CN202170816U - Steam sealing system of steam power device - Google Patents
Steam sealing system of steam power device Download PDFInfo
- Publication number
- CN202170816U CN202170816U CN2011202407620U CN201120240762U CN202170816U CN 202170816 U CN202170816 U CN 202170816U CN 2011202407620 U CN2011202407620 U CN 2011202407620U CN 201120240762 U CN201120240762 U CN 201120240762U CN 202170816 U CN202170816 U CN 202170816U
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- steam
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- power plant
- labyrinth
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Abstract
The utility model discloses a steam sealing system of a steam power device, belonging to the technical field of steam power devices. The steam sealing system of the steam power device comprises steam sealing bodies, wherein the steam sealing bodies are arranged between a cylinder body of a steam turbine and a rotor, radial gaps are arranged between the cylinder body and the steam sealing bodies, sealing rings are arranged between the cylinder body and the steam sealing bodies, annular grooves are formed on the cylinder body in the radial direction, annular grooves are formed on the steam sealing bodies along the axial direction, and the sealing rings are arranged in the grooves of the cylinder body and the grooves of the steam sealing bodies in a constraint manner. With the adoption of the structure, the steam sealing bodies can be prevented from being damaged during expansion to affect steam sealing and cause steam leakage, and bearings near the steam sealing bodies are prevented from being rusted by steam, and the safety of equipment is improved.
Description
Technical field
The utility model relates to steam power plant, relates in particular to the sealing system of steam power plant.
Background technique
In steam power plant; Be generally steam turbine, need to guarantee the normal operation of machine, shaft end gland seal, diaphragm gland and shroud packing are arranged usually through various sealing glands; The effect of shaft end gland seal is for preventing the two axial ends gas leakage of rotor; Diaphragm gland and shroud packing mainly are to prevent inter-stage gas leakage, and in the traditional design, the labyrinth casing in the shaft end gland seal is fixed in the hollow nest of cylinder body; The outer circumferential face of labyrinth casing abuts against with the inwall of cylinder body, can produce following shortcoming when causing the labyrinth casing expanded by heating:
(1) labyrinth casing is heated earlier, and outwards expansion can receive the restriction of cylinder body, and then swell value is inevitable inwardly discharges; Cause its Internal Hole Deformation easily, changed the labyrinth clearance, gland sealing gear and rotor are easy to generate collision; And produce gas leakage, axle head leaks gas except that meeting makes heat energy loss, because of its near the antero posterior axis bearing; The gas leakage meeting shows slightly negative pressure because of attach wall phenomenon and the front end bearing support of steam because of the high speed rotating of rotor, in case gas leakage will get into bearing support because of above reason, long-time moisture meeting makes oily emulsification in the lubricant oil; Except that the inherent characteristic that influences steam turbine oil; Also possibly cause the corrosion of vitals such as guiding valve, oil engine, and cause bite, reduce the Economy and the Security of unit;
(2) can cause in the generation of cylinder body split after labyrinth casing expands and dehisce, thereby cause gas leakage herein;
The main effect of diaphragm gland is to be used for hindering steam to walk around the energy loss that nozzle causes, and the radial thrust on the impeller is increased, and reduces air leakage; Guarantee the efficient of steam power plant; But under the form of traditional packing, along with the time lengthening that unit comes into operation, the gland sealing gear of the labyrinth ring of installing on the dividing plate and the frictional loss between the rotor and distortion meeting increase gradually; And there is axial clearance between dividing plate and impeller and the blade; So just cause air leakage constantly to increase, the gap between dividing plate and impeller and the blade can make the steam that flows out from the dividing plate nozzle in the gap, spread; Reduce the utilization efficiency of steam, this also becomes influences the insurmountable for a long time difficult problem of of steam power plant efficient;
The shroud packing mainly be to be used for preventing that steam from walking around the energy loss that vane tip causes, in traditional design, shroud and with labyrinth ring that it matches between mainly adopt flat tooth packing, be easier to impairedly, cause air leakage bigger.
Summary of the invention
The utility model technical problem to be solved is: a kind of sealing system of steam power plant is provided, and it can effectively reduce the leakage of steam, improves the efficient and the working life of steam power plant.
