CN115430828B - Quantitative constant-speed pouring control method for molten iron of pouring machine - Google Patents
Quantitative constant-speed pouring control method for molten iron of pouring machine Download PDFInfo
- Publication number
- CN115430828B CN115430828B CN202211158884.4A CN202211158884A CN115430828B CN 115430828 B CN115430828 B CN 115430828B CN 202211158884 A CN202211158884 A CN 202211158884A CN 115430828 B CN115430828 B CN 115430828B
- Authority
- CN
- China
- Prior art keywords
- pouring
- micro
- molten iron
- real
- data
- 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.)
- Active
Links
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 80
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 40
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000005266 casting Methods 0.000 claims abstract description 33
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 4
- 238000004364 calculation method Methods 0.000 claims description 8
- 238000011002 quantification Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 3
- 238000013178 mathematical model Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 239000012223 aqueous fraction Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D39/00—Equipment for supplying molten metal in rations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D46/00—Controlling, supervising, not restricted to casting covered by a single main group, e.g. for safety reasons
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
Abstract
The invention relates to the technical field of casting control of casting machines, and discloses a quantitative constant-speed casting control method for molten iron of a casting machine, which comprises the following steps: s1, determining the volume of a molten iron cavity in a casting machine, and carrying out three-dimensional modeling on the molten iron cavity; s2, performing equal-angle dividing according to the water outlet point of the molten iron; s3, slicing the split points in micro-sections after splitting; s4, performing external excision on the model, and inquiring the weight of the rest sliced entities to calculate the weight per degree; s5, summarizing the calculated weight data of each degree into a chart; s6, establishing a database, making a corresponding data block in the database according to chart data, differentiating through a pouring ladle mathematical model to obtain a data table, establishing a program database according to the data table, calculating real-time angular density through database data, multiplying the real-time angular density by a tilting micro-change angle to obtain micro-change pouring weight, and obtaining pouring quantity through pouring micro-integration, thereby realizing accurate quantitative pouring, wherein the pouring precision is about 0.2Kg, and realizing high-precision quantitative pouring.
Description
Technical Field
The invention relates to the technical field of casting control of casting machines, in particular to a quantitative constant-speed casting control method for molten iron of a casting machine.
Background
The pouring machine is special equipment for pouring molten iron in the casting industry, the molten iron is poured into a pouring ladle from a melting furnace, the pouring ladle is mounted on the pouring machine, the pouring machine drives the pouring ladle to perform pouring action, the molten iron is poured into a casting mould to form a part after being cooled, and the pouring machine is mechanical automatic equipment for pouring the molten iron.
At present, the casting machine is used for controlling the casting molten iron amount by three methods:
① The pure manual operation has no automatic quantitative function;
② The weighing sensor is used for detection and quantification, the accuracy of the sensor is limited in that the accuracy of the sensor cannot be accurately quantified, the highest international accuracy of the sensor is one ten thousandth of full range at present, the structural weight of the whole machine is about 6 tons, so that the accuracy of the sensor can only reach 0.6Kg, and the final comprehensive error is about 1 Kg. The precision of the large-tonnage casting machine cannot be improved continuously;
③ And (5) visual quantification, and judging whether the casting is full or not through the molten iron change characteristics in the casting process. Such as a larger diameter of the cross-section of the liquid surface in the pouring cup. However, the casting speed is too high, and the upper part of the liquid surface is also caused, so that the section is enlarged, and the casting speed is unreliable and can only be used as supplementary judgment of weighing;
The requirement of the large-tonnage casting machine for improving the quantitative casting precision cannot be met.
Disclosure of Invention
The invention aims to provide a quantitative constant-speed pouring control method for molten iron of a pouring machine, so as to solve the problems in the prior art.
