Metallurgical Industry

Introduction:
The metallurgical industry relies on advanced automation systems to optimize production processes, ensure safety, and enhance efficiency. This case study highlights the successful collaboration between UniMAT, a fictional service company specializing in industrial automation, and MetaTech, a leading metallurgical company. UniMAT implemented their expertise using the ST30 CPU, a reliable programmable logic controller (PLC), in a project that has been operating smoothly without any reported issues.

Client Overview:
MetaTech is a renowned metallurgical company specializing in the production of high-quality metal products. With a focus on operational excellence, MetaTech aimed to optimize their manufacturing processes through the integration of advanced automation systems.

UniMAT's Solution:
UniMAT, a trusted provider of industrial automation solutions, proposed a tailored automation solution to meet MetaTech's specific requirements. The ST30 CPU, known for its reliability and performance, was selected to provide seamless control and monitoring capabilities in MetaTech's metallurgical processes.

Implementation and Integration:
UniMAT's automation experts closely collaborated with MetaTech's team to understand their production workflows and identify areas where automation could bring significant improvements. Based on the analysis, the ST30 CPU was chosen for its robust features, efficient programming options, and compatibility with MetaTech's existing infrastructure.

Installation and Commissioning:
Following the solution selection, UniMAT's skilled technicians proceeded with the installation and commissioning phase. They seamlessly integrated the ST30 CPU into MetaTech's metallurgical processes, ensuring proper wiring, configuration, and programming. Rigorous testing and quality checks were performed to ensure the system's functionality and compatibility.

Operational Performance:
Upon completion of the installation, MetaTech experienced a noticeable enhancement in their production efficiency and product quality. The UniMAT solution, powered by the ST30 CPU, provided precise control and real-time monitoring, enabling MetaTech to optimize their metallurgical processes. The automation system streamlined operations, reduced errors, and increased overall productivity.

Stable Operation and Reliability:
Since the implementation, the UniMAT solution integrated with the ST30 CPU has been operating smoothly without any reported issues or disruptions. MetaTech commends UniMAT for the system's stability and reliability, which have contributed to uninterrupted production and consistent product quality.

Conclusion:
The successful collaboration between MetaTech and UniMAT exemplifies the positive impact of automation in the metallurgical industry. By integrating UniMAT's solution, utilizing the reliable ST30 CPU, MetaTech achieved improved production efficiency, enhanced product quality, and optimized operational processes. UniMAT's commitment to delivering reliable and robust automation solutions ensures that companies in the metallurgical sector can achieve operational excellence and maintain a competitive edge. This case study showcases UniMAT's expertise in providing seamless automation integration and highlights the benefits of utilizing advanced technology to drive productivity and quality in the metallurgical industry.

Introduction:
The metallurgical industry plays a pivotal role in the manufacturing and construction sectors, requiring efficient and precise processes for metal extraction, refining, and fabrication. UniMAT, a trusted leader in the automation industry with 18 years of expertise, specializes in providing cutting-edge automation solutions. This case study highlights how UniMAT's innovative automation technologies transformed a metallurgical plant in the bustling city of Shanghai, China, enhancing productivity, quality control, and operational efficiency.

Case Study: MetaSteel Metallurgical Plant in Shanghai, China

Overview:
The MetaSteel Metallurgical Plant, an industry-leading facility situated in Shanghai, China, faced challenges related to process optimization, quality assurance, and safety in their metal production operations. Seeking to improve their manufacturing processes, reduce downtime, and enhance overall performance, they partnered with UniMAT, a renowned automation solutions provider.

Challenges Faced:

Process inefficiencies: The existing manual operations resulted in inconsistencies, leading to variable metal quality and reduced production efficiency.
Quality control: Ensuring consistent metallurgical properties and meeting stringent quality standards posed a significant challenge, resulting in rework and wastage.
Safety concerns: Manual handling of hazardous materials and insufficient safety measures increased the risk of accidents and occupational hazards.
Downtime and maintenance: Unscheduled downtime due to equipment failures and the lack of predictive maintenance adversely affected production schedules and profitability.
Solution Implemented:
UniMAT collaborated closely with MetaSteel to develop a customized automation solution that addressed their specific challenges and goals. Leveraging UniMAT's 18 years of industry experience and expertise in self-driven research and innovation, the following solutions were implemented:

Key Components of the Solution:

PLC-based control system: UniMAT integrated a state-of-the-art PLC-based control system to automate critical metallurgical processes, ensuring precise control and optimization.
Robotic automation: Collaborative robots (cobots) were introduced to handle hazardous tasks, improving worker safety and operational efficiency.
Real-time monitoring and data analytics: UniMAT's advanced data acquisition and analysis tools provided real-time insights into process variables, enabling proactive decision-making and process optimization.
Quality assurance measures: UniMAT implemented integrated quality control systems, incorporating automated inspections and testing mechanisms to ensure consistent metallurgical properties and adherence to quality standards.
Predictive maintenance: UniMAT's solution included predictive maintenance capabilities, leveraging machine learning algorithms and data-driven insights to identify potential equipment failures and schedule maintenance activities.
Benefits Achieved:

Improved productivity and efficiency: The automation solutions resulted in optimized process control, reduced cycle times, and increased overall productivity.
Enhanced quality control: UniMAT's automation technologies enabled consistent metallurgical properties, reduced defects, and improved product quality, leading to higher customer satisfaction.
Enhanced worker safety: Robotic automation and improved safety measures minimized the exposure of workers to hazardous materials, reducing accidents and ensuring a safer work environment.
Predictive maintenance and reduced downtime: By implementing predictive maintenance strategies, equipment failures were minimized, leading to reduced downtime and improved operational continuity.
Cost savings and profitability: UniMAT's automation solutions contributed to reduced operational costs, increased resource utilization, and improved overall profitability for MetaSteel.
Conclusion:
UniMAT's successful collaboration with MetaSteel showcases the transformative power of automation in the metallurgical industry. With UniMAT's 18 years of deep industry experience, research, and innovation, the implementation of customized automation solutions led to significant improvements in productivity, quality control, safety, and profitability for MetaSteel in Shanghai, China. This case study exemplifies UniMAT's commitment to delivering innovative automation solutions that drive operational excellence and contribute to the success of their clients in the metallurgical industry.

I. the basis of system design

According to the general drawings of a new 10M2 shaft furnace project of a company, the system is designed on the basis of the successful experience of the similar system and the technological requirements, system structure and main functions of shaft furnace production. Yes.

The system includes four parts: high voltage, low voltage, instrument and automation. Here, we mainly introduce the automatic control system of shaft furnace.

 

2.System overview

 

A. main function description and equipment

 

A large number of instruments and sensors are used to collect temperature, pressure, flow and other data. Our company integrates a variety of signals into the computer automatic control system to achieve real-time monitoring and control of process parameters in the production process.

 

Shaft furnace automation system adopts the whole network, full digital structure, using Siemens S7-300 PLC and Uygur UniMAT I/O module, Yanhua ADAM module and the upper computer to form an electronic control, instrument control, computer control "three electricity" system structure.

 

The main equipments of shaft furnace production technology are: batching, drying, pelleting, raw sieve, cloth, baking, unloading, finished product winch, etc. Auxiliary equipment: blower, circulating water pump, soft water pump, gas pressurization, drum cooling, electrostatic precipitation, thin oil lubrication, electrical automation system and instrumentation system.

 

B. Process Overview

Shaft furnace pellet production is a complex process which integrates gas making, grinding, batching, drying, pelletizing, distribution, sintering and discharging. First of all, the powder iron concentrate and bentonite from the raw material factory, according to a certain proportion, form a mixture after the batching system, from the belt machine to the dryer, after the dryer dehumidification and mixing evenly into the disc pelletizer, so that raw materials form a certain size of ball (green ball). Then the raw balls pass through the distributor and enter the shaft furnace. The raw balls are sintered according to certain rules. The finished balls are exported to the finished pellet yard as the burden for iron-making.

 

The main control link in production is the shaft furnace section, and its technological process is shown in Figure 1. The raw balls from the pelletizing section are sent to the drying bed through a distributor; after being dried, the raw balls are fed into the shaft furnace, which undergo preheating, sintering and even tropics. The heat exchanged in the three temperature zones comes from the two combustion chambers of the shaft furnace itself; after being cooled, the high-temperature cooked balls are discharged to the shaft furnace through the rotation of the tooth rolls. Finally, the vibrating feeder sends the cooked balls to the discharging car to transport to the stock yard.

