CN112484814A - Electronic liquid level meter - Google Patents
Electronic liquid level meter Download PDFInfo
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- CN112484814A CN112484814A CN201910855256.3A CN201910855256A CN112484814A CN 112484814 A CN112484814 A CN 112484814A CN 201910855256 A CN201910855256 A CN 201910855256A CN 112484814 A CN112484814 A CN 112484814A
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- 239000007788 liquid Substances 0.000 title abstract description 33
- 238000005259 measurement Methods 0.000 claims description 17
- 230000001681 protective effect Effects 0.000 claims description 6
- 238000003860 storage Methods 0.000 claims description 6
- 238000004891 communication Methods 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 3
- 239000003566 sealing material Substances 0.000 claims description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 20
- 229910052742 iron Inorganic materials 0.000 abstract description 10
- 230000032683 aging Effects 0.000 abstract description 7
- 230000035882 stress Effects 0.000 abstract description 7
- 230000008859 change Effects 0.000 description 12
- 235000014676 Phragmites communis Nutrition 0.000 description 5
- 230000009471 action Effects 0.000 description 5
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/30—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats
- G01F23/40—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats using bands or wires as transmission elements
- G01F23/44—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats using bands or wires as transmission elements using electrically actuated indicating means
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Level Indicators Using A Float (AREA)
Abstract
The invention discloses an electronic liquid level meter, which comprises a measuring circuit arranged in a shell; a sleeve disposed outside the housing; a communicating pipe is arranged between the upper end of the sleeve and the tank body as a measuring object; a current converter for converting a current of the measuring circuit into an electrical signal; the measuring circuit comprises a power interface, a plurality of Insulated Gate Bipolar Transistors (IGBT) and a resistor string; the positive electrode of the power supply interface is respectively connected with the measuring resistor at the head end of the resistor string and the collector electrode of each IGBT; the emitting electrodes of the IGBTs are respectively connected between the resistors; the negative electrode of the power supply interface is connected with the protection resistor; the grid contact of each IGBT is out of the shell; a float contact for making the corresponding IGBT conductive by contacting with the pole contact is arranged in the sleeve; and the connecting line connected with the float contact is connected with the float through the communicating pipe. The invention does not have the problem of stress aging of the iron sheet, thereby avoiding the fault caused by the stress aging of the iron sheet and effectively prolonging the service life of the electronic liquid level meter.
Description
Technical Field
The invention relates to the field of measurement, in particular to an electronic liquid level meter.
Background
In storage devices required for industrial production such as storage tanks and buffer tanks, level gauges are often used to indicate the level information of materials therein for other work related thereto.
In the prior art, the working principle of the liquid level meter which is often used comprises: the circuit is switched on by the combination of the reed switch and the magnet in a way that the reed switch is attracted by the magnetic force of the magnet, so that the transmission of electric signals is realized. Specifically, in the working process of the liquid level meter, a floater containing a magnet can rise or fall along with the change of the liquid level, in the rising or falling process of the floater, the reed pipe iron sheet can attract the magnet at the corresponding position, so that different attraction positions form different circuit conduction modes, the current in a loop is controlled by the number of series resistors corresponding to the conduction circuits, and different transmission signals are generated to represent the liquid level information of a measurement object.
The inventor finds that the prior art has at least the following defects through research:
the mechanical action that the iron sheet in the reed pipe is attracted by magnetic force is easy to generate stress aging in the using process, and further faults such as improper attraction or disconnection and the like are generated, even the reed pipe is damaged; therefore, the service life of the prior art level gauge is too short.
Disclosure of Invention
The invention mainly aims to improve the failure probability of the liquid level meter and prolong the service life of the liquid level meter.
In order to achieve the purpose, the invention adopts the technical scheme that:
the invention discloses an electronic liquid level meter, comprising: a measurement circuit disposed within the housing; a sleeve disposed outside the housing; a communicating pipe is arranged between the upper end of the sleeve and the tank body as a measuring object; a current converter for converting the current of the measuring circuit into an electrical signal;
the measuring circuit comprises a power interface, a plurality of Insulated Gate Bipolar Transistors (IGBT) and a resistor string which is connected with a plurality of measuring resistors and a protective resistor in series; the protection resistor is arranged at the tail end of the resistor string; the positive electrode of the power supply interface is respectively connected with the measuring resistor at the head end of the resistor string and the collector electrode of each IGBT; the emitting electrodes of the IGBTs are respectively connected between the resistors in the resistor string; the negative electrode of the power supply interface is connected with the protection resistor;
grid contacts of the IGBTs penetrate through the shell and are sequentially and equidistantly arranged at positions, corresponding to the sleeve, outside the shell; a float contact for turning on the corresponding IGBT by contacting with the gate contact is provided in the sleeve; the other end of the connecting wire fixedly connected with the float contact is connected with a float arranged in the tank body through the communicating pipe.