In order to achieve the above purpose, the present invention provides the following technical solutions: the quantitative constant-speed pouring control method for molten iron of a pouring machine comprises the following steps:
S1, determining the volume of a molten iron cavity in a casting machine, and carrying out three-dimensional modeling on the molten iron cavity;
S2, equally angularly dividing the modeled molten iron cavity according to the molten iron water outlet point;
S3, slicing the split points in micro-sections after splitting;
s4, performing external excision on the model, and inquiring the weight of the rest sliced entities to calculate the weight per degree;
S5, summarizing the calculated weight data of each degree into a chart;
s6, establishing a database, and making corresponding data blocks in the database according to the chart data;
S7, writing the data obtained in the chart into a controller data block;
s8, controlling quantitative constant-speed pouring of the molten iron through a controller.
Preferably, the theoretical basis of the quantification is as follows:
Q＝α*ρ Corner angle ；
wherein Q is the poured molten iron quantity, alpha is the ladle tilting angle, rho Corner angle is the ladle angular density, and the unit of the ladle angular density is kg/°.
Preferably, the ladle tilting angle is calculated by a tilting servomotor.
Preferably, the differential casting quantity is calculated according to real-time data in the running process, and the result is integrated into the total real-time casting quantity.
Preferably, the calculation formula of the pouring amount is as follows:
ρ Real time ＝(ρ Upper part -ρ Lower part(s) )/α Dividing into portions *(α Currently, the method is that -α Upper part )+ρ Upper part 。
preferably, ρ Real time in the above formula is the real-time angular density, ρ Upper part is the back-end angular density database data, and ρ Lower part(s) is the front-end angular density database data.
Preferably, α Dividing into portions is a portioning angle, α Currently, the method is that is a real-time inclination angle, and α Upper part is a front portioning inclination angle in the above formula.
Preferably, the calculation formula of the differential pouring quantity is as follows:
Q Micro-scale ＝α Micro-scale *ρ Real time 。
preferably, in the above formula, Q Micro-scale is a micro-angle pouring amount, α Micro-scale is a tilting micro-angle, and the calculation formula of the total pouring amount is Q Total (S) ＝Q Micro-scale 1+Q Micro-scale 2+Q Micro-scale 3+Q Micro-scale 4 … ….
Preferably, the casting speed control theory basis comprises: v Real time ＝V Setting up /ρ Real time ;
In the formula, V Real time is a required real-time target speed (unit is degree/s), V Setting up is a set pouring speed (unit is Kg/s), rho Real time is a real-time angular density under the forward tilting angle, the required tilting speed Kg/s is calculated according to database data, and finally, the required tilting speed Kg/s is converted into a motor rotating speed to be transmitted to a servo motor, and the stable pouring speed is controlled.
The invention provides a quantitative constant-speed pouring control method for molten iron of a pouring machine. The beneficial effects are as follows:
(1) According to the invention, a data table is obtained through differentiation of a pouring ladle mathematical model, a program database is established according to the data table, real-time angular density is calculated through database data, micro-variable pouring weight is obtained through multiplication of a tilting micro-variable angle and the real-time angular density, and pouring quantity is obtained through pouring micro-integration, so that accurate quantitative pouring is realized, the pouring precision is about 0.2Kg, and high-precision quantitative pouring is realized.
(2) According to the invention, the real-time pouring angle speed is calculated according to the database data, and finally converted into the motor rotating speed to be fed to the servo motor, so that the stable pouring speed is controlled, and the high-precision constant-speed pouring is realized.
(3) According to the invention, various data are input into the database, and the numerical control system of the casting machine controls the casting quantity according to the database data, so that the casting quantity is more convenient, and the manual operation is simple, convenient and efficient without the need of human eyes and manual operation.
Drawings
FIG. 1 is a schematic view of a casting ladle of the present invention;
FIG. 2 is a block diagram of a molten iron vessel in a ladle of the present invention;
FIG. 3 is a schematic view of the invention in equal angular divisions of a molten iron vessel;
FIG. 4 is a schematic view of a portion-wise microtome according to the present invention;
FIG. 5 is a schematic view of a portion-wise microtome according to the present invention;
FIG. 6 is a schematic view of a portion-wise microtome according to the present invention;
FIG. 7 is a data summary table of the iron and water fraction of the present invention;
FIG. 8 is a line drawing of molten iron portion data according to the present invention;
FIG. 9 is a schematic diagram of data blocks in a database according to the present invention;
FIG. 10 is a schematic diagram of a configuration input window according to the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments.
