CN1290118A - Direct arc furnace supplied by controllable current - Google Patents
Direct arc furnace supplied by controllable current Download PDFInfo
- Publication number
- CN1290118A CN1290118A CN00101646A CN00101646A CN1290118A CN 1290118 A CN1290118 A CN 1290118A CN 00101646 A CN00101646 A CN 00101646A CN 00101646 A CN00101646 A CN 00101646A CN 1290118 A CN1290118 A CN 1290118A
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- Prior art keywords
- arc
- furnace
- current
- inductor
- electric
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- 238000010891 electric arc Methods 0.000 claims description 11
- 230000008859 change Effects 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 4
- 239000000956 alloy Substances 0.000 abstract description 3
- 229910045601 alloy Inorganic materials 0.000 abstract description 3
- 238000000034 method Methods 0.000 abstract description 3
- 238000003723 Smelting Methods 0.000 abstract description 2
- 229910052742 iron Inorganic materials 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 229910052751 metal Inorganic materials 0.000 abstract description 2
- 150000002739 metals Chemical class 0.000 abstract 1
- 239000003990 capacitor Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 7
- 230000001105 regulatory effect Effects 0.000 description 7
- 230000005611 electricity Effects 0.000 description 6
- 238000013461 design Methods 0.000 description 5
- 238000012937 correction Methods 0.000 description 4
- 230000001939 inductive effect Effects 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004070 electrodeposition Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000009970 fire resistant effect Effects 0.000 description 2
- 238000007499 fusion processing Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002964 excitative effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000001915 proofreading effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B7/00—Heating by electric discharge
- H05B7/02—Details
- H05B7/144—Power supplies specially adapted for heating by electric discharge; Automatic control of power, e.g. by positioning of electrodes
- H05B7/148—Automatic control of power
- H05B7/156—Automatic control of power by hydraulic or pneumatic means for positioning of electrodes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Discharge Heating (AREA)
- Control Of Electrical Variables (AREA)
Abstract
Method to feed a three-phase direct-arc electric furnace with controlled current and also a three-phase electric furnace thus fed for the smelting of metals and advantageously but not essentially for iron-based alloys, the furnace comprising means (GI) for regulation of the length of the arc, the mains supply of the furnace including at least one medium voltage line and a transformer to serve the arc furnace, an element to regulate the arc current being comprised in each phase in the segment consisting of at least one inductor, a thyristor-controlled valve or alternatively a regulation element consisting of a saturable reactor being included in parallel with at least part of the inductor, one or the other of these regulation elements cooperating with a device (S1) to measure the intensity of the arc current and with an assembly (GC) that controls the arc current of the furnace by means of action on the overall value of the equivalent series reactance.
Description
The application be submit to November 29 nineteen ninety, application number is 90109552.4, be entitled as the dividing an application of application of " by the direct arc furnace of controllable current feed and to the method for direct arc furnace feedback with controllable current ".
The present invention relates to be provided with the three-phase direct-arc electric furnace of controllable current.
The present invention is used for smelting metal, particularly the three-phawse arc furnace of iron and alloy thereof.
Direct arc furnace mainly is used to melting and purified steel at present, and almost is three-phase furnace entirely.
In recent two decades, single stove power is greatly improved, and plant capacity increases to greater than 85MW and 120MVA from 16MW and 20MVA.
Big like this power brings voltage disturbance (fluctuation) to power supply grid, and because big problem such as sizable phase shift that inductive load caused.
For proofreading and correct the phase difference that inductive load thus causes and reducing voltage fluctuation, modern compensation technique has been used the various inactivity compensation devices that controllable diode is moved together that have.
Principles of Regulation are shown in Fig. 1 and as described below:
Line ball is arranged in parallel in three inductors and the three-phase, and this line is as electric furnace power supply place of forceful electric power sense load; These inductors are powered by thyristor T, and its conduction angle is controlled according to the electric current that device SI detects.
Total reactive power that this regulating system keeps stove to use is constant and in zero place's balance, during inductor L1 and L2 and many group power factor correction capacitor CR are linked on the voltage source line.
Many group power factor correction capacitor CR add that suitable inductor also can realize the function of the harmonic wave that filtering is produced by electric furnace and bucking-out system.