Three, system requirements

From a functional point of view, the shaft furnace system consists of four links. The technological process and influencing factors in each link are as follows:

3.1 temperature control links:

 

Temperature distribution in shaft furnace is one of the determinants of pellet quality. It is generally believed that there are five zones in shaft furnace roasting pellet, which are dry zone, pretropical zone, roasting zone, even tropical zone and cooling zone. The ideal temperature distribution curve is roughly shown in Fig. 2.

In fact, the temperature distribution of shaft furnace is often difficult to form an obvious temperature zone, so it is not desirable to control its temperature directly and accurately. The temperature in the shaft furnace is usually indirectly controlled by controlling the temperature of the combustion chamber. The main factors affecting the temperature of combustion chamber are the flow rate of gas and combustion-supporting air, so in the temperature control link, the flow rate of gas and combustion-supporting air is mainly controlled.

 

3.2 air control links:

It is very important, not only the combustion-supporting air in the temperature control link, but also the research and application show that changing the composition and distribution of air flow (mainly cooling air) can change the temperature distribution in the furnace to a certain extent.

 

3.3 cloth control links:

Uniform distribution is very important for optimizing roasting and furnace conditions. The main factors leading to uneven cloth distribution are uneven raw balls, uneven working mechanism and so on. In this system, it is assumed that the raw ball feeding is uniform. In view of the working mechanism of the cloth truck, our company introduces PLC logic control to achieve the action requirements of the cloth truck.

 

3.4 unloading control:

 

 

Four, system configuration and function realization

 

 

 

Based on the above analysis of the design concept and process of shaft furnace system, the control scheme is as follows:

 

 

 

4.1. Automation system composition

 

 

 

The automatic control system is set up according to its functions as follows: raw material system, drying system, pelleting system, raw sieve material distribution system and shaft furnace body system. The electrical and instrumentation parameters in the system are monitored and controlled separately. The belt scale control system composed of single chip microcomputer and the raw sieve material distribution system are controlled by PLC respectively. The main system of shaft furnace is controlled by Yanhua data module. The above systems are equipped with network communication module to ensure the normal communication between the upper computer and PLC and facilitate on-line monitoring and online modification. The upper computer monitors and issues instructions to complete the control of the whole process of shaft furnace production.

 

 

 

4.2 control function

 

 

 

The system mainly performs the following four functions:

 

 

 

4.2.1 data acquisition

 

 

 

ADAM data acquisition module is responsible for collecting gas, combustion-supporting air, cooling air flow, pressure and temperature of each part of the shaft furnace. After processing, the corresponding effective process parameters are transmitted to the industrial control computer of the shaft furnace section through the communication module, and the upper computer automatically adjusts according to the set algorithm.

 

 

 

Example: The pressure measurement conversion unit adopts capacitive pressure transmitter with accuracy of 0.2. The transmitter generates a 4-20 mA signal corresponding to the actual pressure, which is then received by Yanhua analog acquisition module. The real-time pressure value is displayed on the configuration screen.

 

 

 

4.2.2 valve control

 

 

 

Valve control is mainly to control the opening and measuring of each electric control valve. The input control signal of the valve controller is 4-20 mA current signal, and the electric control valve generates 4-20 mA valve position feedback signal output. The valve control system is composed of servo regulator and ADAM module. The control signal is sent to the control module through the industrial computer. The control module outputs the control signal to the operator. The operator outputs the control signal to drive the actuator to make the electric regulating valve reach the specified opening. The valve position opening signal is feedback and transmitted to the industrial computer through the data acquisition module. .

 

 

 

4.2.3 production process control

 

 

 

The main control objects are the distributor and unloader, the disc feeder in the pelletizing section, the disc pelletizing machine in the pelletizing section, the belt and so on. Considering the coordination and interlock between the equipments in the production process and the safety, stability and reliability requirements of the control system, Siemens 300 CPU and 100 million-dimensional distributed I/O series modules are adopted to control the system.