Examples of the embodiments are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements throughout or elements having like or similar functionality. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
As shown in fig. 1 to 10, the present invention provides a technical solution: the quantitative constant-speed pouring control method for molten iron of a pouring machine comprises the following steps: s1, determining the volume of a molten iron cavity in a casting machine, and carrying out three-dimensional modeling on the molten iron cavity;
S2, equally angularly dividing the modeled molten iron cavity according to the molten iron water outlet point, for example, 0.9 degree is divided into one part, and an included angle between each line in the graph 3 is 0.9 degree;
S3, after the division, the trace sections of the division points are shown in the figures 4-6, and for example, each line is offset by 0.01 DEG to form a cutting area;
S4, performing external excision on the model along the excision surface area, and inquiring the weight of the rest sliced entities to calculate the weight of each degree;
S5, integrating the calculated weight data of each degree into a graph, as shown in fig. 7 and 8;
S6, establishing a database, and making corresponding data blocks in the database according to the chart data, as shown in FIG. 9;
S7, writing the data obtained in the chart into a controller data block as shown in FIG. 10;
s8, controlling quantitative constant-speed pouring of the molten iron through a controller.
The theoretical basis of quantification is as follows:
Q＝α*ρ Corner angle ；
Wherein Q is the poured molten iron quantity, alpha is the ladle tilting angle, rho Corner angle is the ladle angular density, the unit of the ladle angular density is kg/DEG, and the ladle tilting angle is calculated by a tilting servo motor.
Calculating differential pouring quantity according to real-time data in the operation process, and integrating the result into real-time pouring total quantity, wherein the calculating formula of the pouring quantity is as follows:
ρ Real time ＝(ρ Upper part -ρ Lower part(s) )/α Dividing into portions *(α Currently, the method is that -α Upper part )+ρ Upper part , ρ Real time is the real-time angular density, ρ Upper part is the back-end angular density database data, ρ Lower part(s) is the front-end angular density database data, α Dividing into portions is the split angle, a Currently, the method is that is the real-time tilt angle, and α Upper part is the front-end tilt angle;
The calculation formula of the differential pouring quantity is as follows:
Q Micro-scale ＝α Micro-scale /ρ Real time , wherein Q Micro-scale is micro-angle pouring quantity, alpha Micro-scale is tilting micro-angle, and the calculation formula of total pouring quantity is as follows; q Total (S) ＝Q Micro-scale 1+Q Micro-scale 2+Q Micro-scale 3+Q Micro-scale 4 … …
The casting speed control theory basis comprises: v Real time ＝V Setting up /ρ Real time , wherein V Real time is a required real-time target speed (unit is DEG/s), V Setting up is a set pouring speed (unit is kg/s), and ρ Real time is a real-time angular density at a forward tilting angle.
In view of the foregoing, it will be appreciated that while embodiments of the invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations may be made hereto without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims (1)
1. The quantitative constant-speed pouring control method for the molten iron of the pouring machine is characterized by comprising the following steps of:
S1, determining the volume of a molten iron cavity in a casting machine, and carrying out three-dimensional modeling on the molten iron cavity;
S2, equally angularly dividing the modeled molten iron cavity according to the molten iron water outlet point;
S3, slicing the split points in micro-sections after splitting;
s4, performing external excision on the model, and inquiring the weight of the rest sliced entities to calculate the weight per degree;
S5, summarizing the calculated weight data of each degree into a chart;
s6, establishing a database, and making corresponding data blocks in the database according to the chart data;
S7, writing the data obtained in the chart into a controller data block;
S8, controlling quantitative constant-speed pouring of molten iron through a controller;
the theoretical basis of quantification is as follows:
Q＝α*ρ Corner angle ；
Wherein Q is the poured molten iron amount, alpha is the ladle tilting angle, rho Corner angle is the ladle angular density, and the unit of the ladle angular density is kg/°;
The ladle tilting angle is calculated by a tilting servomotor.
