CN114178320A - Stainless steel rolling oil injection control system and energy-saving method using same - Google Patents
Stainless steel rolling oil injection control system and energy-saving method using same Download PDFInfo
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- CN114178320A CN114178320A CN202111526496.2A CN202111526496A CN114178320A CN 114178320 A CN114178320 A CN 114178320A CN 202111526496 A CN202111526496 A CN 202111526496A CN 114178320 A CN114178320 A CN 114178320A
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- oil
- valve
- oil pump
- main pipeline
- stainless steel
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- 238000002347 injection Methods 0.000 title claims abstract description 42
- 239000007924 injection Substances 0.000 title claims abstract description 42
- 239000010731 rolling oil Substances 0.000 title claims abstract description 40
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 25
- 239000010935 stainless steel Substances 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000003921 oil Substances 0.000 claims abstract description 73
- 239000007921 spray Substances 0.000 claims description 10
- 239000007788 liquid Substances 0.000 claims description 4
- 238000004134 energy conservation Methods 0.000 abstract description 6
- 239000002699 waste material Substances 0.000 abstract description 2
- 238000005096 rolling process Methods 0.000 description 6
- 241001370313 Alepes vari Species 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005097 cold rolling Methods 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002441 reversible effect Effects 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000009530 blood pressure measurement Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0239—Lubricating
- B21B45/0245—Lubricating devices
- B21B45/0248—Lubricating devices using liquid lubricants, e.g. for sections, for tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B2037/002—Mass flow control
-
- 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
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Abstract
The invention relates to a stainless steel rolling oil injection control system, which comprises: the oil tank is used for storing rolling oil; one end of the main pipeline is connected with an injection head; the input end of each oil pump is communicated with the oil tank, and the output end of each oil pump is communicated with the other end of the main pipeline; each motor is connected with one of the oil pumps; the method is characterized in that: at least one of the motors is a variable frequency motor, and the variable frequency motor further comprises a first valve which is arranged on the main pipeline and is used for controlling whether the main pipeline is communicated or not; one end of the bypass pipeline is communicated with the main pipeline, the other end of the bypass pipeline is communicated with the oil tank, and a second valve used for controlling whether the bypass pipeline is communicated or not is arranged on the bypass pipeline; and the control module is respectively connected with the first valve, the second valve and the motor connected with each oil pump. Also discloses an energy-saving method using the stainless steel rolling oil injection control system. The method can realize jet energy conservation, improves power surplus and energy waste, and is suitable for large popularization and use.
Description
Technical Field
The invention relates to the technical field of energy conservation of stainless steel rolling equipment, in particular to a rolling oil injection control system of a reversible twenty-high-roll stainless steel cold rolling unit and an energy conservation method using the system.
Background
The stainless steel cold rolling mill set is usually designed with a rolling oil injection system to provide mineral oil for the continuously rolled strip steel for cooling and lubricating so as to meet the higher requirements of the cold rolled stainless steel strip on the surface. The rolling oil injection system mainly comprises an oil tank, an injection pump motor unit device, a valve, a pipeline, a nozzle and the like, wherein the capacity of the injection pump motor unit is usually determined by the maximum injection quantity requirement of the rolling oil, and the injection pump motor runs at full speed and full load in the production process to ensure the maximum requirement; in actual use, the injection amount of the rolling oil is determined according to the material quality of the strip steel, the reduction deformation amount and the rolling speed, and the maximum flow is not required to be reached. Meanwhile, in the rolling process of the reversible rolling mill, a large amount of non-rolling time such as roll changing, quality inspection, up-down coiling and the like exists, and the rolling jet pump still runs at a high speed at the moment, so that the power is excessive and energy is wasted.
Disclosure of Invention
The first technical problem to be solved by the present invention is to provide a stainless steel rolling oil injection control system which is safer to use and can save energy in view of the above prior art.
The second technical problem to be solved by the present invention is to provide an energy saving method using the above stainless steel rolling oil injection control system in view of the above prior art.