For solving the problems of the technologies described above; The technological scheme of the utility model is: a kind of sealing system of steam power plant, comprise the cylinder body that is arranged at steam turbine and the labyrinth casing between the rotor, and be provided with radial clearance between said cylinder body and the labyrinth casing; Be provided with seal ring between said cylinder body and the labyrinth casing; Be provided with annular groove in the radial direction on the said cylinder body, said labyrinth casing is provided with annular groove in axial direction, and the constraint of said seal ring is installed in the groove of groove and labyrinth casing of said cylinder body.
As a kind of improvement, be provided with exhaust cavity between said labyrinth casing and the cylinder body, said labyrinth casing is provided with the exhaust port that is used for the discharge of the steam between said rotor and the labyrinth casing, and said exhaust port is communicated with said exhaust cavity; Said cylinder body is provided with bleeder hole, and said bleeder hole is communicated with exhaust cavity.
As a kind of improvement, said seal ring is arranged on the sidewall of said exhaust cavity.
As a kind of improvement, the sealing system of said steam power plant also comprises the refluence ring of the end blade outlet steam flow downstream labyrinth casing that is used to limit said rotor, and said refluence ring is fixedly installed on the said labyrinth casing.
As a kind of improvement, the sealing system of said steam power plant also comprises the dividing plate that is arranged in the said cylinder body and the packing parts between the said epitrochanterian blade.
As a kind of improvement, said dividing plate is provided with groove, and said blade is provided with the protruding back-up ring that the groove with said dividing plate is complementary, and said packing parts are arranged between the groove and said protruding back-up ring of said dividing plate.
As a kind of improvement, said packing parts comprise first labyrinth ring, and an opening end of said first labyrinth ring is flush-mounted on the groove of said dividing plate, and another opening end of said first labyrinth ring extends to said protruding back-up ring.
As a kind of improvement, the sealing system of said steam power plant also comprises the shroud on the blade that is fixedly installed in said rotor and forms second labyrinth ring of Honeycomb steam seal around said shroud and with said shroud.
As a kind of improvement, the sealing system of said steam power plant comprises also and being used for the lead guide ring of said dividing plate nozzle of said epitrochanterian velocity stage blade outlet steam that said guide ring is fixedly installed on the said cylinder body.
Owing to adopted technique scheme, the beneficial effect of the utility model is:
Because be provided with radial clearance between said cylinder body and the labyrinth casing, and be provided with seal ring between cylinder body and the labyrinth casing, seal ring can prevent that steam from leaking between labyrinth casing and cylinder body; Seal ring constraint is installed in the groove of labyrinth casing and cylinder body, can make seal ring not only in groove, seal but also the clearance for expansion is arranged, so the space of free expansion is arranged during the labyrinth casing expanded by heating; Not can and cylinder body between interaction force takes place, thereby the swell value that can prevent labyrinth casing inwardly discharges, the extruding that causes the endoporus of labyrinth casing to receive makes Internal Hole Deformation; Prevent the gland sealing gear and the rotor damaged in collision of labyrinth ring; Cause sealing effect bad, cause gas leakage, also prevent that the expansion of labyrinth casing from producing an outside tension force to cylinder body simultaneously; Cause the gas leakage of dehiscing in producing of the split of cylinder body; So just reduce the leakage of steam, improved the utilization ratio of steam, thereby improved the efficient of steam power plant; Preventing that steam from leaking also plays a protective role near antero posterior axis bearing, and increased the working life of front and back bearings.
Can the steam between rotor and the labyrinth casing be extracted out through exhaust port; Can on the bleeder hole of cylinder body, connect vapor extractor and draw gas condenser; The steam of extracting out is become condensed water to be sent into thermodynamic system and utilizes again; Both can guarantee the packing effect between rotor and the labyrinth casing, can also economize on resources.
The ring that flows backwards can prevent the steam flow labyrinth casing, prevents that the impact force of steam is bigger than the load of ambassador's labyrinth casing, damages labyrinth casing, and it is excessive also to prevent that labyrinth casing from expanding simultaneously, influences the packing effect.
Owing to be provided with the packing parts between dividing plate and the said epitrochanterian blade; The space of nozzle between dividing plate and rotor that can stop steam to walk around dividing plate through the packing parts flows into the blade; Cause the heat energy loss of steam, so just solved the labyrinth ring and the growth of rotor on dividing plate, installed with service time, between the two each other wearing and tearing cause the sealing reduction; The inter-stage air leakage increases, thus the problem that causes steam power plant efficient to reduce; And, reduce the utilization ratio of steam because the steam that comes out from the dividing plate nozzle will diffuse to the space between dividing plate and the blade, can reduce the space of diffusion of vapor through the packing parts; Play the effect of throttling shrinkage cavity, improve the utilization ratio of steam, because the inter-stage air leakage significantly reduces; Therefore stage head is little; End thrust is little, and thrust-bearing load is little, and unit operation is safe.