Change electrode height by means of suitable hydraulic means GI, making great efforts to keep the resistance of electric arc is constant, the active power of regulating electric furnace electric arc whereby.
For difficulty and the shortcoming that the pattern that overcomes the electric current that this indirect regulation draws is brought, produced the direct-arc electric furnace recently, this pattern has a single electrode, electric current return shell by electric furnace.
The supply current of electric arc, the rectifying device of being made up of controllable diode or thyristor provides.There are two significant drawback in this system.On the one hand it is difficult to obtain the return path of electric current, and commutation system produces very strong odd harmonic on the other hand simultaneously.
In order to eliminate these critical defects of these two kinds of arc furnace, the applicant designs, tests and implemented the present invention, and it is to be scheduled to purpose as its target.
The present invention is provided with the three-phase direct-arc electric furnace of controllable current, can be advantageously but be not only to be used for the melting ferrous alloy, this electric furnace comprises the device that is used for regulating by the height that acts on electrode arc length, comprise supply with the arc furnace electricity consumption at least one in the electric furnace main power source of line ball and a transformer, the device of in that part of line ball and transformer and adjusting arc current that comprise at least one inductor in each connects in mutually, with a device that is used to measure the current strength of being drawn by electric arc, this electric furnace is characterised in that: comprise at least one controlled thyristor switch, at least a portion parallel connection of it and first inductor.
According to the present invention, controlling organization directly acts on the arc current of electric furnace, to determine operating point and to reduce disturbance, this unlike the prior art, prior art allows the interior electric current of electric furnace freely generate, and only control with the hydraulic system of regulating arc length, following anti-fluctuation control system then attempts to regulate the state of main power source side.
Present on the other hand three-phawse arc furnace is typically connected to that work alone and the bucking-out system electric furnace parallel connection, according to three electric arcs of electric furnace of the present invention, applies one by the first inductor L according to a kind of design of its solution by giving each electric arc
1First basic current of restriction is powered.Second electric current is by the second inductor L
2Be added on first electric current, second electric current is by means of thyristor T, considers that according to the value of analyzing first basic current and/or its initial slope or trend the transfer function of electric arc running status operates and regulate.
According to another kind of scheme, except analyzing its value and/or initial slope, also want analytical equipment everywhere, particularly transformer has the state that carries the electric weight that need discuss at the tap changer place.
According to the another scheme of the design of solution, saturable reactor RS can suitably be used for replacing inductor L
1And L
2With thyristor T.
According to the present invention, the power factor correction capacitor also as absorbing by the filter of electric furnace to the harmonic wave of electrical network generation, is positioned in the mode with the prior art all fours and is connected in parallel on middle the pressure on the bus-bar, but capacitance value is much smaller.
With reference to the accompanying drawing that provides as non-limitative example, Fig. 1 represents prior art.
Fig. 2 represents the present invention, and the difference of invention and prior art is understood.The various schemes of Fig. 3 and 4 expression solution designs.
Look in detail now the content of prior art and invention.
The part of point unlike the prior art of the present invention between middle line ball and furnace transformer.
Among Fig. 1, inductor L1Has such effect, according to available transmitted power, electricity Arc length degree and radiation index by selected its value, make the operating point optimization of electric furnace also more flexible.
Inductor L1Selected realize that by definite operating point following phase will be weighed in this operating point Anti-requirement: both guaranteed suitable transfer power and concerning the fusion process technological requirement, had enough High arc current, the peak point current when being limited in electric pole short circuit again simultaneously.
Choose inductor L1Affect indirectly the arc heat radiation, it should consider production efficiency Required minimum of a value is decided with the restriction of wearing and tearing because of fire-resistant lining and in accordance with relevant safety margins Maximum between change.
Thereby the inductive reactive power that compensation is drawn by electric furnace is important.
Necessary capacitive character reactive compensation power is to obtain like this: fixing PFC capacitor group CR (Y-connection of point insulating or ground connection normally) is parallel to middle line ball, and with the inductor L that fixes2With controlled thyristor switch T (by thyristor control Inductor) obtain variable inductance. Inductor L2It is delta-connection.
Inductor LF also is used as wave filter and is positioned to and IGCT T and capacitor CR is in series.
By the average power factor that requires to obtain height than the power supply department regulation at power supply point, and the compensation reactive power peak value that causes voltage fluctuation is disturbed in the electrical network quilt to draw as quick as thought, the demand that variable backoff can not all be described is rational.
Capacitor group CR and inductor L
2Select according to the maximum reactive power (equaling the stove short-circuit power) that electric furnace requires, and this reactive power will be with one because described compensation arrangement (CR+L
2+ T) undercompensation so proofread and correct greater than 1 coefficient.
Inductor LF also considers the effect of ripple device in addition, and settles to such an extent that connect with thyristor T and capacitor CR.
By the measurement of each reactive current of drawing of power supply phase of electric furnace, with device SI by carrying out this device generation arc current control system feedback signal mutually.
In institute is free, the capacity current of drawing by capacitor group CR must with by electric furnace with by the inductor L of thyristor T control
2The inductance current of being drawn balances each other.
Second adjusting device of figure acceptance of the bid GI constitutes relevant with the circuit of control arc resistance.
For example, the arrangement of known suitable fluid pressure type servomechanism GI is vertically moved electrode, to keep the electric furnace impedance constant.
Its time constant of mechanical adjustment is slower than above-mentioned electricity significantly and regulates pattern, thereby not too effective to the effect of electrical interference.
Forward the present invention who is shown in Fig. 2 briefly below to, can find inductor L
1The same purpose of the like that is comprised in the prior art shown in realization Fig. 1.
Use fixed inductor L
2Can obtain variable inductor with the valve T of thyristor operation, and and inductor L
1Be installed in parallel.Thereby provide variable inductance with furnace power series connection.
Device SI measures the current's intensity of being drawn by electric arc, and sends the control system that a signal removes to drive thyristor T.
The electric current that might keep by this way being drawn by electric furnace is constant in very wide limit, thereby obtains the power supply of a controllable current.
The opposite variation of equivalent inductor impedance that the variation of arc impedance is arranged by series connection compensates, and this equivalent inductor is by L
1And L
2Formation in parallel.
For example, if electric arc trends towards disappearing, then reduce inductance and increase electric current.
Otherwise, if electrode by just in the waste material institute short circuit of melting, then the inductance of inductor changes to maximum, so that the voltage drop that restriction causes in the electrical network.In other words, there is a kind of trend, proofreaies and correct the cause of disturbance in the electrical network, do not proofread and correct its consequence with static variable equalizer the prior art and do not resemble.
The automatic control of the inductance of equivalent series depends on arc current, thereby the content of the innovation of configuration shown in forming.
Illustrated control also can with arc length hydraulic regulating device GI collaborative work.
Though the control of two kinds of patterns can be kept constant impedance in the stove side by its purpose, they have some difference.The adjusting device GI that acts on arc length and influence electrode position only can change the active component of impedance, and equivalent series inductance (L
1L
2Parallel connection) electricity is regulated, and directly changes reaction component by acting on arc current, also equivalent resistance is worked.
Have, time constant is very different again, because a kind of situation relates to mechanical effect, and another kind of situation only comprises the effect of electricity.
Adjusting by the equivalent series reactance of carrying out mutually, the intrinsic impedance imbalance that constitutes (outputing to electric arc from furnace transformer) at the electric furnace secondary circuit is corrected, three electric currents in mutually can keep constant, thereby have overcome so-called " cold phase " (coldphase) and " display of unrestraint of excessive haughtiness " (wild phase) problem.
Handle according to the signal that comes from monitor SI with the inductor of thyristor T control in the technology that the prior art neutralization here proposes, these signals are handled by a control device GC.
Here in the technology of Ti Chuing, control device GC also can receive the signal of other electric quantity change in the reflection circuit each several part.Therefore, for example it can help the measuring-signal that line ball comes in the transformer TV reception by nationality, again for example, can receive the electrode position signal that obtains by control GC, this can receive the signal from other sources, and for example, transformer has idling to change the signals position of the switch or other settings.
Also have, control device GC prevents that by DC component in the electric current of inductor it is saturated with eliminating.
Power factor correction capacitor CR receives middle line ball, and the reactive factor of the power that its handlebar is drawn by electric furnace is corrected to the effect in the given limit of power supply department.
As at Fig. 1, as seen, formation according to the present invention provides those same parts that comprised in the common formation in 2.But these partial functions are utilized usefulness in a different manner.
The application different to the each several part that different set point values is arranged brought some important savings on the structure.
Can fluctuation disturbance equal in the effective power of supplying with electric furnace and that in electrical network, produce equate to carry out the contrast of two kinds of solutions under the condition.
Inductor L
11, although bigger reactance is arranged, only be injected into part electric furnace running current in the present invention usually.With regard to its power, thus with regard to its price, and consider the safety factor that short circuit is transshipped, approximately be that Fig. 1 constitutes desired 30-40%.
Power factor also reduces much by positive electricity container C R.In fact, under Fig. 1 situation, have been noted that as us capacitive reactive power is selected in than on the also big value of short-circuit power on the electrode.Under the situation of Fig. 2, only need to proofread and correct a part of reactive factor of being drawn by electric furnace at operating point, this reactive power result minimizing is about 70-80%.
The inductor L that is controlled by controlled thyristor switch T
2Value can be taken as zero in theory, can allow the scope of electric furnace series reactance maximal regulated.
Compare with Fig. 1 example, if considered the prevention factor, the technologic reason that links mutually owing to the example with fusion process and thyristor T can make it reduce about 80-90%.
According to the present invention, this selectes thyristor T down in low-voltage and not too big electric current, and the coefficient that set point value reduces is approximately 40-50%.This value obtains with calculating the product of maximum current that the maximum voltage be added on the thyristor T multiply by by it.
The saving that obtains on the each several part structure, also must take into account the improvement of working cost aspect, this improves mainly due to the electric variation gained that has reduced electric arc.
In fact, balanced raising of current stability and three phase currents has realized higher production process efficient, the less electrode and the wearing and tearing of fire-resistant lining, and when short circuit takes place less electronic stress.
Because design of the present invention basis is that control is connected on reactance in the electric furnace lateral circuit automatically, so can propose to realize by different way some variation schemes of this control.
Fig. 3 a is first kind of this variation scheme, has cancelled inductor L
2But keep by controlled thyristor switch T; See in the front as us, comprise inductor L
2Be not substantial being actually because technologic reason.
Fig. 3 b is another variation scheme, and it proposes to regulate is discontinuous, is classification.From inductor L
1Tell some centre taps, control by the controlled thyristor switch.This scheme can make control simpler, but does not allow the impedance of fine tuning furnace side, thereby does not allow the fine tuning phase current.
The scheme of Fig. 4 proposes to use saturable reactor RS and replaces L
1, L
2And T.
Saturable reactor is excitatory by Constant Direct Current electric current suitable, that supplied with by control circuit GC.Its characteristic is to be low reactance value under than the low little electric current of electric furnace rated current IN, and to be high reactance value when high electric current.
This can be limited overcurrent considerably, thus the effect of deboost fluctuation.
This solution advantage is not need complicated control system GC, and in fact, when having set corresponding to the direct current of the IN of electric furnace operating point, saturable reactor promptly automatically limits overcurrent.
Control circuit GC is according to the fixing exciting curent of saturable reactor of electric furnace operating point.
For getting this function, adjuster GC connects with electrode height adjuster GI and furnace transformer on load voltage tap-change.
According to a scheme, adjuster GC is not only with reference to coming the signal of adjuster GI, also the state of the electric weight that variant position is comprised in the analytical equipment.
Claims (3)
1. be provided with the three-phase direct-arc electric furnace of controllable current, comprise:
Electrode;
Be used to regulate electrode height so that the device of the arc length that control is produced;
A main power source, be included as electric furnace provide electric current at least one in line ball and a furnace transformer, a part in the described main power source is used for connecting described line ball and described furnace transformer and has at least one first inductor and the device of measuring the current strength of being drawn by electric arc; It is characterized in that:
A controlled thyristor switch, it with at least one described first inductor parallel connection to change the series reactance of described part.
2. electric furnace as claimed in claim 1 comprises the second inductor (L that links with the controlled thyristor switch
2).
3. as any described electric furnace among the claim 1-2, wherein controlled thyristor switch (T) is handled by control device (GC).
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT08352089A IT1236363B (en) | 1989-11-30 | 1989-11-30 | DIRECT CURRENT ELECTRIC ARC OVEN AND CONTROLLED CURRENT SUPPLY PROCEDURE OF A DIRECT ARC ARC OVEN |
| IT83520A/89 | 1989-11-30 | ||
| EP90116833.6 | 1990-09-03 | ||
| EP90116833A EP0429774A1 (en) | 1989-11-30 | 1990-09-03 | Direct-arc electric furnace fed with controlled current and method to feed a direct-arc furnace with controlled current |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN90109552A Division CN1057658C (en) | 1989-11-30 | 1990-11-29 | Direct electric arc furnace fed by controllable current and method for supplying controllable current to direct electric arc furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1290118A true CN1290118A (en) | 2001-04-04 |
Family
ID=26125444
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN90109552A Expired - Fee Related CN1057658C (en) | 1989-11-30 | 1990-11-29 | Direct electric arc furnace fed by controllable current and method for supplying controllable current to direct electric arc furnace |
| CN00101646A Pending CN1290118A (en) | 1989-11-30 | 2000-01-25 | Direct arc furnace supplied by controllable current |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN90109552A Expired - Fee Related CN1057658C (en) | 1989-11-30 | 1990-11-29 | Direct electric arc furnace fed by controllable current and method for supplying controllable current to direct electric arc furnace |
Country Status (4)
| Country | Link |
|---|---|
| CN (2) | CN1057658C (en) |
| AU (1) | AU641195B2 (en) |
| BR (1) | BR9006066A (en) |
| CA (1) | CA2030686C (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111864735A (en) * | 2020-07-22 | 2020-10-30 | 安徽交通职业技术学院 | Switching compensation system |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE501025C2 (en) * | 1993-03-18 | 1994-10-24 | Asea Brown Boveri | Oven |
| US7496275B2 (en) * | 2000-03-14 | 2009-02-24 | Thomson Licensing | System and method for providing recording function when no program information is available |
| RU2725489C2 (en) | 2015-06-05 | 2020-07-02 | Хэтч Лтд. | Flicker suppression at electric arc furnace |
| CN105158540B (en) * | 2015-08-11 | 2018-04-24 | 南京师范大学 | A kind of arc current evaluation method using electric arc inductance correction factor |
| CN106931796B (en) * | 2017-03-14 | 2019-01-22 | 四方继保（武汉）软件有限公司 | Based on the electrodes in mine hot stove control method for calculating electrode payload resistance in furnace |
| IT201800004847A1 (en) * | 2018-04-24 | 2019-10-24 | METHOD OF MELTING IN AN ELECTRIC ARC OVEN AND RELATED EQUIPMENT | |
| CN109000481B (en) * | 2018-09-21 | 2023-07-25 | 大连重工机电设备成套有限公司 | Variable direct current flows back to Lu Tiege gold ore deposit hot stove |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2632862A (en) * | 1950-05-02 | 1953-03-24 | Westinghouse Electric Corp | Regulating system |
-
1990
- 1990-11-23 CA CA002030686A patent/CA2030686C/en not_active Expired - Fee Related
- 1990-11-26 AU AU66965/90A patent/AU641195B2/en not_active Ceased
- 1990-11-29 BR BR909006066A patent/BR9006066A/en not_active IP Right Cessation
- 1990-11-29 CN CN90109552A patent/CN1057658C/en not_active Expired - Fee Related
-
2000
- 2000-01-25 CN CN00101646A patent/CN1290118A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111864735A (en) * | 2020-07-22 | 2020-10-30 | 安徽交通职业技术学院 | Switching compensation system |
| CN111864735B (en) * | 2020-07-22 | 2024-04-16 | 安徽交通职业技术学院 | A switching compensation system |
Also Published As
| Publication number | Publication date |
|---|---|
| BR9006066A (en) | 1991-09-24 |
| CA2030686C (en) | 1999-10-05 |
| AU6696590A (en) | 1991-06-06 |
| CN1052585A (en) | 1991-06-26 |
| AU641195B2 (en) | 1993-09-16 |
| CN1057658C (en) | 2000-10-18 |
| CA2030686A1 (en) | 1991-05-31 |
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| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |