2 is maintained in a state of being attached to the middle section 10. It is therefore necessary to ensure that the maximum tightening force provided by the compression assembly 3 to the cat's claw 2 is greater than the pipe action force to ensure that the compression assembly 3 does not fail under the action of the pipe action force in the use of the cylinder 1, thereby effectively avoiding the cat's claw 2 disengaging from the median plane 10 and causing irreversible influence on the stability of the cylinder 1.

In the alternative of this embodiment, distance connecting piece 6 is the distance bolt, and cat claw 2 is provided with connect the through-hole, and the distance bolt passes connect the through-hole and the well minute face spiro union of cylinder, forms circumference interval 7 between distance bolt and the connect the through-hole, and the nut of distance bolt and cat claw 2 deviate from the surface in well minute face 10 and form predetermined interval 5 through compressing tightly subassembly 3. Specifically, a predetermined gap is formed between the distance bolt and the hold-down assembly 3, or a predetermined gap is formed inside the hold-down assembly 3, as long as the nut of the distance bolt and the hold-down assembly 3 can be prevented from coming into close contact with the cat's claw 2 together.

Thereby in the use of this cylinder 1, if cylinder 1 produces the inflation because of generating heat, owing to be provided with predetermined clearance, distance bolt and compress tightly subassembly 3 and do not compress tightly cat claw 2 and cylinder 1 completely, and form circumference interval 7 between distance bolt and the inner wall of connect the through-hole, so the distance bolt can be under the drive of cylinder 1 horizontal migration in the connect the through-hole to satisfy the removal demand of cylinder 1 under the inflation effect, form rigid connection through avoiding cat claw 2 and cylinder 1, thereby avoid cylinder 1 because can not expand freely and take place serious deformation.

In the alternative of this embodiment, hold-down assembly 3 includes two dish springs 30 that detachably cover was located the distance bolt, and two dish springs 30 are located between the nut of distance bolt and cat claw 2.

The disc springs 30 have a large diameter end and a small diameter end, and in the first state of the pressing assembly 3, the two disc springs 30 are stacked in a manner that the small diameter ends are butted, so that the large diameter ends of the two disc springs 30 are butted with the nut and the cat claw 2 respectively, and in this state, the supporting force provided by the two disc springs 30 is still the supporting force provided by the single disc spring 30, and only the height is enough to enable the large diameter ends of the two disc springs 30 to be butted with the nut and the cat claw 2 respectively.

Thereby two dish springs 30 use the nut to exert the holding power towards well minute face 10 to cat claw 2 as the fulcrum, and then be not more than the holding power that single dish spring 30 provided when the pipeline effort, can make cat claw 2 keep in well minute face 10 to guarantee cylinder 1 stability.

Or, in the second state, the two disc springs 30 can be sequentially overlapped in a manner that the large-diameter ends face towards the same direction, so that the two disc springs 30 are separated from the nut, and no additional spring force is generated, so that before the cylinder 1 leaves the factory, the two disc springs 30 are overlapped in this state, and not only can the two disc springs 30 leave the factory along with the cylinder 1 synchronously for subsequent position adjustment of the cat-paw 2, but also the two disc springs 30 do not affect the normal connection between the cat-paw 2 and the cylinder 1 if the cat-paw 2 does not need to be adjusted subsequently.

In this embodiment, the cylinder cat-claw support structure further comprises a washer assembly 4, the washer assembly 4 comprising a first washer 40, a second washer 41 and a third washer 42 that are sleeved onto the distance bolt from the nut to the cat-claw 2 in sequence.

An installation space 8 is formed between the inner ring of the second washer 41 and the distance bolt, the two disc springs 30 are arranged in the installation space 8, and an installation space is provided for the disc springs 30 through the installation space 8, so that the two disc springs 30 are located between the first washer 40 and the second washer 41 along the axial direction of the distance bolt, the bottom ends of the disc springs 30 are located on the third washer 42 all the time, and the top ends of the disc springs 30 face the first washer 40.

The height of the single disc spring 30 is not greater than that of the second washer 41 so that in the case where the two disc springs 30 are sequentially stacked with the large-diameter ends facing uniformly, that is, in the second state, the tops of the two disc springs 30 are not in contact with the first washer 40, that is, do not jack up the first washer 40, and the first washer 40 forms a predetermined interval 5 with the nut to prevent the cat's claw 2 from forming a rigid connection with the upper cylinder of the cylinder 1, thereby ensuring that the cylinder 1 has a sufficient expansion margin.

The sum of the heights of the two disc springs 30 is greater than the height of the second washer 41, and in the case where the two disc springs 30 are stacked with the small-diameter ends in abutment, that is, in the first state, the tops of the two disc springs 30 are in contact with the first washer 40 and jack the first washer 40 up to a position in abutment with the nut, and at the same time, a predetermined space 5 is formed between the first washer 40 and the second washer 41 to prevent the cat's claw 2 from being rigidly connected to the lower cylinder of the cylinder 1, thereby ensuring a sufficient expansion margin of the lower or upper cylinder of the cylinder 1.

In the present embodiment, generally speaking, the moving distance of the cylinder 1 in the height direction caused by the heat expansion driving the cat's claw 2 is 0.1-0.2mm, and the thermal expansion requirement of the cat's claw 2 can be satisfied by setting the height of the predetermined interval 5 and the maximum deformation amount of the single disc spring 30 to 0.1-0.2 mm. For example, the height of the predetermined gap 5 and the maximum deformation amount of the individual disc spring 30 are each 0.1mm, 0.12mm, 0.15mm, 0.18mm, or 0.2 mm.

Example two

The second embodiment provides a steam turbine which is used for checking the steam turbine with the cylinder cat-foot support structure in the first embodiment, the technical characteristics of the cylinder cat-foot support structure disclosed in the first embodiment are also applicable to the second embodiment, and the technical characteristics of the cylinder cat-foot support structure disclosed in the second embodiment are not repeated.

The steam turbine provided by the embodiment comprises the cylinder 1 and the cylinder cat-claw supporting structure provided by the embodiment I. Specifically, the number of the dogs 2 may be four, and the four dogs 2 are disposed two by two symmetrically with respect to the central axis 11 of the cylinder 1, wherein the central axis 11 of the cylinder 1 is a central line in the left-right direction of the cylinder 1 and extends in the front-rear direction of the cylinder 1.

The steam turbine stability checking method in the embodiment has the advantages of the cylinder 1 and the cat-claw 2 supporting structure in the first embodiment, and the advantages of the cylinder cat-claw supporting structure disclosed in the first embodiment are not described repeatedly.

EXAMPLE III

The third embodiment provides a method for checking the stability of the steam turbine, the third embodiment is used for checking the steam turbine in the second embodiment, the technical characteristics of the steam turbine disclosed in the second embodiment are also applicable to the third embodiment, and the technical characteristics of the steam turbine disclosed in the second embodiment are not described repeatedly.

Referring to fig. 4 in combination with fig. 1 to fig. 3, the method for checking the stability of the steam turbine according to this embodiment includes the following steps:

s100, selecting an axis group comprising a first axis and a second axis which are not parallel to each other, wherein the plane where the first axis and the second axis are located is parallel to or coincident with the median plane 10;

step S200, calculating the load resultant moment of all the pipeline acting forces relative to a first axis as a first load resultant moment, and calculating the load resultant moment of all the pipeline acting forces relative to a second axis as a second load resultant moment;

step S300, calculating a resultant moment of the gravity of the steam turbine relative to a first axis as a first stability resultant moment, and calculating a resultant moment of the gravity of the steam turbine relative to a second axis as a second stability resultant moment;

step S400, comparing the first stability resultant moment with the first load resultant moment, and comparing the second stability resultant moment with the second load resultant moment;

step S500, if the first stability resultant moment is greater than the first load resultant moment and the second stability resultant moment is greater than the second load resultant moment, it indicates that the cylinder 1 meets the stability checking requirement.

In this embodiment, in step S100, the first axis and the second axis may both be located in the bisector 10, or both may be parallel to the bisector 10, and the first axis and the second axis are not parallel to each other, so as to determine a two-dimensional coordinate system parallel to or coincident with the bisector 10, and optionally, the first axis and the second axis are perpendicular to each other.

In step S200, the negative effect of all the pipe forces on the stability of the cylinder 1 is quantified globally by calculating the first and second resultant load moments. Wherein, every pipeline effort is the design institute and provides, need not to gather and can use, and it is convenient to calculate.