The technical scheme adopted by the invention for solving the first technical problem is as follows: a stainless steel rolling oil spray control system comprising:
the oil tank is used for storing rolling oil;
the device comprises a main pipeline, a liquid level control device and a liquid level control device, wherein one end of the main pipeline is connected with an injection head;
the input end of each oil pump is communicated with the oil tank, and the output end of each oil pump is communicated with the other end of the main pipeline;
each motor is respectively connected with one of the oil pumps and is used for driving the oil pump to pump the rolling oil in the oil tank into the main pipeline for injection;
the method is characterized in that: at least one of the above-mentioned motors is inverter motor, stainless steel rolling oil sprays control system still includes:
the first valve is arranged on the main pipeline and used for controlling whether the main pipeline is conducted or not;
one end of the bypass pipeline is communicated with the main pipeline, the other end of the bypass pipeline is communicated with the oil tank, and a second valve used for controlling whether the bypass pipeline is communicated or not is arranged on the bypass pipeline; and
and the control module is respectively connected with the first valve, the second valve and the motor connected with each oil pump.
In order to realize monitoring the injection pressure, the device also comprises a pressure sensor which is arranged on the main pipeline and close to the injection head for detecting the injection pressure, and the pressure sensor is connected with the control module.
In order to realize the control of the variable frequency motors, each variable frequency motor is preferably further connected with a variable frequency power cabinet.
Preferably, still include the PLC switch board, control module is the PLC controller of locating in the PLC switch board, the PLC controller is connected with the frequency conversion power cabinet that every inverter motor is connected.
The technical scheme adopted by the invention for solving the second technical problem is as follows: an energy-saving method applying the stainless steel rolling oil injection control system is characterized in that: the method comprises the following steps:
step 1, selecting an oil pump working combination in a control module according to the requirement of jet flow, wherein the set oil pump working combination at least comprises an oil pump connected with a variable frequency motor;
step 3, converting the flow set in the jet flow demand into oil pump outlet pressure in a control module, and comparing the actual pressure measured by the received pressure sensor with the converted oil pump outlet pressure, thereby outputting a control signal to adjust the rotating speed of the variable frequency motor in the selected oil pump working combination;
and 4, controlling a variable frequency motor in the motors to run at the lowest frequency through the control module.
Compared with the prior art, the invention has the advantages that: through setting up the side pipeline to the realization is closed the main line when need not carry out the injection task, and the side pipeline is opened, and makes inverter motor with the operation of minimum frequency, thereby can furthest's assurance injection safety and energy-conservation, adjusts with inverter motor's rotational speed through the pressure measurement value of reality when spraying in addition, thereby when guaranteeing to spray the settlement flow, realizes energy-conserving purpose. Therefore, the method can realize jet energy conservation, improves the surplus power and the energy waste, and is suitable for large popularization and use.
Drawings
FIG. 1 is a schematic diagram of a stainless steel rolling oil injection control system in an embodiment of the present invention;
FIG. 2 is a schematic block diagram of a prior art stainless steel rolling oil injection control system;
fig. 3 is a schematic block diagram of a stainless steel rolling oil injection control system in an embodiment of the present invention.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
As shown in fig. 1, a preferred embodiment of the present invention. The stainless steel rolling oil injection control system in the embodiment comprises an oil tank 1, a plurality of oil pumps 2, a plurality of motors, a main pipeline 3, a bypass pipeline 4 and a control module.
The oil tank 1 is used for storing rolling oil; the input end of each oil pump 2 is communicated with the oil tank 1, and the output end of each oil pump 2 is communicated with the other end of the main pipeline 1; one end of the main pipeline 1 is connected with an injection head 5; each motor is respectively connected with one of the oil pumps 2, one end of a bypass pipeline 4 is communicated with the main pipeline 3, and the other end of the bypass pipeline is communicated with the oil tank 1; in addition, in order to realize injection control, a first valve 31 for controlling whether the main pipeline 3 is conducted or not is arranged on the main pipeline 3, a second valve 41 for controlling whether the side pipeline 4 is conducted or not is arranged on the side pipeline 4, and the control module is respectively connected with the first valve 31, the second valve 41 and the motors connected with the oil pumps 2. At least one of the oil pumps 2 is a backup oil pump so as to replace the failed oil pump to complete the injection work.
In the prior art, the motor is a three-phase asynchronous motor, in order to achieve energy saving, and in this embodiment, due to cost limitation, the three-phase asynchronous motor in the prior art is at least partially replaced by a variable frequency motor, each variable frequency motor is further connected with a variable frequency power cabinet, and the variable frequency power cabinet is common knowledge in the industry and is not described herein again; of course, in the case of not considering the cost, the optimal case is that all motors are variable frequency motors.
The control system also comprises a pressure sensor 6 and a PLC control cabinet, wherein the PLC control cabinet has the protection functions of overload, short circuit, open-phase protection and the like, is common knowledge in the industry, and the specific structure of the PLC control cabinet is not described again; the pressure sensor 6 is arranged on the main pipeline 3 and close to the spray head 5 for detecting the spray pressure, and the pressure sensor 6 is connected with the control module. In this embodiment, control module is the PLC controller of locating in the PLC switch board, and the PLC controller is connected with the frequency conversion power cabinet that every inverter motor is connected.
In order to realize energy-saving production during rolling oil injection, the energy-saving method using the stainless steel rolling oil injection control system in the embodiment includes the following steps:
step 1, selecting an oil pump working combination in a control module according to the requirement of jet flow, wherein the set oil pump working combination at least comprises an oil pump connected with a variable frequency motor;
step 3, converting the flow set in the jet flow demand into oil pump outlet pressure in a control module, and comparing the actual pressure measured by the received pressure sensor with the converted oil pump outlet pressure, thereby outputting a control signal to adjust the rotating speed of the variable frequency motor in the selected oil pump working combination;
and 4, controlling a variable frequency motor in the motors to run at the lowest frequency through the control module.
In addition, the rotating speed of the variable frequency motor is adjusted by an actual pressure measured value during the injection, so that the aim of saving energy is fulfilled while the injection set flow is ensured.
In order to explain the control system and the energy-saving method, the number of the oil pumps in the stainless steel rolling oil injection control system in the embodiment is 3, and the oil pumps are respectively a 1# oil pump, a 2# oil pump and a 3# oil pump, and the control system in the prior art is shown in fig. 2, wherein the 1# oil pump, the 2# oil pump and the 3# oil pump are all controlled by asynchronous motors; in order to improve the existing control system, as shown in fig. 3, wherein the 2# oil pump and the 3# oil pump are set to be controlled by inverter motors according to the cost requirement, the inverter motors connected with the 2# oil pump and the 3# oil pump are respectively connected with an inverter control cabinet 1 and an inverter control cabinet 2, and in addition, because the existing control system is connected with a PLC controller, in order to facilitate the transformation of the original control system, thereby a PLC control cabinet is added in the embodiment, the PLC control cabinet is respectively connected with the inverter control cabinet 1, the inverter control cabinet 2 and a pressure sensor, and is connected with the original PLC controller through the PLC control cabinet, and data is interacted.
The energy-saving operation is divided into two modes: a bypass operation mode (short cycle) and an injection operation mode (long cycle), wherein when the PLC control cabinet receives an opening feedback signal of the second valve, the PLC control cabinet is judged to be the bypass operation mode; the oil pumps run at the lowest frequency F1(25HZ, range: 15.0-40.0 HZ adjustable) in the bypass mode; when the PLC control cabinet receives an opening feedback signal of a first valve, judging a jet operation mode (long circulation), converting set jet flow into pump outlet pressure (needing to be determined in a debugging process) according to a flow pressure parameter comparison table stored in advance in the mode, feeding an actual pressure value back to the PLC control cabinet by a pressure sensor, comparing the actual pressure measured by the pressure sensor with converted oil pump outlet pressure by the PLC control cabinet, realizing closed-loop control by a PID (proportion integration differentiation) regulation algorithm, and outputting a control signal to regulate the rotating speed of a variable frequency motor in a selected oil pump working combination, thereby realizing the purpose of energy conservation while ensuring the set flow, and the energy-saving principle of the energy-saving method is as follows: the basic law of fluid mechanics shows that a pump device belongs to a square torque load, and the rotating speed N of the pump device has the following relations with the flow Q, the pressure H and the shaft power P: q ℃. varies.. N, H ℃. varies.. N2, P ℃. varies.. N3; the flow is in direct proportion to the rotating speed, the pressure is in direct proportion to the square of the rotating speed, and the shaft power is in direct proportion to the cube of the rotating speed; when the new PLC control cabinet does not receive opening feedback signals of the second valve and the first valve, the variable frequency motor operates according to the lowest frequency F1.
The rolling oil injection system after the technical transformation finds out after practical verification that: the power frequency operation test of the original two oil pumps is carried out, the average power consumption of each pump during operation is about 106KW, the average input power of each pump after the energy-saving transformation of the system is about 58.3KW, the oil pumps operate for 350 days per year, the unit price of electricity charge is 0.6 yuan/Kw h, and the annual electricity charge is about 48.1 ten thousand yuan. Therefore, the energy-saving method has good energy-saving effect and is suitable for large-scale popularization and use.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (5)
1. A stainless steel rolling oil spray control system comprising:
the oil tank is used for storing rolling oil;
the device comprises a main pipeline, a liquid level control device and a liquid level control device, wherein one end of the main pipeline is connected with an injection head;
the input end of each oil pump is communicated with the oil tank, and the output end of each oil pump is communicated with the other end of the main pipeline;
each motor is respectively connected with one of the oil pumps and is used for driving the oil pump to pump the rolling oil in the oil tank into the main pipeline for injection;
the method is characterized in that: at least one of the above-mentioned motors is inverter motor, stainless steel rolling oil sprays control system still includes:
the first valve is arranged on the main pipeline and used for controlling whether the main pipeline is conducted or not;
one end of the bypass pipeline is communicated with the main pipeline, the other end of the bypass pipeline is communicated with the oil tank, and a second valve used for controlling whether the bypass pipeline is communicated or not is arranged on the bypass pipeline; and
and the control module is respectively connected with the first valve, the second valve and the motor connected with each oil pump.
2. The stainless steel rolling oil spray control system of claim 1, wherein: the device also comprises a pressure sensor which is arranged on the main pipeline and close to the injection head for detecting injection pressure, and the pressure sensor is connected with the control module.
3. The stainless steel rolling oil spray control system of claim 2, wherein: each variable frequency motor is also connected with a variable frequency power cabinet.
4. The stainless steel rolling oil spray control system of claim 3, wherein: the control module is a PLC controller arranged in the PLC control cabinet, and the PLC controller is connected with the variable-frequency power cabinet connected with each variable-frequency motor.
5. An energy-saving method using the stainless steel rolling oil injection control system according to claim 4, characterized in that: the method comprises the following steps:
step 1, selecting an oil pump working combination in a control module according to the requirement of jet flow, wherein the set oil pump working combination at least comprises an oil pump connected with a variable frequency motor;
step 2, when rolling oil is required to be sprayed, the first valve is controlled to be opened through the control module, meanwhile, the second valve is controlled to be closed, and the step 3 is carried out; when the rolling oil is not required to be sprayed, the first valve is controlled to be closed through the control module, meanwhile, the second valve is controlled to be opened, and the step 4 is carried out;
step 3, converting the flow set in the jet flow demand into oil pump outlet pressure in a control module, and comparing the actual pressure measured by the received pressure sensor with the converted oil pump outlet pressure, thereby outputting a control signal to adjust the rotating speed of the variable frequency motor in the selected oil pump working combination;
and 4, controlling a variable frequency motor in the motors to run at the lowest frequency through the control module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111526496.2A CN114178320A (en) | 2021-12-14 | 2021-12-14 | Stainless steel rolling oil injection control system and energy-saving method using same |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111526496.2A CN114178320A (en) | 2021-12-14 | 2021-12-14 | Stainless steel rolling oil injection control system and energy-saving method using same |
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| Publication Number | Publication Date |
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| CN114178320A true CN114178320A (en) | 2022-03-15 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200939457Y (en) * | 2006-08-18 | 2007-08-29 | 上海诸光机械有限公司 | Controller of lab system of hot rolling steel plates tandem mill |
| CN102814339A (en) * | 2012-08-30 | 2012-12-12 | 镇江市宏业科技有限公司 | Rolling oil controlling system |
| CN104384205A (en) * | 2014-12-04 | 2015-03-04 | 镇江市宏业科技有限公司 | Process oil pressure control system of rolling mill |
| CN109092914A (en) * | 2018-08-06 | 2018-12-28 | 鞍钢未来钢铁研究院有限公司 | A kind of steel rail rolling lubricating method and device |
-
2021
- 2021-12-14 CN CN202111526496.2A patent/CN114178320A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200939457Y (en) * | 2006-08-18 | 2007-08-29 | 上海诸光机械有限公司 | Controller of lab system of hot rolling steel plates tandem mill |
| CN102814339A (en) * | 2012-08-30 | 2012-12-12 | 镇江市宏业科技有限公司 | Rolling oil controlling system |
| CN104384205A (en) * | 2014-12-04 | 2015-03-04 | 镇江市宏业科技有限公司 | Process oil pressure control system of rolling mill |
| CN109092914A (en) * | 2018-08-06 | 2018-12-28 | 鞍钢未来钢铁研究院有限公司 | A kind of steel rail rolling lubricating method and device |
Non-Patent Citations (1)
| Title |
|---|
| 孟旭兵;李昕;董玉杰;: "不锈钢冷轧机轧制油过滤系统分析", 一重技术, no. 04, pages 34 - 37 * |
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