Because diaphragm gland comprises the packing parts that are installed on said dividing plate middle part; Said packing parts and said blade are oppositely arranged; Can improve the effect of diaphragm gland, in the time of can reducing at the sealing effect of the labyrinth ring on rotor and the dividing plate, prevent that steam from spilling between rotor and labyrinth ring; Simultaneously prevent that also steam from going to the space between dividing plate and the blade from the nozzle leakage of dividing plate; Be equivalent to all play at each grade the effect of a shrinkage cavity throttling, air leakage can reduce step by step, and Efficiency of Steam Turbine also can correspondingly improve.
Because dividing plate is provided with groove; Said blade is provided with protruding back-up ring; Said packing parts are arranged between the groove and said protruding back-up ring of said dividing plate, and groove through dividing plate and protruding back-up ring cooperate can make sealing effect better, also makes the installation of packing parts comparatively convenient simultaneously.
Because the packing parts comprise first labyrinth ring on the groove that is flush-mounted in said dividing plate, first labyrinth ring is simple in structure, and is easy to manufacture, and installation is also comparatively convenient.
Because adopt Honeycomb steam seal between shroud and said second labyrinth ring, the packing effect is better, long service life.
Because also comprising, the sealing system of said steam power plant is used for the lead guide ring of said dividing plate nozzle of said epitrochanterian velocity stage blade outlet steam; Therefore can make steam from velocity stage blade, flow out the nozzle that the back accurately gets into dividing plate; Reduce the loss of energy, improve the utilization ratio of steam.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the utility model is further specified.
Fig. 1 is the whole structure sectional view of the utility model embodiment;
Fig. 2 is the structural representation of the utility model embodiment's labyrinth casing;
Fig. 3 is the utility model embodiment's the dividing plate and the user mode schematic representation of rotor;
Fig. 4 is the enlarged view at A place among Fig. 1 of the utility model embodiment;
Among the figure: 1, seal ring; 2, labyrinth casing; 21, exhaust port; 3, cylinder body; 4, rotor; 5, nozzle sets; 6, the second labyrinth rings; 7, blade; 8, guide ring; 9, dividing plate; 10, flange; 11, ring flows backwards; 12, the first labyrinth rings; 13, protruding back-up ring.
Embodiment
Shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4 were common, a kind of sealing system of steam power plant comprised the cylinder body 3 that is arranged at steam turbine and the labyrinth casing 2 between the rotor 4; Between said labyrinth casing 2 and the rotor 4 labyrinth ring is installed; Adopt the broach labyrinth gland between said labyrinth ring and the said rotor 4, be provided with radial clearance between said cylinder body 3 and the labyrinth casing 2, be provided with seal ring 1 between said cylinder body 3 and the labyrinth casing 2; Be provided with annular groove in the radial direction on the said cylinder body 3; Said labyrinth casing 2 is provided with annular groove in axial direction, 1 constraint of said seal ring is installed in the groove of groove and labyrinth casing 2 of said cylinder body 3, can play seal action in order to make seal ring 1; Do not influence the expansion of labyrinth casing 2 again; One end face of said seal ring 1 leans on the groove inwall of said cylinder body 3, is provided with axial clearance between the groove inwall of other end and said cylinder body 3, is provided with radial clearance between the groove inwall of said seal ring 1 and said cylinder body 3; Said seal ring 1 abuts in together with the two side of the groove of said labyrinth casing 2 mutually, is provided with axial clearance between said seal ring 1 and the said labyrinth casing 2.
Be provided with exhaust cavity between said labyrinth casing 2 and the cylinder body 3, said labyrinth casing 2 is provided with the exhaust port 21 that is used for the discharge of the steam between said rotor 4 and the labyrinth casing 2, and said exhaust port 21 is communicated with said exhaust cavity; Said cylinder body 3 is provided with bleeder hole, and said bleeder hole is communicated with exhaust cavity, and said bleeder hole is connected with the condenser that draws gas with vapor extractor, and the said condenser that draws gas is sent condensed condensed water into thermodynamic system and utilized again, has saved resource.
Said seal ring 1 is arranged on the sidewall of said exhaust cavity, and for easy for installation, said seal ring 1 is made up of two seal ring halfbodies usually.
The sealing system of said steam power plant also comprises the refluence ring 11 of the end blade 7 outlet steam flow downstream labyrinth casings 2 that are used to limit said rotor 4, and said refluence ring 11 is fixedly installed on the said labyrinth casing 2.
The sealing system of said steam power plant also comprises the dividing plate 9 that is arranged in the said cylinder body 3 and the packing parts between the blade 7 on the said rotor 4; Said dividing plate 9 is provided with groove; Said blade 7 is provided with the protruding back-up ring 13 that the groove with said dividing plate 9 is complementary; The protruding back-up ring 13 of prime number stretches in the groove of said dividing plate 9; Said packing parts are arranged between the groove and said protruding back-up ring 13 of said dividing plate 9, and said packing parts comprise first labyrinth ring 12, and an opening end of said first labyrinth ring 12 is flush-mounted on the groove of said dividing plate 9; Another opening end of said first labyrinth ring 12 extends to said protruding back-up ring 13; Have the gap between first labyrinth ring 12 and the said protruding back-up ring 13, the plane radially of the anchor ring of said first labyrinth ring 12 and dividing plate 9 is 45, and said first labyrinth ring 12 adopts selects for use the stainless steel sheets of high temperature high voltage resistant to process.
The sealing system of said steam power plant also comprises the shroud on the blade 7 that is fixedly installed in said rotor 4 and forms second labyrinth ring 6 of Honeycomb steam seal around said shroud and with said shroud; Because velocity stage blade 7 that matches with nozzle sets 5 and blade 7 apart from each others that match with dividing plate 9; In order to reduce the energy loss of steam; The sealing system of said steam power plant also comprises and being used for the lead guide ring 8 of said dividing plate 9 nozzles of the velocity stage blade on the said rotor 47 outlet steam; Said guide ring 8 is fixedly installed on the said cylinder body 3; Said dividing plate 9 is provided with the flange 10 in the wound impeller outside, and said second labyrinth ring 6 is installed in respectively on the flange 10 of guide ring 8 and dividing plate 9.
Adopt after the said structure, gas leakage of the axle head of steam power plant and inter-stage gas leakage all significantly reduce, and can improve the efficient of steam power plant greatly; Efficient than like product can improve about 20%, and economic benefit is very considerable, and axle head gas leakage reduces position corrosions such as can preventing bearing; The life-span of raising equipment, also improved the Security that equipment uses, inter-stage leaks gas, and stage head is little at least; End thrust is little, thereby has improved the Security of unit operation.
The utility model is not limited to above-mentioned concrete mode of execution, and those of ordinary skill in the art is from above-mentioned design, and without performing creative labour, all conversion of having done all drop within the protection domain of the utility model.
Claims (9)
1. the sealing system of steam power plant; Comprise the cylinder body that is arranged at steam turbine and the labyrinth casing between the rotor; It is characterized in that: be provided with radial clearance between said cylinder body and the labyrinth casing, be provided with seal ring between said cylinder body and the labyrinth casing, be provided with annular groove in the radial direction on the said cylinder body; Said labyrinth casing is provided with annular groove in axial direction, the constraint of said seal ring is installed in the groove of groove and labyrinth casing of said cylinder body.
2. the sealing system of steam power plant as claimed in claim 1; It is characterized in that: be provided with exhaust cavity between said labyrinth casing and the cylinder body; Said labyrinth casing is provided with the exhaust port that is used for the discharge of the steam between said rotor and the labyrinth casing, and said exhaust port is communicated with said exhaust cavity; Said cylinder body is provided with bleeder hole, and said bleeder hole is communicated with exhaust cavity.
3. the sealing system of steam power plant as claimed in claim 2, it is characterized in that: said seal ring is arranged on the sidewall of said exhaust cavity.
4. the sealing system of steam power plant as claimed in claim 1; It is characterized in that: the sealing system of said steam power plant also comprises the refluence ring of the end blade outlet steam flow downstream labyrinth casing that is used to limit said rotor, and said refluence ring is fixedly installed on the said labyrinth casing.
5. the sealing system of steam power plant as claimed in claim 1 is characterized in that: the sealing system of said steam power plant also comprises the dividing plate that is arranged in the said cylinder body and the packing parts between the said epitrochanterian blade.
6. the sealing system of steam power plant as claimed in claim 5; It is characterized in that: said dividing plate is provided with groove; Said blade is provided with the protruding back-up ring that the groove with said dividing plate is complementary, and said packing parts are arranged between the groove and said protruding back-up ring of said dividing plate.
7. the sealing system of steam power plant as claimed in claim 6; It is characterized in that: said packing parts comprise first labyrinth ring; One opening end of said first labyrinth ring is flush-mounted on the groove of said dividing plate, and another opening end of said first labyrinth ring extends to said protruding back-up ring.
8. the sealing system of steam power plant as claimed in claim 1 is characterized in that: the sealing system of said steam power plant also comprises the shroud on the blade that is fixedly installed in said rotor and forms second labyrinth ring of Honeycomb steam seal around said shroud and with said shroud.
9. the sealing system of steam power plant as claimed in claim 1; It is characterized in that: the sealing system of said steam power plant comprises also and being used for the lead guide ring of said dividing plate nozzle of said epitrochanterian velocity stage blade outlet steam that said guide ring is fixedly installed on the said cylinder body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011202407620U CN202170816U (en) | 2011-07-09 | 2011-07-09 | Steam sealing system of steam power device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011202407620U CN202170816U (en) | 2011-07-09 | 2011-07-09 | Steam sealing system of steam power device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202170816U true CN202170816U (en) | 2012-03-21 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011202407620U Expired - Lifetime CN202170816U (en) | 2011-07-09 | 2011-07-09 | Steam sealing system of steam power device |
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| Country | Link |
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| CN (1) | CN202170816U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102230397A (en) * | 2011-07-09 | 2011-11-02 | 潍坊雷诺特动力设备有限公司 | Steam sealing system for steam power device |
| CN105508621A (en) * | 2016-02-01 | 2016-04-20 | 重庆齿轮箱有限责任公司 | Sealing device and oil-steam combined sealing device |
| CN109236382A (en) * | 2018-09-11 | 2019-01-18 | 大唐淮北发电厂 | A kind of encapsulating method at turbine shaft seal and its lp outer casing cylinder face |
| CN111532792A (en) * | 2020-04-15 | 2020-08-14 | 常州大学 | High temperature resistant type closes fan |
-
2011
- 2011-07-09 CN CN2011202407620U patent/CN202170816U/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102230397A (en) * | 2011-07-09 | 2011-11-02 | 潍坊雷诺特动力设备有限公司 | Steam sealing system for steam power device |
| CN102230397B (en) * | 2011-07-09 | 2014-10-22 | 潍坊雷诺特动力设备有限公司 | Steam sealing system for steam power device |
| CN105508621A (en) * | 2016-02-01 | 2016-04-20 | 重庆齿轮箱有限责任公司 | Sealing device and oil-steam combined sealing device |
| CN109236382A (en) * | 2018-09-11 | 2019-01-18 | 大唐淮北发电厂 | A kind of encapsulating method at turbine shaft seal and its lp outer casing cylinder face |
| CN111532792A (en) * | 2020-04-15 | 2020-08-14 | 常州大学 | High temperature resistant type closes fan |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: WANG LIJUN Free format text: FORMER OWNER: WEIFANG LEINUOTE POWER EQUIPMENT CO., LTD. Effective date: 20130116 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20130116 Address after: 261021, Shengli West Street, No. 342, Xiguan Street, Weicheng District, Shandong, Weifang Patentee after: Wang Lijun Address before: 261021, Shengli West Street, No. 342, Xiguan Street, Weicheng District, Shandong, Weifang Patentee before: Weifang Leinuo Power Equipment Co.,Ltd. |
|
| ASS | Succession or assignment of patent right |
Owner name: WEIFANG LEINUOTE POWER EQUIPMENT CO., LTD. Free format text: FORMER OWNER: WANG LIJUN Effective date: 20130216 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20130216 Address after: 261021, Shengli West Street, No. 342, Xiguan Street, Weicheng District, Shandong, Weifang Patentee after: Weifang Leinuo Power Equipment Co.,Ltd. Address before: 261021, Shengli West Street, No. 342, Xiguan Street, Weicheng District, Shandong, Weifang Patentee before: Wang Lijun |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20120321 |