Calculating differential pouring quantity according to real-time data in the running process, and integrating the result into the total real-time pouring quantity;
The calculation formula of the casting quantity is as follows:
ρ Real time ＝(ρ Upper part -ρ Lower part(s) )/α Dividing into portions *(α Currently, the method is that -α Upper part )+ρ Upper part ；
in the formula, ρ Real time is real-time angular density, ρ Upper part is back part angular density database data, and ρ Lower part(s) is front part angular density database data;
In the formula, alpha Dividing into portions is a dividing angle, alpha Currently, the method is that is a real-time inclination angle, and alpha Upper part is a front dividing inclination angle;
The calculation formula of the differential pouring quantity is as follows:
Q Micro-scale ＝α Micro-scale *ρ Real time ；
Q Micro-scale in the formula is micro-angle pouring quantity, alpha Micro-scale is tilting micro-angle, and the calculation formula of total pouring quantity is Q Total (S) ＝Q Micro-scale 1+Q Micro-scale 2+Q Micro-scale 3+Q Micro-scale 4 … …;
the casting speed control theory basis comprises: v Real time ＝V Setting up /ρ Real time ;
In the formula, V Real time is a required real-time target speed (unit is DEG/s), V Setting up is a set pouring speed (unit is kg/s), and ρ Real time is a real-time angular density at a forward tilting angle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211158884.4A CN115430828B (en) | 2022-09-22 | 2022-09-22 | Quantitative constant-speed pouring control method for molten iron of pouring machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211158884.4A CN115430828B (en) | 2022-09-22 | 2022-09-22 | Quantitative constant-speed pouring control method for molten iron of pouring machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115430828A CN115430828A (en) | 2022-12-06 |
| CN115430828B true CN115430828B (en) | 2024-07-23 |
Family
ID=84248891
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211158884.4A Active CN115430828B (en) | 2022-09-22 | 2022-09-22 | Quantitative constant-speed pouring control method for molten iron of pouring machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115430828B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2303145A1 (en) * | 1997-09-03 | 1999-03-11 | Mse Technology Applications, Inc. | Particulate field distributions in centrifugally cast metal matrix composites |
| CN105798253A (en) * | 2016-06-06 | 2016-07-27 | 重庆大学 | Special-shaped blank continuous casting secondary-cooling roll gap adjustment method |
Family Cites Families (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1192373A (en) * | 1981-12-14 | 1985-08-27 | Robert W. Hazelett | Method and system for shaping the casting region in a twin-belt continuous casting machine for improving heat transfer and product uniformity and enhanced machine performance |
| DE69403950T3 (en) * | 1993-01-15 | 2005-03-10 | Abb Inc., St.Laurent | AC magnetic stirring for continuous casting of metals |
| JP3537012B2 (en) * | 1996-03-05 | 2004-06-14 | 日立金属株式会社 | Automatic pouring control method |
| JPH1094870A (en) * | 1996-09-26 | 1998-04-14 | Hitachi Metals Ltd | Method for automatically pouring molten metal |
| US7943084B1 (en) * | 2007-05-23 | 2011-05-17 | The United States Of America As Represented By The Secretary Of The Navy | Metal powders with improved flowability |
| JP5116722B2 (en) * | 2009-04-28 | 2013-01-09 | 新東工業株式会社 | Ladle tilting automatic pouring method, ladle tilt control system, and storage medium storing ladle tilt control program |
| JP6330542B2 (en) * | 2014-07-17 | 2018-05-30 | 新日鐵住金株式会社 | Manufacturing method of continuous cast slab |
| US10670678B2 (en) * | 2015-06-15 | 2020-06-02 | Koninklijke Philips N.V. | MR imaging using stack-of stars acquisition |
| CN106475543A (en) * | 2016-11-16 | 2017-03-08 | 北京科技大学 | A kind of continuous casting billet cutting process scale compensation method |