In step S300, the positive effect of the gravity of the turbine on the stability of the cylinder 1 is quantified globally by calculating the first and second resultant moments of stability. Wherein, the gravity of steam turbine provides for the design institute, need not to gather and can use, and it is convenient to calculate.

In step S400, it is determined whether the cylinder is likely to roll over about the first axis by comparing the negative effects with the positive effects along the first axis, and whether the cylinder is likely to roll over about the second axis by comparing the negative effects with the positive effects along the second axis, which largely indicates that the cylinder is not likely to roll over relative to the midplane 10 if neither the cylinder is likely to roll over about the first axis nor the cylinder is likely to roll over about the second axis.

It is worth emphasizing that, in the comparison process, if the direction of the first resultant load moment is the same as that of the first resultant stability moment, or the direction of the first resultant load moment is different from that of the first resultant stability moment, but the first resultant load moment is smaller than that of the first resultant stability moment, it indicates that the rollover effect of all the pipe acting forces on the first axis is within the allowable range. Similarly, if the direction of the second resultant load moment is the same as that of the second resultant stability moment, or the direction of the second resultant load moment is different from that of the second resultant stability moment, but the second resultant load moment is smaller than that of the second resultant stability moment, it indicates that the side-rolling action generated by all the pipeline acting forces about the second axis is within the allowable range.

Furthermore, the checking method for the stability of the steam turbine is considered on the whole, the directionality of force and moment is considered, and the influence of the directionality on the whole cannot be reflected when the checking method is used for checking a single nozzle, so that the checking method is simple, feasible, reliable and comprehensive.

In an alternative of this embodiment, a plurality of sets of axis groups are selected, and the first axes and the second axes in the plurality of sets of axis groups are not overlapped with each other two by two, that is, the first axes in all the sets of axis groups are not overlapped, and the second axes in all the sets of axis groups are not overlapped.

And calculating and comparing a first stability resultant moment and a first load resultant moment and calculating and comparing a second stability resultant moment and a second load resultant moment by taking the first axis and the second axis of each axis group as rotating shafts. Therefore, whether the turbine turns over around the first axes or not can be checked, whether the turbine turns over around the second axes or not can be checked, and the possibility that the turbine turns over can be eliminated in space more comprehensively.

In this embodiment, in order to balance between the calculation simplification requirement and the diversity of the calculation dimensions, two sets of axis groups are selected. As shown in fig. 4, an arrangement of the first axis 90 of the first axis group and the second axis 91 of the first axis group is shown, and an arrangement of the first axis 120 of the second axis group and the second axis 121 of the second axis group is shown.

In the present embodiment, the first axis of one of the plurality of sets of axes is selected to be parallel to the central axis 11 of the cylinder 1, in order to simplify the calculation. In addition, the area of the steam turbine covered by the multiple groups of shaft groups can be increased, and the discrete degree of the positions of different shaft groups can be increased to improve the reliability of checking.

In an alternative of this embodiment, the method for checking the stability of the steam turbine further includes the following steps:

step S500, comparing the resultant force of all pipeline acting forces with the gravity of the steam turbine;

and step S600, if the resultant force of the acting forces of all the pipelines is not greater than the gravity of the steam turbine, the steam turbine cannot be jacked up.

When the gravity of the steam turbine is large enough, the pressure of the steam turbine on the seat frame is large enough, and the problems of jacking, translation and the like cannot occur, so that after the steam turbine is checked through the step S500 and the step S600, the steam turbine can be prevented from jacking and translating after leaving a factory. Particularly, in the case of a steam turbine with a small size, the problems of jacking and translation are very likely to occur, and thus the checking in step S500 and step S600 is necessary.

It is to be emphasized that, in the comparison process of step S600, if the direction of resultant of the pipe acting force is the same as the direction of gravity of the turbine or the direction of resultant of the pipe acting force is opposite to the direction of gravity of the turbine but the magnitude of the pipe acting force is smaller than the magnitude of gravity of the turbine, the resultant of the pipe acting force is within the allowable range.

The method for checking the stability of the steam turbine in the embodiment has the advantages of the steam turbine in the second embodiment, and the advantages of the steam turbine disclosed in the second embodiment are not described repeatedly herein.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention. Furthermore, those skilled in the art will appreciate that while some embodiments herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.