Preferably, in the present invention, the number of the measuring resistors includes 6 to 15.
Preferably, in the present invention, the voltage of the power interface is 15V to 36V.
Preferably, in the present invention, pulleys adapted to the connection line are disposed at two ends or one end of the communication pipe.
Preferably, in the present invention, the float contact is provided with a ground circuit.
Preferably, in the present invention, the ground circuit is provided to the connection line.
Preferably, in the present invention, the measurement object includes a storage tank or a buffer tank used in a petrochemical enterprise.
Preferably, in the present invention, the communication tube further includes a soft sealing material for sealing.
Preferably, in the present invention, among the gate contacts of the IGBTs, the gate contact of the IGBT corresponding to the measuring resistance at the head end of the resistor string is highest at the position of the bushing.
Advantageous effects
The electronic liquid level meter comprises a shell and a sleeve, wherein a measuring circuit in the shell comprises a resistor string and a plurality of IGBTs, grid contacts of the IGBTs penetrate through the shell and are sequentially and equidistantly arranged outside the shell, and then float contacts capable of moving up and down in the sleeve can be respectively communicated with the grid contacts of the IGBTs according to unknown differences to excite the corresponding IGBTs to be communicated. Due to the conduction of different IGBTs, the current in the measuring circuit can flow through different numbers of measuring resistors, so that the current value in the measuring circuit is correspondingly changed, namely, the current value in the measuring circuit is correspondingly changed along with the change of the upper position and the lower position of the float contact and respectively contacts with the grid contacts of different IGBTs; that is, in the present invention, the value of the current in the measurement circuit can be indicative of the position of the float contact in the sleeve. Then, in the invention, the float contact is connected with the float arranged on the tank body as the measuring object through the connecting wire, so that when the height of the float changes along with the change of the liquid level in the tank body, the float contact is driven to move up and down in the sleeve, and the corresponding change of the current value in the measuring circuit is further caused.
Therefore, the electronic liquid level meter does not need the iron sheet to control the number of the resistors in the measuring circuit through mechanical action under the action of magnetic force, so that the problem of stress aging of the iron sheet does not exist, further faults of attraction or improper disconnection and the like caused by the stress aging of the iron sheet are avoided, and the service life of the electronic liquid level meter is effectively prolonged.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood and to make the technical means implementable in accordance with the contents of the description, and to make the above and other objects, technical features, and advantages of the present invention more comprehensible, one or more preferred embodiments are described below in detail with reference to the accompanying drawings.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic structural view of an electronic level gauge according to the present invention;
FIG. 2 is a schematic structural diagram of a measurement circuit in the electronic level gauge of the present invention.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
Spatially relative terms, such as "below," "lower," "upper," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the figures. For example, if the items in the figures are turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the elements or features. Thus, the exemplary term "below" can encompass both an orientation of below and above. The article may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.
In this document, the terms "first", "second", etc. are used to distinguish two different elements or portions, and are not used to define a particular position or relative relationship. In other words, the terms "first," "second," and the like may also be interchanged with one another in some embodiments.
In order to reduce the failure probability of the liquid level meter and prolong the service life of the liquid level meter, referring to fig. 1 and 2, an embodiment of the invention provides an electronic liquid level meter, which comprises: a measurement circuit 02 provided in the housing 01; a sleeve 03 disposed outside the housing 01; a communicating pipe 05 is arranged between the upper end of the sleeve 03 and the tank 04 as a measurement object; a current converter 06 for converting the current of the measuring circuit 02 into an electrical signal;
the measuring circuit 02 comprises a power interface 21, a plurality of IGBTs 22, and a resistor string connected in series with a plurality of measuring resistors 23 and a protection resistor 24; the protection resistor 24 is arranged at the tail end of the resistor string; the positive electrode of the power interface 21 is connected to the measuring resistor 23 at the head end of the resistor string and the collector of each IGBT 22; the emitters of the IGBTs 22 are respectively connected between the resistors (including the measuring resistor 23 and the protection resistor 24) in the resistor string; the negative electrode of the power supply interface 42 is connected with the protection resistor 24;
gate contacts of the IGBTs 22 penetrate through the shell 01 and are sequentially and equidistantly arranged at positions corresponding to the sleeve 03 outside the shell 01; a float contact 07 for turning on the corresponding IGBT by contacting the gate contact is provided in the bushing 03; the other end of the connecting wire 08 fixedly connected with the float contact 07 is connected with a float 09 arranged in the tank 04 through the communicating pipe 05.
In practical applications, the number of the measuring resistors in the embodiment of the present invention may be set accordingly according to requirements of different accuracies or different ranges, preferably, the number of the measuring resistors may include 6 to 15, and the following describes the operating principle of the embodiment of the present invention with the number of the measuring resistors 23 being 6:
the 6 measuring resistors 23 (named R1 to R6, respectively) and the other protective resistor 24 connected in series in the measuring circuit 02 form a resistor string, and emitters of an IGBT22 are connected between the measuring resistors 23 and between the protective resistor 24 and the adjacent measuring resistor 23 (R6), so that each measuring resistor 23 corresponds to an IGBT22 (named G1 to G6, respectively).
The specific connection mode of the measurement circuit 02 is as follows: the resistor string is provided with R1 in the measuring resistor 23 at the head end and a protective resistor 24 (R7) at the tail end, and firstly, the anode of the power interface is connected with R1 in the measuring resistor 23 to supply power to the whole resistor string; next, an emitter of G1 in the IGBT22 is connected between R1 and R2, an emitter of G2 is connected between R2 and R3, an emitter of G3 is connected between R3 and R4, an emitter of G4 is connected between R4 and R5, an emitter of G5 is connected between R5 and R6, and an emitter of G6 is connected between R6 and the protection resistor 24; next, the collector of each IGBT22 in G1 to G6 is connected to the positive electrode of the power interface, and the gate of each IGBT22 in G1 to G6 penetrates through the housing 01 and forms a gate contact on the outer wall of the housing 01; the gate contacts are arranged on the outer wall of the shell 01 sequentially and equidistantly according to the sequence of the IGBTs 22 from G1 to G6; sleeves 03 are arranged at positions corresponding to the gate contacts, and the sleeves 03 are used for accommodating the float contacts 07, so that the float contacts 07 can be respectively contacted with the gate contacts when moving up and down in the sleeves 03, and accordingly, the IGBTs 22 corresponding to the float contacts 07 contacted with the float contacts are respectively conducted, specifically, when the float contacts 07 are contacted with the gate contacts of G1, G1 is in a conducting state, when the float contacts 07 are contacted with the gate contacts of G2, G2 is in a conducting state, when the float contacts 07 are contacted with the gate contacts of G3, G3 is in a conducting state, and the like, according to the position of the float contacts 07 in the sleeves 02, the IGBTs 22 can be respectively conducted.
Next, as can be seen from fig. 2, the turn-on of different IGBTs 22 causes a difference in the amount of resistance through which the current flows in the measuring circuit 02, and specifically, when the float contact 07 contacts the gate contact of G1, G1 will be in the on state (G2 to G6 are in the off state), at this time, the current in the measuring circuit 02 will not pass through R1 in the measuring resistance 23 at the head end in the resistance string, and at this time, the total resistance value of the measuring circuit 02 is (R2 + R3+ R4+ R5+ R6+ R7); when the float contact 07 contacts the gate contact of G2, G2 will be in a conducting state (G3 to G6 are in an open state), and at this time, the current in the measurement circuit 02 will not pass through R1 and R2, and the total resistance value of the measurement circuit 02 is (R3 + R4+ R5+ R6+ R7); by analogy, depending on the position of the float contact 07 in the bushing 02, a change in the total resistance of the measuring circuit 02 may result, so that a corresponding change in the current of the measuring circuit 02 may also occur.
The position of the float contact 07 is linked with the position of the float 09 arranged in the tank body, specifically, the float contact 07 arranged in the sleeve 03 and the float 09 arranged in the tank body are connected together through a connecting line by a communicating pipe 05, and the float 09 moves up and down along with the liquid level change of the liquid storage in the tank body 04, so that the float contact 07 is driven to move up and down in the sleeve 03, and the current of the measuring circuit 02 is caused to change correspondingly; the current converter 06 in the embodiment of the present invention may generate liquid level information for characterizing a current liquid level of the stored liquid in the tank 04 according to a current change of the measurement circuit 02.
Taking fig. 2 as an example, among the gate contacts of the IGBTs 22, the gate contact (G1) of the IGBT22 corresponding to the measuring resistor (R1) at the head end of the resistor string is highest at the position of the bushing; namely, G1 to G6 are arranged in this order from top to bottom. When no liquid is stored in the tank 04, the position of the floater 09 is at the lowest point in the tank 04, the floater contact 07 is driven to be at the highest position in the sleeve 03, at the moment, the floater contact 07 does not contact any grid contact of the IGBT22, and along with the rise of the liquid level in the tank 04, the floater contact 07 is sequentially communicated with the grid contacts G1 to G6 one by one, so that the IGBTs corresponding to the grid contacts are respectively conducted. When the liquid storage in the tank 04 is full, the position of the floater 09 reaches the highest point, the position of the floater contact 07 reaches the lowest point, the grid contact of G6 is communicated, only the protective resistor 24 (R7) in the measuring circuit 02 passes through the current, and the current value of the measuring circuit 02 is the maximum at the moment.
In the embodiment of the present invention, by providing the protection resistor 24 (R7), the failure of the measurement circuit 02 due to a short circuit can be avoided.
In practical applications, in order to be suitable for controlling the on and off of the IGBT22, it is preferable that the voltage selection range of the power interface 21 in the embodiment of the present invention is set to 15V to 36V. In addition, in order to reduce friction between the float contact and the float 09, in the present invention, both ends or one end of the communication pipe 05 may be further provided with pulleys (not shown in the drawings) adapted to the connection line 08.
In order to enable the corresponding IGBT to be turned on by the floating contact 07 and the gate contact, the floating contact in the embodiment of the present invention may be further provided with a ground circuit (not shown in the figure). In practical applications, the grounding circuit can be provided on the connecting line. Further, in order to prevent liquid or volatile gas in the tank 04 from entering the sleeve 03 to affect the normal operation of the electronic liquid level meter, in the embodiment of the present invention, a soft sealing material for sealing may be filled in the communicating pipe 05.
In summary, the electronic liquid level meter in the embodiment of the present invention includes a housing and a bushing, wherein a measurement circuit in the housing includes a resistor string and a plurality of IGBTs, gate contacts of the IGBTs penetrate through the housing, and after the gate contacts are sequentially and equidistantly disposed outside the housing, float contacts capable of moving up and down in the bushing may respectively communicate with the gate contacts of the IGBTs to excite the corresponding IGBTs to conduct according to unknown differences. Due to the conduction of different IGBTs, the current in the measuring circuit can flow through different numbers of measuring resistors, so that the current value in the measuring circuit is correspondingly changed, namely, the current value in the measuring circuit is correspondingly changed along with the change of the upper position and the lower position of the float contact and respectively contacts with the grid contacts of different IGBTs; that is, in the present invention, the value of the current in the measurement circuit can be indicative of the position of the float contact in the sleeve. Then, in the invention, the float contact is connected with the float arranged on the tank body as the measuring object through the connecting wire, so that when the height of the float changes along with the change of the liquid level in the tank body, the float contact is driven to move up and down in the sleeve, and the corresponding change of the current value in the measuring circuit is further caused.
Therefore, the electronic liquid level meter does not need the iron sheet to perform mechanical action under the action of magnetic force to control the number of the resistors in the measuring circuit, so that the problem of stress aging of the iron sheet does not exist, further faults of attraction or improper disconnection and the like caused by the stress aging of the iron sheet are avoided, and the service life of the electronic liquid level meter is effectively prolonged.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. Any simple modifications, equivalent changes and modifications made to the above exemplary embodiments shall fall within the scope of the present invention.
Claims (9)
1. An electronic level gauge, comprising: a measurement circuit disposed within the housing; a sleeve disposed outside the housing; a communicating pipe is arranged between the upper end of the sleeve and the tank body as a measuring object; a current converter for converting the current of the measuring circuit into an electrical signal;
the measuring circuit comprises a power interface, a plurality of Insulated Gate Bipolar Transistors (IGBT) and a resistor string which is connected with a plurality of measuring resistors and a protective resistor in series; the protection resistor is arranged at the tail end of the resistor string; the positive electrode of the power supply interface is respectively connected with the measuring resistor at the head end of the resistor string and the collector electrode of each IGBT; the emitting electrodes of the IGBTs are respectively connected between the resistors in the resistor string; the negative electrode of the power supply interface is connected with the protection resistor;
grid contacts of the IGBTs penetrate through the shell and are sequentially and equidistantly arranged at positions, corresponding to the sleeve, outside the shell; a float contact for turning on the corresponding IGBT by contacting with the gate contact is provided in the sleeve; the other end of the connecting wire fixedly connected with the float contact is connected with a float arranged in the tank body through the communicating pipe.
2. The electronic level gauge of claim 1, wherein the number of measuring resistors comprises 6 to 15.
3. The electronic level gauge of claim 1, wherein the voltage of the power interface is 15V to 36V.
4. The electronic level gauge according to claim 1, wherein a pulley adapted to the connection line is disposed at one or both ends of the connection pipe.
5. The electronic level gauge of claim 1, wherein the float contact is provided with a ground circuit.
6. The electronic level gauge of claim 5, wherein the ground circuit is disposed at the connecting wire.
7. The electronic level gauge of claim 1, wherein the measurement object comprises a storage tank or a buffer tank used by a petrochemical enterprise.
8. The electronic level gauge of claim 1, further comprising a soft sealing material within the communication tube for sealing.
9. The electronic level gauge of claim 1, wherein a gate contact of the IGBT corresponding to the measuring resistance at the head end of the resistor string is highest among gate contacts of the IGBTs at a position of the bushing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910855256.3A CN112484814A (en) | 2019-09-11 | 2019-09-11 | Electronic liquid level meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910855256.3A CN112484814A (en) | 2019-09-11 | 2019-09-11 | Electronic liquid level meter |
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| Publication Number | Publication Date |
|---|---|
| CN112484814A true CN112484814A (en) | 2021-03-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910855256.3A Pending CN112484814A (en) | 2019-09-11 | 2019-09-11 | Electronic liquid level meter |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1220270A (en) * | 1967-10-28 | 1971-01-27 | Zanussi A Spa Industrie | An electrical circuit arrangement for controlling the quantity of liquid in a tank |
| CN103616056A (en) * | 2013-12-11 | 2014-03-05 | 何杰恩 | Multipoint liquid level detection circuit |
| CN108195442A (en) * | 2018-01-24 | 2018-06-22 | 北京麦格智能科技有限公司 | TMR liquid level sensors |
| CN208012711U (en) * | 2018-02-01 | 2018-10-26 | 荣盛达（无锡）能源有限公司 | A kind of voltage-type Floating Ball Liquid Level device |
| CN109060076A (en) * | 2018-08-02 | 2018-12-21 | 重庆川仪自动化股份有限公司 | Resistance sensor and measuring system |
-
2019
- 2019-09-11 CN CN201910855256.3A patent/CN112484814A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1220270A (en) * | 1967-10-28 | 1971-01-27 | Zanussi A Spa Industrie | An electrical circuit arrangement for controlling the quantity of liquid in a tank |
| CN103616056A (en) * | 2013-12-11 | 2014-03-05 | 何杰恩 | Multipoint liquid level detection circuit |
| CN108195442A (en) * | 2018-01-24 | 2018-06-22 | 北京麦格智能科技有限公司 | TMR liquid level sensors |
| CN208012711U (en) * | 2018-02-01 | 2018-10-26 | 荣盛达（无锡）能源有限公司 | A kind of voltage-type Floating Ball Liquid Level device |
| CN109060076A (en) * | 2018-08-02 | 2018-12-21 | 重庆川仪自动化股份有限公司 | Resistance sensor and measuring system |
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Effective date of registration: 20240322 Address after: 100728 No. 22 North Main Street, Chaoyang District, Beijing, Chaoyangmen Applicant after: CHINA PETROLEUM & CHEMICAL Corp. Country or region after: China Applicant after: Sinopec (Dalian) Petrochemical Research Institute Co.,Ltd. Address before: 100728 No. 22 North Main Street, Chaoyang District, Beijing, Chaoyangmen Applicant before: CHINA PETROLEUM & CHEMICAL Corp. Country or region before: China Applicant before: DALIAN RESEARCH INSTITUTE OF PETROLEUM AND PETROCHEMICALS, SINOPEC Corp. |