EP2516864A1 - Schubausgleich für eine turbomaschine - Google Patents
Schubausgleich für eine turbomaschineInfo
- Publication number
- EP2516864A1 EP2516864A1 EP09806060A EP09806060A EP2516864A1 EP 2516864 A1 EP2516864 A1 EP 2516864A1 EP 09806060 A EP09806060 A EP 09806060A EP 09806060 A EP09806060 A EP 09806060A EP 2516864 A1 EP2516864 A1 EP 2516864A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- turbo
- machine
- balance
- thrust
- bearing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/04—Shafts or bearings, or assemblies thereof
- F04D29/041—Axial thrust balancing
- F04D29/0416—Axial thrust balancing balancing pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/04—Shafts or bearings, or assemblies thereof
- F04D29/041—Axial thrust balancing
- F04D29/0413—Axial thrust balancing hydrostatic; hydrodynamic thrust bearings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/05—Shafts or bearings, or assemblies thereof, specially adapted for elastic fluid pumps
- F04D29/051—Axial thrust balancing
- F04D29/0513—Axial thrust balancing hydrostatic; hydrodynamic thrust bearings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/05—Shafts or bearings, or assemblies thereof, specially adapted for elastic fluid pumps
- F04D29/051—Axial thrust balancing
- F04D29/0516—Axial thrust balancing balancing pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2270/00—Control
- F05D2270/30—Control parameters, e.g. input parameters
- F05D2270/303—Temperature
Definitions
- the present invention relates to a turbo-machine provided with an automatic thrust force balancing system.
- the present turbo-machine resolves the problem of bearing- overload and -failure by being provided with an automatic thrust force balancing system for the internally generated thrust forces in the turbo-machine . Therefore, the thrust bearing only needs to handle a negligible residual thrust force, which remains constant, regardless of variations in process or machine condition.
- turbo-machines for which the automatic thrust force balancing system may be incorporated, comprises multistage (i.e. three or more stages) compressors and pumps, but also large, high-power one-stage or two- stage compressors and pumps, which are typically used in fluid pipeline systems.
- the turbo-machines may be driven by any suitable gas medium, such as gaseous hydrocarbons and steam, for example steam for a steam turbine .
- Turbo-machine safety, reliability and performance will be improved significantly by incorporating the automatic thrust force balancing system into the turbo-machine .
- turbo-machine structured for automatic balancing of fluid-dynamic thrust forces generated within the turbo-machine during operation thereof is hereby provided.
- the turbo-machine is provided with an automatic thrust force balancing system comprising:
- a balance piston attached around a discharge end of a rotating shaft of the turbo-machine for providing a thrust force capable of counter balancing thrust forces generated by impellers in the turbo-machine during operation thereof;
- balance chamber structured for receiving a leakage flow emanating from the turbo-machine during operation thereof, said balance chamber communicating with a downstream side of the balance piston;
- control valve connected to the balance flow return line for regulating the flow rate of the leakage flow.
- control valve is connected to a temperature controller for regulating the degree of opening of the control valve
- the temperature controller is connected to, and receives control signals from, at least one temperature sensor structured to sense and forward the operating
- the automatic thrust force balancing system allows the control valve and the leakage flow rate to be regulated based on the bearing temperature so as to regulate a back pressure on the balance piston and hence regulate the counter
- said balance piston may be cylindrical and disposed within a cylindrical bush so as to provide an annular clearance between the balance piston and the bush, the clearance of which is capable of passing the leakage flow through the annular clearance and into the balance chamber.
- This annular clearance is sufficiently small to allow the leakage flow to experience a pressure drop when passing through the clearance, the leakage flow having a high
- said temperature sensor may be embedded in the thrust bearing.
- said temperature sensor may be embedded in a set of bearing pads of the thrust bearing, for example in a so-called active set of bearing pads of the thrust bearing.
- the present turbo-machine may be comprised of a centrifugal compressor or a centrifugal pump.
- the turbo-machine may be comprised of a one-stage or two-stage turbo-machine, for example a one-stage or two-stage centrifugal compressor adapted for use on a pipeline system.
- turbo-machine may be comprised of a multistage turbo-machine, multi-stage being defined as the three or more stages provided within the turbo-machine .
- the multi-stage turbo-machine may be provided with stages arranged in a so-called “in-line” configuration or, alternatively, arranged in a so-called “back-to-back” configuration.
- Figure 1 shows a conventional four-stage compressor having its stages arranged in an "in-line” configuration, the figure also showing details of the compressor in an enlarged
- Figure 2 shows different pressure profiles and pressure- affected areas over the internal components of the
- Figure 4 shows a diagram of the loading on the thrust bearing due to variation of internally generated thrust forces according to process and machine conditions
- Figure 5 shows various views and sections of a typical hydrodynamic thrust bearing used for this class of turbo- machines ;
- Figure 6 shows various views and sections of four-stage compressor structured in accordance with the present
- Figure 7 shows a diagram of the correlation between thrust bearing load and pad temperature
- Figure 8 illustrates an alternative multi-stage compressor structured in accordance with the present invention and having its stages arranged in a "back-to-back" configuration.
- a centrifugal compressor with a conventional thrust balancing system is shown in figure 1.
- Gas at pressure Ps enters the compressor at a suction flange 1, after which the gas is compressed by four impellers 2 which are driven by a rotating shaft 3 within the compressor.
- the impellers 2 increase the gas pressure from Ps at entry to Pd at a discharge flange 4.
- Each impeller 2 discharges its gas flow into a stationary- component called a diaphragm 28.
- diaphragm 28 is to convert the kinetic energy of the received gas flow into pressure recovery before returning the gas flow to the next impeller 2.
- Each impeller/diaphragm combination is called a stage 29, and the respective stages 29 are stacked together to form a complete inner assembly 16, which is commonly called a bundle.
- the inner assembly 16 is
- a balance piston 5 is attached at a discharge end of the rotating shaft 3.
- One important function of this balance piston 5 is to control a gas leakage flow from a suction end to the discharge end of the compressor.
- the balance piston 5 is structured so as to provide a close- fitting annular clearance between the balance piston 5 and a bush 6 in the casing 11. The gas leakage flow, which
- balance piston 5 Another important function of the balance piston 5 is to provide a thrust force which counter balances the thrust forces generated by the impellers 2. The perfect thrust balance, however, is only achieved for one operating _ condition. Variations in process conditions, and
- a thrust bearing 9 located at the suction end of the compressor and supporting the rotating shaft 3.
- This thrust bearing 9 comprises two sets of bearing pads 15 and 17.
- the residual thrust force is transferred from the rotating shaft 3 to the thrust bearing 9 by means of a thrust collar 10 which is disposed between the two sets of bearing pads 15, 17, and which is shrunk onto the rotating shaft 3 at the suction end of the compressor.
- Figure 2 shows, on one side, a first pressure profile
- figure 3 shows that the net (or residual) thrust force acting on the impellers 2 is oppositely directed to the net thrust force acting on the balance piston 5.
- the total thrust force of 50 Tons on the impellers 2 is not quite balanced by the counter thrust force of 45 Tons on the balance piston 5, leaving a residual thrust force Ttb of 5 Tons acting on the thrust bearing 9.
- the reason for having such a residual thrust force Ttb acting on the thrust bearing 9 instead of having perfectly balanced internal thrust forces acting thereon, is to ensure that a residual thrust force is always acting on the stationary, active set of bearing pads 17 located on the active side of the thrust bearing 9 (see figure 5) .
- Figure 4 shows a diagram of the manner in which loads on the thrust bearing 9 change in response to variations in the internally generated thrust forces, which result from changes in process and machine condition (wear and fouling) .
- curve A-A shows the specific bearing load plotted against gas flow for a new compressor at rated speed and suction and discharge pressures.
- curve B-B shows the specific bearing load plotted against flow for a new compressor, and at rated speed and discharge pressure, but with a 10 % increase in suction pressure.
- curve C-C shows the specific bearing load plotted against flow for a worn compressor at rated process conditions.
- curve D-D shows the performance characteristics of a compressor structured in accordance with the present
- This compressor incorporates an automatic thrust force balancing system for allowing the compressor to
- Figure 4 also shows a thrust bearing failure zone defined between specific bearing load failure thresholds (Fw-Fw) , which represents a worn bearing, and (Fn-Fn) , which
- the failure threshold (Fn-Fn) is at approximately 500 psi (3.45 N/mm 2 ) .
- the failure threshold (Fw-Fw) can fall to as low as 375 psi (2.6 N/mm 2 )
- the very essence of the present turbo-machine is to provide a technical solution allowing the thrust bearing of the turbo- machine to better withstand these excursions in thrust forces at high speeds .
- FIG. 5 details the typical hydrodynamic thrust bearing 9 that is used for large, high-speed turbo-machines.
- This hydrodynamic thrust bearing 9 is provided with tilting sets of bearing pads 17 and 15, each of which is provided with a pivot 27 for allowing some tilting of the set of bearing pads.
- the pivots 27 are made of hardened steel and are free to pivot on a bearing carrier 20. Similar to the thrust bearing shown in figure 1, the set of bearing pads 17 is active and the set of bearing pads 15 is inactive.
- the base material for the tilting sets of bearing pads 17 and 15 is usually steel with a thin layer of white metal 18 bonded to the steel so as to form a bearing surface in contact with the rotating thrust collar 10. Due to its high criticality, the thrust bearing 9 is commonly equipped with an on-line condition monitoring system which provides monitoring, alarm and automatic machine shutdown on high values of the following critical parameters:
- a compressor structured in accordance with the present invention and incorporating an automatic thrust force balancing system is illustrated in figure 6.
- the balancing system is designed in a manner allowing the counter balance thrust force from the balance piston to be
- the thrust force of the balance piston 5 on the rotating shaft 3 is regulated by a control valve 25, which is installed in the balance return line 8, and which varies a back pressure Pbc (see figs. 1 and 2) on the balance piston 5.
- the selected control parameter is the temperature of the active set of bearing pads 17, the temperature of which is monitored by the temperature sensor 22.
- the sensor 22 relays an output signal to a temperature controller 26, which in turn outputs a 4-20 mA (milliampere) signal to the control valve 25 so as to regulate the degree of opening of the control valve 25.
- FIG. 7 shows a temperature-load curve (Tb-Tb) of the correlation between thrust bearing load and bearing pad temperature . Either of these two parameters could have been used as the selected control parameter for regulating the control valve 25. In this embodiment, however, the embedded temperature sensor 22 is selected due to its excellent reliability and minimum requirement for re-calibration, as compared to measuring the thrust bearing load by means of load cells.
- the desired bearing load is 20 % of the rating for the thrust bearing 9.
- the desired load indicates a bearing pad temperature of 70 degrees Celsius.
- a 70 degrees Celsius temperature setting is then set at the temperature controller 26, after which the control valve 25 regulates accordingly until the bearing pad temperature stabilizes at 70 degrees Celsius.
- the temperature-load curve (Tb-Tb) is obtained from the bearing manufacturer, and the temperature at zero load and rated speed can be confirmed during commissioning by- searching for the lowest temperature set point that moves the rotor of the turbo-machine from the active set of bearing pads 17 to the inactive set of bearing pads 15, as indicated by the first, axial proximeter probe 23.
- the diameter of the balance piston 5 is designed to balance the highest calculated thrust load from the impellers 2 when the control valve 25 is in its fully open position. This maximum thrust load is based on the process and machine conditions yielding the highest impeller thrust force. For all other operating parameters, such as process flow rates, pressures, gas densities and machine conditions, the control valve 25 will modulate the back pressure Pbc on the balance chamber 7, and also the counter thrust force on the balance piston 5, so as to maintain a minimum and constant load on the active set of thrust bearing pads 17.
- the benefits of this novel compressor is shown clearly in figure 4.
- curve D-D the automatic thrust force balancing system of the present compressor ensures that the thrust bearing 9 is always automatically maintained on a low and constant loading regardless of changes in process and machine conditions.
- An additional benefit of using the present compressor with such a thrust force balancing system is a reduction in the bearing and balance flow power losses, which increases the turbo- machine's efficiency in the order of 1-3 %, depending on the duty of the compressor (turbo-machine) .
- Figure 8 shows an alternate design of a multi-stage
- This compressor is effectively split into two sections, including a low pressure section 31 and a high pressure section 32.
- the two sections 31, 32 are statically connected via a crossover line 33.
- the two sections 31, 32 are also dynamically separated by means of a close-fitted centre bush 34 and a centre sleeve 35.
- the centre sleeve 35 also acts as a balance piston with a high pressure discharge pressure on one side, and a low pressure discharge pressure on the other side.
- the compressor is provided with an additional combination of a centre bush 36 and a centre sleeve 37.
- This arrangement reduces the pressure at the discharge end 38 of the compressor from low pressure discharge pressure to low pressure suction pressure at the suction end 39 of the compressor.
- This centre sleeve 37 acts as a separate balance piston.
- the back pressure Pbc on the centre sleeve 37 can be regulated by means of the control valve 25 so as to
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/NO2009/000445 WO2011078680A1 (en) | 2009-12-23 | 2009-12-23 | Turbo-machine thrust balancer |
Publications (1)
Publication Number | Publication Date |
---|---|
EP2516864A1 true EP2516864A1 (de) | 2012-10-31 |
Family
ID=42671706
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP09806060A Withdrawn EP2516864A1 (de) | 2009-12-23 | 2009-12-23 | Schubausgleich für eine turbomaschine |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP2516864A1 (de) |
WO (1) | WO2011078680A1 (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3734080A1 (de) * | 2019-05-01 | 2020-11-04 | Garrett Transportation I Inc. | Einstufiger kompressor mit achsschubunterdrückungsabschnitt |
EP3808984A1 (de) * | 2019-10-15 | 2021-04-21 | Sulzer Management AG | Von prozessflüssigkeit geschmierte pumpe und meerwasserinjektionssystem |
CN114622995A (zh) * | 2020-12-14 | 2022-06-14 | 盖瑞特动力科技(上海)有限公司 | 具有抑制推力载荷的排放流体系统的电子辅助涡轮增压器 |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8925197B2 (en) * | 2012-05-29 | 2015-01-06 | Praxair Technology, Inc. | Compressor thrust bearing surge protection |
FR2997739B1 (fr) * | 2012-11-07 | 2015-01-09 | Thermodyn | Compresseur comprenant un equilibrage de poussee |
EP2976505B1 (de) * | 2013-03-18 | 2021-08-11 | OneSubsea IP UK Limited | Ausgleichskolben für mehrphasige flüssigkeitsverarbeitung |
US11377954B2 (en) | 2013-12-16 | 2022-07-05 | Garrett Transportation I Inc. | Compressor or turbine with back-disk seal and vent |
WO2016038661A1 (ja) * | 2014-09-08 | 2016-03-17 | 三菱重工コンプレッサ株式会社 | 回転機械 |
EP3121450B1 (de) * | 2015-07-23 | 2020-09-02 | Sulzer Management AG | Pumpe zum fördern eines fluids mit variierender viskosität |
CN105864093B (zh) * | 2016-05-25 | 2018-06-26 | 浙江科尔泵业股份有限公司 | 多级离心式高压液化烃泵 |
CN105889080B (zh) * | 2016-05-25 | 2018-06-26 | 浙江科尔泵业股份有限公司 | 高压液化烃泵的温升控制系统 |
US11353036B2 (en) | 2017-12-01 | 2022-06-07 | Nuovo Pignone Tecnologie Srl | Balancing system and method for turbomachine |
RU181078U1 (ru) * | 2018-02-13 | 2018-07-04 | Федеральное государственное автономное образовательное учреждение высшего образования "Северо-Восточный федеральный университет имени М.К.Аммосова" | Электронасосный агрегат секционного типа |
CN112368481B (zh) * | 2018-09-14 | 2023-09-01 | 开利公司 | 构造成控制抵靠磁性马达推力轴承的压力的压缩机 |
CN111120414B (zh) * | 2019-12-13 | 2021-06-15 | 西安航天动力研究所 | 一种大流量大功率预压泵轴向力平衡结构及方法 |
EP3936726A1 (de) * | 2020-07-07 | 2022-01-12 | Sulzer Management AG | Anpassung der ausströmmenge einer mehrstufigen pumpe durch einstellung des spiels des entlastungskolbens |
CN112343668B (zh) * | 2020-11-03 | 2023-07-21 | 上海齐耀动力技术有限公司 | 超临界二氧化碳tac机组推力平衡系统及控制方法 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3895689A (en) | 1970-01-07 | 1975-07-22 | Judson S Swearingen | Thrust bearing lubricant measurement and balance |
SU641167A1 (ru) * | 1976-04-17 | 1979-01-05 | •iATEflfifO- TiiXSrn^f-Sk^o | Способ регулировани осевого усили турбомашины |
US4385768A (en) | 1979-07-19 | 1983-05-31 | Rotoflow Corporation, Inc. | Shaft mounting device and method |
US4884942A (en) | 1986-06-30 | 1989-12-05 | Atlas Copco Aktiebolag | Thrust monitoring and balancing apparatus |
JP3143986B2 (ja) | 1991-10-14 | 2001-03-07 | 株式会社日立製作所 | 一軸多段遠心圧縮機 |
US6310414B1 (en) | 1994-06-21 | 2001-10-30 | Rotoflow Corporation | Shaft bearing system |
US6367241B1 (en) | 1999-08-27 | 2002-04-09 | Allison Advanced Development Company | Pressure-assisted electromagnetic thrust bearing |
GB2462635B (en) * | 2008-08-14 | 2010-07-14 | William Paul Hancock | Turbo-machines thrust balancer |
-
2009
- 2009-12-23 EP EP09806060A patent/EP2516864A1/de not_active Withdrawn
- 2009-12-23 WO PCT/NO2009/000445 patent/WO2011078680A1/en active Application Filing
Non-Patent Citations (1)
Title |
---|
See references of WO2011078680A1 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3734080A1 (de) * | 2019-05-01 | 2020-11-04 | Garrett Transportation I Inc. | Einstufiger kompressor mit achsschubunterdrückungsabschnitt |
EP3808984A1 (de) * | 2019-10-15 | 2021-04-21 | Sulzer Management AG | Von prozessflüssigkeit geschmierte pumpe und meerwasserinjektionssystem |
CN114622995A (zh) * | 2020-12-14 | 2022-06-14 | 盖瑞特动力科技(上海)有限公司 | 具有抑制推力载荷的排放流体系统的电子辅助涡轮增压器 |
US11933312B2 (en) | 2020-12-14 | 2024-03-19 | Garrett Transportation I Inc | E-assist turbocharger with bleed fluid system connecting compressor section to web ring of turbine section for thrust load suppression |
CN114622995B (zh) * | 2020-12-14 | 2024-06-07 | 盖瑞特动力科技(上海)有限公司 | 具有抑制推力载荷的排放流体系统的电子辅助涡轮增压器 |
Also Published As
Publication number | Publication date |
---|---|
WO2011078680A1 (en) | 2011-06-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2011078680A1 (en) | Turbo-machine thrust balancer | |
GB2462635A (en) | Turbo-machine axial thrust balancing | |
KR890001725B1 (ko) | 유체누설을 감소시킨 회전식 유체처리장치 | |
EP3376079B1 (de) | Trockengasdichtung | |
CA1327481C (en) | Centrifugal pump with hydraulic thrust balance and tandem axial seals | |
US7964982B2 (en) | Axial in-line turbomachine | |
US6310414B1 (en) | Shaft bearing system | |
US6616423B2 (en) | Turbo expander having automatically controlled compensation for axial thrust | |
RU2557143C2 (ru) | Динамическая балансировка осевого усилия для центробежных компрессоров | |
US5248239A (en) | Thrust control system for fluid handling rotary apparatus | |
US5312226A (en) | Turbo compressor and method of controlling the same | |
WO1991014853A1 (en) | Control system for regulating the axial loading of a rotor of a fluid machine | |
US7731476B2 (en) | Method and device for reducing axial thrust and radial oscillations and rotary machines using same | |
JP2011236902A (ja) | 圧縮機ロータ用バランスドラム構成 | |
CZ297939B6 (cs) | Zarízení pro kompenzaci axiálního posunu u turbostroju | |
JPH11257293A (ja) | 遠心圧縮機の制御装置 | |
EP3436666A1 (de) | Radialturbomaschine mit axialschubausgleich | |
GB2493737A (en) | Turbo-machine automatic thrust balancing | |
KR102239817B1 (ko) | 터보 압축기 | |
WO2008018800A1 (en) | Bearing system for rotor in rotating machines | |
EP3916255B1 (de) | Mehrstufige axiallager für turbinen | |
CN221568936U (zh) | 一种轴向力平衡的立式多级磁力泵 | |
CN113090528B (zh) | 压缩机、轴承磨损程度检测方法和空调系统 | |
CN114198314B (zh) | 一种双止推超高压锅炉给水泵 | |
JPS60209603A (ja) | 軸流圧縮機 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20120702 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR |
|
DAX | Request for extension of the european patent (deleted) | ||
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20140701 |