 

 

 

4.2.4 user interface

 

 

 

User interface functions mainly include: processing process parameters from data acquisition system, forming user interface in production; adopting corresponding control strategies and algorithms according to process parameters, forming a reasonable control output to the valve control system or production process control system; displaying the process flow chart of each production process; important process; Real-time display of parameters, historical trend chart display, fault alarm and event record display, gas consumption report display, etc.

 

 

 

 

 

4.3, the composition of control system

Control of 4.3.1 shaft furnace system

 

 

 

Shaft furnace system control mainly includes: raw material control system, pelletizing chamber system, drying control system, raw sieve cloth, baking system, finished product system; auxiliary system: circulating water pump room, soft water station system, blower station system, electrostatic precipitation system, gas pressurization system and other major systems. elaborate

 

 

 

4.3.2 raw material control system

 

 

 

The raw material system is mainly composed of disc feeder and belt weigher. The equipment adopts frequency conversion to control the disc and can adjust the material flow at any time according to the need. Control mode: centralized control and manual beside the machine, the machine can be adjusted according to the needs of manual speed, and with the speed display on the box to achieve speed requirements, centralized in the upper computer through the configuration screen speed setting, input the corresponding parameters in the screen, the system can be root The matching speed between the disc feeder and the belt scale is adjusted automatically according to the set parameters, and the matched raw materials are sent from the 1# belt to the dryer. This system is mainly accomplished by the logic process of automatic control by single chip microcomputer.

 

 

 

4.3.3 drier control system

 

 

 

The raw material delivered by the 1# belt conveyor is fed to the dryer through vibrating feed hopper. The dryer system consists of a dryer, a combustion-supporting fan, a feeding belt, a wall vibrator and an instrument. It is used to mix the powder iron concentrate and bentonite in a certain proportion in the raw material factory, and remove the excess water by the dryer to make the raw material mix evenly. The drier is controlled by soft start to reduce the impact of current.

 

 

 

The interlocking conditions controlled by the drier are: 2# belt running, dryer, 1# belt.

 

 

 

 

Instrument monitoring points are as follows

 

 

 

Temperature measurement: there are two points: the outlet temperature of the combustion furnace is 1, the temperature of the drying hood is 1.

 

 

 

Pressure measurement: there are two points, which are combustion supporting manifold pressure and gas main pressure.

 

 

 

Flow measurement: a total of 1 points, gas main flow.

 

 

 

The instrument cabinet is equipped with a manual/automatic regulator to regulate the pressure of the main gas pipe and the outlet temperature of the combustion furnace.

 

 

 

4.3.4 ball making system

 

 

 

The disc pelletizer makes a raw ball with a certain size (raw balls). In the system, the disc feeder is controlled by frequency conversion, and the pelletizer is controlled by soft start. Because the water in the raw material is difficult to control and the size of the ball is uniform in the production, the operator needs to observe the disc feeder in real time and take corresponding measures. Therefore, the automatic PID control method is not suitable for each disc, and it is mostly manual. The pelletizing machine is equipped with an operation box beside the machine. The speed of the disc feeder, the electric vibration and the start and stop of the pelletizing machine are controlled by adjusting the potentiometer. The produced pellets are transported from the 4# belt to the screening machine.

 

 

 

4.3.5 screening roasting system:

 

 

 

The raw balls from the pelletizing machine are screened and distributed into the shaft furnace. The raw balls are fired. The interlocking between the equipments is as follows:

 

    

4.3.6 body baking system:

 

 

The main objects to be controlled include: gas main pipe, branch electric regulating valve, combustion-supporting air main pipe, branch electric regulating valve, cooling air main pipe flow electric regulating valve, distributor and unloader. In order to give full play to the performance of the equipment and ensure the safety and reliability of the whole production process, the automatic control system adopts two-stage computer control scheme, the upper computer adopts industrial control computer, the lower computer adopts Siemens PLC and the I/O module of UNIMAT.

 

 

 

For the automatic distribution system, mainly open-loop control, control the speed of the distribution truck to and fro to achieve uniform distribution. The control method of PID and neural network is adopted in the temperature control of shaft furnace.

 

 

 

Temperature control of shaft furnace is mainly to control the temperature of combustion chamber within the range of technological requirements. Two closed-loop PID control loops can be used to form a gas and combustion-supporting air proportional control system to control the temperature of combustion chamber. Its system control block diagram is shown in Figure 3

The PID controller is designed as a single neuron adaptive PID controller, which can dynamically adjust the three parameters of the PID controller to meet the requirements of real-time control.

 

 

 

 

 

4.4 control system monitoring screen is as follows

 

 

 

The 4.4.1 roasting system is shown below.

The temperature, pressure, flow rate and valve opening can be monitored and adjusted by this screen. The picture also includes the drum level, the start and stop of the soft water pump, and the running state.

 

 

 

4.4.2 The amount of gas used in the production should be recorded in the report form, so as to facilitate the regular statistics of the use of gas and bring convenience to the production scheduling. The gas cumulative flow chart is as follows:

4.4.4 alarm screen: including all the points in the main screen, by setting the upper limit, lower limit or state can effectively alarm the collected parameters, remind the operator to find the problem early so as to deal with the problem in time. Can also be in the event of failure through alarm records to analyze the problem, to prevent similar problems in the future recurrence.

4.4.5 gas flow curve: we can observe the flow at different time points and monitor in real time.

4.5 the high-pressure system is not explained here.

 

 

 

 

 

5., use effect analysis

 

Under the condition of meeting the technical requirement and according to the working requirement of each equipment, this automatic control system chooses the PLC-300 series CPU of SIEMENS Company and the I/O module of Uygur dimension, which improves the stability of the system and saves the cost of the system to a certain extent. The system is in good condition after being put into operation.

Abstract：Combining with the actual situation of 680M3 blast furnace electric automation instrument control system of Qinhuangdao Baigong Iron and Steel Co., Ltd, the paper emphatically expounds the reasonable application of UniMAT UN200 and UN300 series PLC expansion modules in charging system, hot blast stove system, bag dust removal system, blast furnace charging and distribution system, body instrument detection system and blower room. System, pump station system and screen monitoring, software function and other successful cases. This paper mainly introduces the design scheme of four sets of PLC system, such as feeding PLC main station, main body PLC main station, hot air PLC main station and bag PLC main station.

 

I. overall system design concept

 

According to the blast furnace technology, the general idea of low cost and high performance is adopted in a reasonable way. The automation system adopts the open structure of three-power integration, which creates conditions for the future expansion of the system, and retains the interface ability of the regional computer and the whole factory management computer.

According to the characteristics of blast furnace system decentralization, the master-slave network structure is adopted: the substation is connected to the master station system through the network line, which reduces the cable consumption, facilitates maintenance and greatly reduces the cost. Such as UniMAT IM153-1 can be used as a single slave station, and can be installed near the distribution room of blast furnace equipment. The cloth bag blowback is designed by matrix. The structure is simple, and the number of module points used is reduced.

The system uses billion-dimensional PLC as the basic control station to complete the control and monitoring of on-site process equipment; the upper operation uses billion-dimensional industrial control computer as the operating station to carry out man-machine dialogue, real-time monitoring of on-site equipment operation and various instrument parameters. In order to ensure the normal operation of the production under various circumstances, the system is mainly automatic, and the upper computer is reserved for each other.

 

In principle, the selection of automation device adopts the new technology and equipment at present detection level, and considers that the structure of control system is simple, practical and reliable, which fully meets the technological requirements. Reduce investment by ensuring product quality and ensuring that the system meets process requirements and performance as a whole.

2.system configuration

 

This system can provide service for blast furnace operation and make the controlled equipments operate conveniently and centrally on the computer of the main control building, and record the operation of these equipments truthfully.

 

1)automatic monitoring system:

 

A1 network structure adopted

 

The upper computer adopts industrial Ethernet, which fully meets the requirement of large amount of data transmission between upper computers; the PROFIBUS-DP fieldbus is used between PLC and remote station to meet the real-time and reliability of field data transmission; the network block diagram is as follows:

There are mainly six industrial control computers as operating stations, which are hot air, bag, skilled operator, main instrument, ore trough feeding, furnace top equipment, and can be reserved for each other.

 

PLC has four sets of Siemens 400 series main PLC system, feeding PLC main station, main body PLC main station, hot air PLC main station, cloth bag PLC main station, under the respective expansion module to complete the system control and data acquisition. Data exchange between PROFIBUS-DP network and operation station is completed.

 

B. hardware and software components

 

PLC selects the high performance and low cost module structure of UniMAT 200+300.

 

Computer operation console: stainless steel surface console

 

Programming software selects STEP7 V5.4, and configuration software selects my WINCC 6 SP3.

　　

3. Hot stove control system

 

The blast furnace is equipped with three hot blast stoves, which are mainly responsible for combustion, heat storage, cold air heating, and hot air into the blast furnace. Because a hot blast stove is intermittent heat exchange, and the blast furnace needs continuous hot air, so the three hot blast stoves work periodically, including combustion, blast stove, blast three processes.

 

Hot blast stove sequence control system has the following operating modes: automatic, semi-automatic, CRT manual mode, side box operation

 

Introduction to the working state of hot blast stove

 

A hot blast stove can be converted from "blowing" to "smoldering" to "burning" or from "burning" to "smoldering" to "blowing".

 

"Air supply" means that the hot stove is pressurized and both the cold air valve and the hot air valve are opened. All other valves are closed (excluding mixed air shutoff valves and heat exchanger valves).

 

"Combustion" means that the hot stove is decompressed, the cold air valve, the hot air valve and the cold air charging valve are closed, the exhaust gas pressure equalizing valve is opened, and the combustion-supporting air and gas are introduced into the hot stove.

 

"Suffocation" means that all the valves of the hot stove are closed, but the pressure control is still in operation, and a hot stove is ready to be charged or equalized at any time.

 

Working system of hot blast stove:

 

Under normal conditions, the hot blast stove adopts the parallel air supply, or the two-burning-one-feeding system, and the abnormal operation is one-burning-one-feeding system.

 

Each hot-blast stove can automatically switch between the three states of "stove", "air supply" and "combustion". Each valve switch is controlled by PLC program. After issuing the order of changing stove, the hot-blast stove equipment carries out interlocking action according to the sequence of technological requirements.

 

 

4. Dry type purification control system for blast furnace gas

 

The blast furnace gas dedusting facility is the auxiliary facility of the blast furnace. Its purpose is to purify the blast furnace gas and improve the quality of the gas. After the blast furnace gas is dusted by gravity dust collector, it enters the lower part of the main box of cloth bag. When the gas passes through the cloth bag, the dust carried by the gas is intercepted by the cloth bag, and the filtered and purified gas is transported to the hot blast stove or the gas pipe network through the high pressure valve group for users to use. Dust filtered by bag filter is washed by pulse valve and falls into ash storage bin; unloading valve is opened, output by scraper, and sent to high ash bin by bucket lift.

1)This set of facilities has designed three kinds of back-blowing methods, time back-blowing (set time to), pressure back-blowing (pressure difference is higher than the set value), manual back-blowing.

2) The dust removal system consists of two control processes: back-blowing and dust discharge, all of which can be controlled manually, semi-automatically and automatically.

The automatic blow back mode is: differential pressure reverse blow and timing blow. Differential back-blowing is when the box differential pressure is higher than the set differential pressure value (3KPA), automatic back-blowing starts when the timing time reaches the set back-blowing time.

A. When barren clean gas main pipe pressure difference reaches 6 ~ 8Kpa (can be set) to carry out anti blow. At the same time, the timing blow option is selected, and the cloth bag is blowback through the same period.

B.The backblowing time of the chamber is 10-20 seconds (adjustable). The backblowing sequence is N1, N2, N3... N10. The nozzles on the air drum are also sequentially operated n1, n2, n3.... N14 until all the 10 chambers are blown back, and the backblowing process is over.

C. box reverse blow by off-line blowback. When the total pressure difference of clean waste gas reaches a set value of 6Kpa, the inlet and outlet butterfly valves of the working box body are closed first, and then the back blowing is carried out. Immediately after the blowback, the butterfly valve of the inlet and outlet is opened, and the reverse blow of the next box is carried out in turn.

D. each bag has a jitter of 2 times per time (adjustable).

E. automatic operation of discharging ash is: timing ash unloading. Set the discharging time, automatically start the discharging bucket lifter, hanging plate machine, according to the technical requirements to open the selected discharging box on the equipment (up discharging valve, down discharging valve, impeller feeder, ash bucket plug removal device pulse valve), generally set 3/24, automatically complete the discharging operation.

The action sequence of the lower part of the intermediate warehouse:

When the upper part of the N1 cabinet is discharged, the middle bin is discharged. The common equipment, i.e. inclined tube vibrator bucket lifter scraper conveyor, is first opened. Open after completion: N1 box electric feeder N1 box lower electric ball valve N1 box middle bin wall vibrator. After a delay of 30 seconds, close the lower part of the intermediate store.

The order is: the storehouse wall vibrator in Guanzhong warehouse, the lower part of the N1 box, the electric ball valve, the electric feeder.

After the bottom of the N1 box is unloaded, the bottom of the N2 box will be unloaded with N1 box. Followed by N3 boxes, N4 boxes, N5 boxes... N8 box.

When the bottom of the N10 box is discharged, the public equipment is closed. The order is:

Scraper conveyor, bucket elevator and inclined tube vibrator.

 

2)The operation sequence of the lower part of the high ash bin is all machine side operation, and the other equipment is controlled by PLC. :

Opening: humidifier ash discharging machine, electric ball valve, silo wall vibrator.

Closing: wall wall vibrator to electric ball valve to humidifier and ash disposal machine.

 

5. Charging system for blast furnace

The charging part of the blast furnace consists of two parts: the ore trough weighing and the top of the furnace. The two parts are connected by the charging truck. The charging function is completed by the coordinated action of the ore trough, the charging truck and the furnace top equipment according to the technological setting.

All kinds of materials are screened by vibrating screen and then directly loaded into the weighing bucket. Then a weighing bucket is loaded into the truck. The powder under the screen is transported to the silo by crushing belt, waiting for the truck to go out. The skip is driven by the main hoist to convey the ore to the top loading equipment and reach the parking space after 2 stages of speed change. The quality of each bin is changed at any time according to the requirements of the formula, and the operation of weighing and loading is automatically completed.

1)Equipment composition

The 680 M3 blast furnace is equipped with double-row storage tanks, which store sinter, pellet, coke and miscellaneous ores respectively. Four coke tanks, six sintering tanks, four pellets and four miscellaneous ores are arranged in pairs under the tanks. The top of the furnace consists of hopper, stopper valve, upper sealing valve, lower sealing valve, material flow valve, rotating mechanism, tilting mechanism, material tank, pressure equalizing valve, pressure equalizing and releasing equipment.

2)feed cycle control system, the most commonly used for the following two systems.

Two car value: OC or CO

Four car value: OO CC or CC OO

Description: O stands for sinter, pellet and miscellaneous ore; C represents coke.

Several different charging systems are combined to form batch cycle, continuous cycle feeding, to meet the continuous production requirements of blast furnace.

3). Control Requirements: According to the technological requirements, display and control the relevant technological parameters of the trough, charging and furnace top equipment system, and record the trend of the relevant parameters. It includes 14 electronic weighing records, material level measurement, control and display of TRT and various signals of blast furnace and TRT.

Temperature detection of water cooling system: when the temperature difference between inlet and outlet of chute gear box is greater than 5, alarm signal is issued, prompting the relevant personnel to check water flow and blast furnace top temperature; when the temperature difference is greater than 50, immediately check the water cooling system.

When the difference between the tank pressure and atmospheric pressure is less than 20KPa, the interlock signal is sent out, and the upper sealing valve is opened by an electric power professional; when the difference between the tank pressure and the furnace top pressure is less than 20KPa, the interlock signal is sent out and the lower sealing valve is opened.

 

6.The air tight box is cooled with nitrogen flow control valve to control the opening.

 

Blast furnace body instrumentation control system

The top-down blast furnace consists of five parts of the throat, furnace body, furnace belly, hearth, furnace foundation and related water system. All meter points are connected to the data collector and transmitted to the upper computer through communication.

The main tasks of blast furnace process detection and control are: collecting temperature, pressure, flow and other data, adjusting and controlling the pressure reducing valve group, monitoring furnace reactions, and protecting furnace body and equipment.

1) water control at the top of the furnace

When the temperature of the gas riser is too high, it will alarm and open the top.

2) top gas pressure control

The pressure control system of blast furnace top gas regulates the opening of pressure reducing valve group after bag filter to maintain the stability of top gas pressure.

3)leak detection and drainage temperature measurement

 

In order to protect furnace safety, leak detection is a very important test item. Measuring the inlet and outlet flow difference of cooling water in tuyere, measuring the temperature of the tuyere drainage, can check whether the tuyere is intact.

 

Seven, picture introduction

 

The screen system is the man-machine interface between the operator and the control system. The operator operates the equipment and monitors the operation of the equipment through the screen. The screen system can set the data, change the operation mode, and display the normal state of the equipment and alarm information to the operator.

 

The main contents of the CRT display are as follows:

 

(1) System picture: hot air, cloth bag, mine trough, furnace top, body instrument, furnace head operating furnace, furnace top instrument, etc.

(2) control setting screen: setting of ingredients, roof chute angle and material flow opening parameter setting.

(3) failure monitoring screen: real-time display of fault signals, prompting operators to take corresponding measures.

(4) alarm record: record the failure alarm of each equipment and meter.

(5) report record: real-time record of production parameters.

The following main picture is introduced.

 

7. Loading screen:

 

Including the entire poplar and furnace top equipment, which are mainly feeding trolley, left and right probe, plunger valve, top density, bottom density, rotating distribution device, pressure equalizing valve, release valve and so on. Manual and automatic conversion can be realized in production at any time, all kinds of operation and faults have different colors to display, features 1, car inflection point, unloading level and other deceleration point parking space can be adjusted according to production 2, rotating cloth angle and speed can be set directly through the screen, to meet the production process of various cloth mode 3, in the maintenance or Under the training of new employees, simulation production can also be done by setting various data in the picture.

The instrument on the top of the blast furnace is very important for ensuring the normal equipment of the furnace top.

2)mine slot picture

 

It mainly includes belt, hopper, vibrating screen operation, stop, fault indication and operation. The weight of various materials can be set in advance in this screen, and the automatic feeding can be completed by adjusting the periodic table according to the requirements of various batches under the furnace head. It can also transfer individual control to field operation by machine-side switch. There are manual (green) and automatic (purple) instructions in the screen. There are also periodic table subgraphs. As follows:

Adjust the recipe and generate the recipe automatically. As follows:

Production report record screen, real-time production cost control, as follows:

3) Hot blast stove screen

This screen can realize the operation of combustion-supporting fan, pressure regulating valve group, combustion-supporting regulating valve, mixing air valve, cold air valve, hot air valve, release valve, cold air pressure equalizing valve, gas regulating valve, air regulating valve, air shutoff valve, gas shutoff valve and various process valves and display instrument parameters. It can automatically accomplish all stages of hot blast stove conversion to achieve automatic air supply, braising and burning. Various valves in the screen can be point-operated, regulating valves are automatically adjusted by entering predetermined values or clicking on the scroll bar. Figure:

4) bag dust screen

It includes pulse valve, up and down ash discharging valve, release valve, top gun, down gun, ash conveyer, bucket lifter, inlet and outlet butterfly valve and inlet and outlet blind valve, and displays the running state of the equipment and the parameters of various instruments. With the mouse click each valve can automatically pop up the control menu, pulse valve for dynamic display, can be found at any time because of frequent action and damage to the solenoid valve. Pulse time and box selection can be set according to requirements.

Automatically purge under automatic condition, and start from 1 to 8. If there is a problem in a box, it will automatically jump over the box to execute down. The picture is as follows:

5) It is the key for the production and high production of the blast furnace to adjust the furnace condition reasonably through the screen parameters

6)The appearance of the body instrument. The BF instrument is to monitor whether the blast furnace lining is normal, mainly including water temperature and pressure.

8. concluding remarks

 

Each action and state of the automatic control system of blast furnace is controlled by PLC, which not only meets the requirements of a large number of presses, switches and position detection points required by centralized control mode, machine-side control mode and two-way control mode of each equipment, but also chooses a reasonable configuration method according to different technological requirements. The master-slave structure of the network, the matrix structure of the bag blowing back, etc., and the PLC industrial LAN can be composed of interface components and computers to realize network communication and network control. The electric automation instrument control system of the blast furnace can be conveniently embedded into the production line of the iron and steel industry.