| CN207606257U (en) * | 2017-10-30 | 2018-07-13 | 天津市津和双金属线材有限公司 | A kind of cast bar copper wheel uniformly to cool |
| WO2020257307A1 (en) * | 2019-06-21 | 2020-12-24 | Pcms Holdings, Inc. | Method for enhancing the image of autostereoscopic 3d displays based on angular filtering |
| EP3819873A1 (en) * | 2019-11-05 | 2021-05-12 | Koninklijke Philips N.V. | An image synthesis system and method therefor |
| CN111151733A (en) * | 2020-01-16 | 2020-05-15 | 青岛力晨新材料科技有限公司 | Stainless steel/carbon steel composite board gating system and production system |
| CN112131709B (en) * | 2020-08-25 | 2024-04-19 | 山东大学 | Joint rock mass mechanical simulation method and system based on near field dynamics constitutive model |
| CN113478791B (en) * | 2021-07-16 | 2022-07-29 | 合肥工业大学 | Preparation method of woven gas cylinder and woven gas cylinder |
| CN217166470U (en) * | 2021-12-30 | 2022-08-12 | 贵州华清新材料科技有限公司 | Aluminum water dumping device |
-
2022
- 2022-09-22 CN CN202211158884.4A patent/CN115430828B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2303145A1 (en) * | 1997-09-03 | 1999-03-11 | Mse Technology Applications, Inc. | Particulate field distributions in centrifugally cast metal matrix composites |
| CN105798253A (en) * | 2016-06-06 | 2016-07-27 | 重庆大学 | Special-shaped blank continuous casting secondary-cooling roll gap adjustment method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115430828A (en) | 2022-12-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108705071B (en) | Alloy liquid pouring method capable of automatically controlling flow speed | |
| CN101454100B (en) | Automatic pouring method and storage medium storing ladle tilting control program | |
| JP2002502733A (en) | Automated molding technology for thermoplastic injection molding | |
| CN104999043B (en) | Online measuring device and method for opening degree of sliding nozzle of continuous casting ladle | |
| CN105108095B (en) | The mixed method pouring base position and length end to end is determined based on continuous measurement of molten steel temperature | |
| CN104070513A (en) | Method for precision lineation of thin-wall special-shaped cast cabin | |
| CN115430828B (en) | Quantitative constant-speed pouring control method for molten iron of pouring machine | |
| CN106077553A (en) | Weighing method is determined in continuous casting steel billet weight Based Intelligent Control diced system and continuous casting steel billet cutting | |
| CN102764863B (en) | Test device for performing simulative test on continuous casting mold vibration technological process | |
| JPH0647620A (en) | Processing method for gears | |
| CN106694863B (en) | Molten steel pouring control method and device | |
| CN107272595B (en) | Low-speed diesel engine base Hough method for processing surface | |
| CN102059332B (en) | System for realizing life cycle model of plate blank in basic automation | |
| JP5675027B2 (en) | Automatic pouring method and automatic pouring apparatus | |
| CN109352372A (en) | A kind of quick-adjustsing method of realization part benchmark | |
| CN211539461U (en) | System for on-line measuring mouth of a river blocks up | |
| CN202726000U (en) | Simulation detecting and testing device for vibrating technical process of continuous casting crystallizer | |
| JP7218702B2 (en) | Machine tools, measuring methods and computer programs | |
| CN115178730B (en) | Quantitative pouring device and method for copper alloy intermediate frequency furnace | |
| US8020605B2 (en) | Continuous steel slab caster and methods using same | |
| US20080179036A1 (en) | Continuous steel slab caster and methods using same | |
| CN214263846U (en) | Die-casting die capable of eliminating shrinkage air holes | |
| JP2774727B2 (en) | Automatic pouring equipment in casting equipment | |
| CN112207246B (en) | Method for measuring solidification end point of square billet | |
| CN210648416U (en) | Covering slag thickness measuring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |