CIPDB › China Industry › Metallurgy, Mineral & Energy › Metallurgy Machinery

China, Chinese Innovative Heavy Oil Double-Sided Reheating Furnace for Conventional Slab¹ Industrial Products Supplier Manufacturer Details, price list catalog:

Preview:

Product Description Product Description1 Design Conditions and Basic Technical Parameters 1.1 Furnace Type: A walking beam reheating furnace which is used for reheating the slab with the fuel of heavy oil (phase 1) and coke oven gas (phase 2); Walking beam mechanism:two wheels on slope rail, hydraulic drive; Charging /discharging mode: charging with pusher at charging side, discharging with extractor at discharging side; 1.2 Steel Grades for Heating: low carbon steel, medium carbon steel, including pipeline steel C-60 and X-70; 1.3 Dimensions and Proportion of Billets: -- The Specification of billets: Length: 4.5~11m Width: 900~1270mm Thickness: 200mm, 210mm -- The proportion of billets: A) 4.5 meter length slab charging: Maximum 5.0% B) 6.0 to 8.0 meter length slab charging: Maximum 5.0% C) 11.0 meter length slab charging: 90% We can know from the charging diagram, the billet size of 7-8m is not suitable for charging 1.4 Charging and Discharging Temperature: Charging temperature: cold charging, room temperature, completely hot charging 600 ~ 900oC Discharging temperature : 1250±30oC; 1.5 Fuel: 1 ) phase 1 (within one year after putting into operation) Heavy oil with calorific value of 10200 Kcal/kg; 2 )Phase 2(one year later after putting into operation) ;coke oven gas with calorific value of 4000 kcal/m3; 1.6 Output of Reheating Furnace: Rated output is 250t/h ( cold charging, room temperature,210 mmx1270mm x 11000mm,common carbon steel, discharging temperature 1250oC); max output is 300t/h ( completely hot charging 600 ~ 900 oC ,210 mmx1270mm x 11000mm,common carbon steel, discharging temperature 1250oC);1.7 Control level of 1.7 Control Level of Furnace: (1) Sequence control system: the production process that the conveyance of slab from charging roll table to discharging roll table and transferring the slab before the rolling mill can realize the computer automatic control; (2) Combustion control system: the computer system which can realize the automation control for furnace temperature and furnace pressure; 1.8 Cooling Mode: Evaporation cooling and forced circulation are adopted for skid cooling; 2 Process Overview 2.1 Charging Enter billets information such as the serial number, steel No., weight and length ,width, thickness and temperature of continuous casting billets into the PLC of the sequence control system of the reheating furnace for billets positioning and material tracing ( when the continuous casting billets information can not be transmitted to the reheating furnace effectively, the equipment located on the roller table should be set the functions for weighing, length-measurement, examination and temperature measurement etc.) After billets are positioned based on the arrangement diagram and identifying the vacant position in the furnace, the charging door will open, the pusher will move forward and push billets to the slideway of the transition bench with a distance of 50-150mm to the former billet in the furnace (this distance can be adjusted according to the requirements of billets and production), Then the pusher will return to the initial position and prepare for the next charging ,the charging door will close at the same time ,thus completing a charging process . 2.2 Conveyance of Billets in The Furnace The path of motion of the walking beam is of rectangle shape. The movement of walking beam is made up of horizontal and vertical movement. The speed during the horizontal and vertical movement will be changed to ensure that billets may contact the supporting beam at a very low speed, i.e. possessing the function of "loading and unloading gently". The walking beam will speed up and slower down when it begins and stops moving, thus reducing the impact and shock caused by the walking beam mechanism. The horizontal movement of the mechanism is realized through the following way: its transfer frame is driven by a transfer hydraulic cylinder to get it make transfer movement on the rolling wheel of the lifting frame, at this time, the lifting cylinder is locked in a static state. The vertical movement of the walking beam mechanism is realized through the following way: the lifting cylinder drives the lifting frame to get its rolling wheels roll along the inclined plane to complete the lifting motion, at this time, the transfer cylinder is locked in a static state. The path of motion of the walking beam is shown in the following figure: The walking beam will stop at "1" position ("1" position is the full back and lowest position) before making the cycle movement, the walking beam starts the lifting movement accompanying with speeding up and slowing down from "1" position to "2" position during the cycle movement according to the moving time schedule; the lifting frame will stop when the walking beam reaches "2"point, the walking beam starts the transfer movement to "3" point accompanying with speeding up and slowing down; the transfer frame will stop when the walking beam reaches "3"point, then the walking beam starts the lowering movement accompanying with speeding up and slowing down from "3" position to "4" position, and stops at "4" position slowly, afterwards the walking beam returns "1" position from "4" position, thus completes a positive circulation. When the signal that the rolling mill needs billet is identified(or when the last billet position in the furnace is "vacant"), the walking beam system receives the direction of making positive circulation movement to start lifting, and complete the lifting movement according to requirement of lifting speed control; when the movable beam is lifted upto the right position, the walking beam will move forward under the interlock condition, and the walking beam starts lowering when reaching the full advance position, when the walking beam is lowered down to the position which is 70mm below the discharging roll table level, after the discharging door opens upto the setting position, the discharging roll table will stop and get ready to discharge the billets. The movable beam starts moving backwards after the movable beam is lowered down to the full advance and lowest position (at this time can start charging to meet the requirement of discharging cycle), and stops when reaching the full back and lowest position, thus complete a positive circulation operation. A laser positioning detector is mounted at the discharging end; when the laser detector senses the billets, it will give out a direction, and then the walking beam completes the last step moving to ensure billets to be discharged stops at the right position for the extractor to discharge.The upward and downward travel stroke of the walking beam is 200mm and its horizontal travel stroke is 500mm. the minimum period of motion of the walking beam mechanism is 50 seconds. In normal operation, the walking beam settles at the lowest and full back position. 2.3 Discharging The slabs heated by the furnace shall be discharged as per the requirements of the rolling pace.When heated to the required rolling temperature, the billets shall be conveyed to the discharging end for discharging. If the heat-insulated time of the furnace is very long, it is required that the walking beam stops at the middle position which is of the same elevation with the fixed beam (called middle position holding) or stepping in place to protect billets against bending deformation. When receiving the discharging signal from the level 2 computer of the rolling mill, the control system of the reheating furnace will calculate the travel stroke of the supporting arm of the extractor moves based on the position and dimension of billets settling on the discharging position, the discharging roller outside the furnace stops rotating, the furnace door for discharging is opened, the extractor moves from the its lower place into the furnace, stops at the calculation position and discharge billets, and put billets on the discharging roller table. The discharging roller table then will be actuated to convey the billets to the rolling mill for rolling. At the same time, the extractor returns to its initial position for next discharging. The whole discharging process shall be subject to the monitoring of the high-temperature industrial television mounted at the furnace end head. 2.4 Interlocking Timing, sequencing, interlocking and logic control of billets charging, discharging, counting and material tracing as well as data exchange with the rolling mill shall be achieved with the automatic control system to realize operation automation and level 2 computer management. The interlock relationship among the charging and discharging processes and conveyance inside the furnace is as follows: --When the charging roller table is in operation, billets are still not to be positioned , the pusher will not work; --When there is no Vacant position at the charging end, the pusher will not work;--When the walking beam is at the upper position or moving upward, the pusher will not work. --When the pusher is in charging operation, walking beam is at its lower position and can not work. --When the billets have not been detected by the laser detector at the discharging end, the discharging door is closed or half opened, the walking beam is at its upper position, the extractor can not get unlocked to getting into the furnace. --When the extractor is in discharging operation, the walking beam is at its lower position and can not work; --When the extractor is in discharging operation and the billets are not stable on the rollers, the discharging roller table cannot work; 3 Furnace Plan Layout and Furnace Structure 3.1 Furnace Plan Layout The reheating furnace is located between the Bay B-C and C-D, the span length of Bay B-C is 28m, the span length of Bay C-D is 36m, the center line of furnace coincides with the line of No.7 column. The detail plan layout sees the attached drawing: plan layout drawing 3.2 Furnace Foundation and Structures The civil foundation and structures for the slab reheating furnace of India LSIL Steel include: furnace proper, flue duct, chimney and its foundation, underground hydraulic station, evaporation cooling building (including underground pump station and overground steam drum platform), charging pulpit, distribution room, furnace control room, blower house, equipments foundation, foundation of operating platform, pipe supports and foundation, etc. All above will be designed by the supplier(According to Chinese national standards) and constructed by the Buyer(Including the foundation treatment of above foundation). a. Furnace proper: depth of the furnace pit is -7.5m, the plash depth of furnace pit is -8.5m (deepest point). The ventilation ducts are arranged on both sides of furnace pit along the width of furnace, a layer of RC platform and a layer of steel platform are on the ventilation ducts. On both sides of furnace pit along the length of furnace respectively lay out: the foundation of charging roll table (including sluiceway), foundation of pusher and foundation of discharging roll table (including sluiceway), the foundation of extractor. b. Foundation of flue duct: the bottom level of flue duct foundation is -5.8m, the inner width before recuperator is 5.4m, inner width after recuperator is 5m, inner width at recuperator is8.5m.the requirement of temperature resistance needs to be considered at the foundation of recuperator, the steel plate is covered on the flue duct. In the passing area of charging roll table and slab storage area, the load requirement also needs to be considered. The ramming RC cover plate is selected. c. Chimney: select the RC chimney, the inner diameter of upper port of chimney is Φ3000mm,the height is 80m, the bottom level of foundation is about -8.6m. d. Underground hydraulic station is underground RC ramming structure, bottom level is -7.4m, length × width × height: 9.000x7.000x6.600,a hole is left to cover the grid plate on the top, terrazzo floor, the side wall is interconnected with furnace pit. e. Evaporation cooling platform and water pump room are the RC frame structure, the lower part is water pump room ( length × width × height: 15.000x5.500x6.600), the bottom level in the pump room is -7.4m; the upper part is steam drum platform, its top surface elevation is ± 0 m. f. Blower house: 10.000x8.000x4.500(height), RC ramming frame structure, RC isolated foundation, terrazzo floor, ramming reinforced concrete roof boarding, RC equipment foundation, sliding sash window of double-layer aluminium alloy. g. Charging operation room: 5.000x3.000x4.000 (height), the operation room is made of light steel structure, antistatic floor, the bottom level is +1.5m. h. Distribution room: 13.000x4.500x4.500(height), one-storey brick-concrete cabin, bottom level is +0m, concrete band-shaped foundation, 370 brick wall, terrazzo floor, constructional column, ring beam, ramming reinforced concrete roof boarding, sliding sash window of double-layer aluminium alloy. i. Control room of furnace: 7.000x6.000x4.000 (height), the control room is made of light steel structure, antistatic floor, the bottom level is +1.5m. j. Fuel room: the buyer is responsible for the design and construction of this part. 3.3 Furnace Profile Structure This plan is to build a new walking beam reheating furnace for the medium-wide strip mill , which adopts preheated-air combustion technology and evaporation cooling with forced circulation. As the fuel of the first phase is heavy oil and one year later is coke oven gas, the profile curve of the furnace and burner, even burner arrangement should be compatible to the fuel features. Reasonable furnace profile should be adopted to ensure slab heating quality and production continuity, reducing inspecting, repairing and maintaining time.This design will adopt firing for 4 sections i.e. No.1 and 2 heating section, top and bottom soaking section. And No.1 and 2 heating section will adopt the completely side firing with oil-gas dual fuel burners, the bottom soaking section will still adopt side firing with oil-gas dual fuel burners. And the top soaking section will adopt end firing (arrange oil-gas dual fuel burners along the width of furnace), so that ensure a good temperature uniformity within the width of furnace, the simple furnace profile and good operation condition. The height of upper hearth of heating and soaking section is 1800mm, that of preheating section is 900mm, height of bottom hearth for all sections is 2200mm. According to the plan layout of the furnace, the reheating furnace adopts upper flue discharging method at the end of the furnace tail. The furnace will adopt end charging and discharging. 3.4 Major Dimensions of Reheating Furnace Distance between Center Lines of charging and discharging roller table ----------- 40000mm Effective length of reheating furnace------------------------------------------------------------ 34600mm Width of masonry of reheating furnace---------------------------------------------------------- 12864mm Inner width of reheating furnace ------------------------------------------------------------------11800mm Elevation of top surface of charging roller table ---------------------------------------------- +900mm Elevation of top surface of discharging roller table---------------------------------------- +900mm Depth of furnace pit ----------------------------------------------------------------------------- -7500mm 4 Technical Specifications of Equipment and Facilities of The Reheating Furnace 4.1 Steel Structure of The Furnace Body The steel structure of the furnace body is a weldment made of plain carbon steel plate and a variety of steels, and it is used to install and support the refractory material of the furnace, to support the bottom beam of the furnace, to install the burners, furnace door and accessories on both sides of the furnace, equipments and pipes of combustion system, and to install maintenance platform of meter automation etc.. The steel structure of the furnace body contains the steel structure of the hearth, the steel structure of the side wall, the steel structure of the end wall, the steel structure of the furnace roof. All these parts form a box frame structure. 4.1.1 Steel structure of the hearth The bottom steel structure consists of three parts: the bottom frame and steel plate, bottom longitudinal girder and steel columns. The bottom frame of the furnace is formed with I beam, channel steel and steel plate by welding, and it's used to support the masonry materials on thebottom of the furnace and install fixed column. There are also openings for the movable columns and seal case for fixing and sealing the furnace. The bottom steel longitudinal girder runs through the overall furnace length of the hearth to support the bottom frame. The column is made of H-section steel and steel plate, its function is to support the bottom longitudinal girder. 4.1.2 Steel structure of the side wall The steel structure of the side wall is a frame structure which is welded with I beam, channel steel and steel plate. The lower part of it is fixed by bolts in the bottom steel structure of the furnace, and the top is connected with channel steel gird beam to form a rectangle frame. The accessories of the furnace, such as burner of the furnace, side furnace door, access door, industrial TV, laser detector and peephole, are all fixed on the steel structure of the furnace wall. 4.1.3 Steel structure of the end wall The steel structure of the end wall is welded with I-section steel, channel steel and steel plate. The lower part of it is fixed by bolts in the bottom steel frame. The charging and discharging door and its driving device are installed on the head end of the steel structure. 4.1.4 Steel structure of the furnace roof The main part of the steel structure of the furnace roof is the cross beam which is made of hot-rolled H-section steel. The hanging beam of furnace roof anchor brick hangs on the lower flange of the H-section steel, and the two ends of the cross beam of the H-section steel stand on the ring beam of upper steel structure (the steel structure of the side wall). To maintain the integral stability of the H-section steel, a certain amount of reinforcements between the top and lower flanges are configured. 4.1.5 Platforms, stairs, railings Movable steel plate platforms on both sides of furnace Concrete platforms leading to the hearth on both sides of furnace. Steel plate walkways leading to the control valves and burners in each section. Stairs at the connection of diversed platforms and walkwaysRailings on the margin of platform and walkwayFully consider the multiple factors, such as appearance, safety operation. 4.2 Masonry Structure of Reheating Furnace The properties of the reheating furnace depend to a great extent on the selection of refractories and its use condition;The furnace wall adopts integral pouring construction with complex lining; The furnace roof adopts integral pouring composite with castables; The hearth adopts mold brick composite laying; All the designs ensure that the average temperature of the external surface of the furnace roof except for burner area is no higher than 120oC and the temperature of the external surface of the side wall is no higher than 105oC; The holes on the bottom of the furnace, which supporting beam and walking beam go through, are constructed with castables. The structural design and material selection for the furnace body (except for special positions such as water pipe packing at the bottom of the furnace) shall secure the overall service life of the furnace body not less than eight years. Refractories selection for various parts of reheating furnace: Table1: Table of Masonry Structure Selection Laying PositionMaterial NameThickness (mm)HearthHigh aluminum brick116Fireclay brick270Light weight fireclay brick γ=1.0136Thermal insulating plate70Total thickness 592Furnace Walllow cement castable250Light weight fireclay brick γ=1.0116Light weight fireclay brick γ=0.8116Thermal insulating plate50Total thickness 532Furnace Rooflow cement castable230Thermal insulating plate60Expanded perlite60Total thickness 350Thermal InsulationSelf-flow pouring material 60Section of Supporting Beam and PillarAluminum silicate fiber blanket RT20Total thickness80Flue Duct before The Recuperatorfireclay brick116Light weight fireclay brick r=1.3116Fiber blanket50Total thickness282Flue Duct after The RecuperatorLight weight fireclay brick r=1.3116Fiber blanket50Total thickness166External Insulation for Hot Air PipelineFiber blanket60-80Galvanized iron sheet0.5Total thickness60.5-80.5Internal Insulation for Hot Air PipelineLight weight fireclay brick r=1.3116Fiber blanket30Total thickness146External Insulation of Evaporative Pipelinepipeline slag wool or glass wool (shell and tube products)60Heavy Oil and Heat Tracing Pipelineslag wool or glass wool (shell and tube products)60Steam Atomizing Pipelineslag wool or glass wool (shell and tube products)604.3 Supporting Beam and PadTo support and convey the billets, we install five fixed beams and four walking beams; The walking beams go through the bottom of the furnace by the posts and is fixed on the transfer frame, and the fixed beams together with the posts are supported and fixed by the steel structure of the bottom of the furnace. The skid is divided into 3 sections within the full length of furnace. The fixed, movable beams and their double-posts all adopt Φ140×20 seamless dual-tube construction, the single-post of fixed beam adopts Φ140×20 seamless tube, and single-post of movable beam adopts Φ194×20 seamless tube. The post of the supporting beam adopts casing structure. The outer tube adopts hot-rolled thick-wall seamless steel tube,and the inner tube adopts normal seamless steel tube .Thelongitudinal beam is welded with T-joint the top of the post. The post tube is connected to the longitudinal beam with rigid welded construction. To maintain the vertical stress of the longitudinal beam to the post tube when the furnace is in working condition, the swelling capacity of the longitudinal beam during heating is taken into consideration when installing the post tube. The skid post adopts double-layer thermal insulation packing to strengthen the thermal insulation effect. To decrease the "low temperature black mark" at the contact position between the heated billets and skid, heat-resisting pads, which are of a variety of materials, are installed at the different temperature sections between the billet and skid of the reheating furnace. This can eliminate the "low temperature black mark" at the contact position between the heated billets and skid and can reduce the difference of the temperature between the contact position and the surface of the billets laid between the two supporting beams. The heat-resisting pads of skid in different sections shows as below:Table2:The Schedule of Heat-resisting Pads of Skid in Different Sections PositionMaterialHeightWidthPreheating SectionCr25Ni20Si270mm40mmHeating SectionCo2070mm50mmSoaking SectionCo40100mm The contact surface temperature between top surface of 100mm-high Co40 pad and billet can reach up to 1100oC,which is close to the discharging temperature. So the effect of the "water pipe black mark" is less. The structure of pad adopts optimal type and quantity to minimize the pressed mark of pad, so that accommodate the requirement for the slab heating. The fixed beams in soaking, heating and preheating zone adopt staggered arrangement to avoid the "skid mark" effectively. To ensure the heat exchange between skids and pads and increase the service life of pads effectively, the directly welded structure will be adopted for the pads and skids. 4.4 Water seal trough and scale removal system The walking beam post runs through the furnace bottom, and is fixed on the transfer frame. In order to seal the holes on the movable post and the furnace bottom, a water seal trough is set at the lower part of the walking beam and is fixed on the transfer frame. Part of the small amount of scale produced by heating the slabs in the furnace enter into the water seal trough through the opening of the furnace bottom, be delivered to the charging end by the scraper fixed on the bottom steel structure with the movement of the walking beams, be collected into the pit slag hopper, and then craned away by the crane through the hoisting hole. The post of the walking beam goes through the bottom of the furnace and fixed on the transfer frame. Long-round hole was opened in the bottom according to the translation distance of the walking beam. In order to prevent the cold air from being sucked in the furnace, the water seal trough was designed between the steel structure in the bottom and the translation frame, apron-type water seal blade is also designed between them to insert into the water seal trough to seal. As the post tube goes through around the opening of furnace bottom, an enclosure wall above the furnace bottom shall be rammed with the castable to prevent furnace slag from dropping into the water seal trough. Since a small amount of scale drops into the water seal trough, a scraper is mounted under the apron water seal blade, in this way the scale will be automatically scraped to the charging end of the furnace tail in the lifting and moving process of the walking beam. The water seal trough and the scraper at the furnace tail end are lifting gradually, which may get the scraped scale dried and scraped into the slag chute at the furnace tail end and slag be carried away periodically. The water seal trough and the scraping plate shall be made of the steel plate, and the internal surface of the trough shall be painted with phenolic resin. 4.5 Furnace Door and The Observation Hole 4.5.1 Charging door The charging furnace door adopts the welded structure of profile steel and steel plate, with two furnace doors, which can be operated synchronously or respectively. They adopt non-water cooling, integral casting structure. The furnace door on left and right side are equipped with a hydraulic lifting device individually. 4.5.2 Discharging door The furnace width direction is formed of two furnace doors (left and right) which can be operated synchronously or respectively with each furnace door has a water-cooling system, constructed from welded profile steel and steel plate, with the inner lining castable. Each furnace door is equipped with a hydraulic lifting device. 4.5.3 Sight hole There are six sight holes set on the side wall of the reheating furnace for observing conditions in the furnace and burner flame, mounted on the level of fixed beam with a shelter plate and a high temperature glass observation hole. 4.5.4 Access door There are four access door set on the side wall of the reheating furnace for passing in and out of the materials during the maintenance, and is convenient for the test and laying the temporary dry-out pipe during drying out. The access door is sealed by loose face masonry with refractories, and a steel plate door is mounted outside. 4.6 Combustion System of Reheating Furnace The reheating furnace will use the heavy oil in phase 1 (within 1 year after putting into production) and coke oven gas in phase 2 (1 year later after putting into production) as the fuel, therefore the design of reheating furnace has to be suitable for this kind of condition to satisfy the using of reheating furnace in phase 1 and 2, and not effect the life of furnace body, so that the furnace shutdown time for secondary reforming is short and the reforming cost is low. The combustion system of reheating furnace mainly includes: oil and gas dual-fuel burner, heavy oil system in phase 1 (including steam atomizing, heat tracing, purging), coke oven gas system in phase 2 (including nitrogen purging, bleeding system), combustion air system, flue duct system, chimney and ignition heating system. The ignition heating system is needed for the first time dry-out and restarting the furnace each time in phase 1 when using the heavy oil as the fuel. 5 Mechanical Equipments in Reheating Furnace Area The mechanical equipments in the area of reheating furnace mainly consist of charging roller table and discharging roller table within the range of furnace width, pusher and extractor, charging/discharging furnace door and their elevating mechanism, hearth walking machinery, hydraulic system, grease centralized lubrication system etc. 6 Evaporation Cooling System and Thermal Facilities of Reheating Furnace For the slab reheating furnace provided to Indian LSTL steel plant, evaporation cooling and forced circulation are adopted for skid cooling. The designed rated cold charging capacity of reheating furnace is 250t/h. Evaporation cooling is adopted for horizontal beam and post of walking beam reheating furnace. The beam and post are pipe structure, which can bear high pressure. steam parameters: pressure of input steam 1.27MPa temperature of input steam 190oC The cooling capacity of vaporization cooling system is designed according to the following conditions: Heat preservation system falling-off of skid of whole furnace max.10% Heat preservation system falling-off of skid of single cooling loop max.40% Heat preservation system falling-off of post of single cooling loop max.10% 7 Level-1 Automation Control System (1) System Overview The slab walking beam type reheating furnace has high requirements for response speed and resolution of the control system. In order to guarantee the test control accuracy of the walking beam and reduce the tracking error of billets from charging to discharging. According to our experience, the electrical control system has strict requirements for control cycle of PLC analog quantity, resolution of analog quantity and sampling refreshing cycle. Therefore, the software design must be optimized so as to guarantee failure-free operation of the system while high-speed PLC is adopted. The control of analog quantity of reheating furnace instrumentation system is comparatively complex, while the control of switching value is relatively simple. So, with regard to the instrument control, the DCS system should be adopted. With regard to the reheating furnace that is comparatively independent, the control system should be simplified as much as possible, so as to share resources and reduce costs. The reasonable scheme is to adopt an electrical and instrumentation integrated system. a)Two sets of control system devices shall be set up for each reheating furnace of the whole basic automation system. Electrical control system will use one set of PLC system , which is used for the control and material tracing of reheating furnace proper equipments and charging/discharging furnace door; the other DCS system is used for combustion control and vaporization cooling system. b)Three HMI stations shall be adopted for the reheating furnace control system. One engineerstation shall be set up in the reheating furnace control room by the electric system to observe the blank operation and tracking inside the furnace; the parameter setup, operation, state display, error supervision, alarming and report printing shall be carried out through the LCD picture, and at the same time the sigils shall be transmitted to the DCS operating room through communication; the other 2 HMI stations are also set up in the operating room in the furnace area to control the combustion system and evaporating cooling system. c)The I/O configuration of the control system should be reserved for 10 over measure. d)The control system and the primary instrumentation are set on the linear UPS, with the working time with not less than 30-minute delay. (2) Hardware Configuration of Level-1 Automation Control System One set of PLC system shall be equipped for the electric control of reheating furnace proper, which mainly controls the charging furnace door, discharging furnace door, walking beam and hydraulic station etc. The S7-300 device shall be adopted and its configuration is as follows: 5A power template PS307 Central processor CPU315-2DP Counter Module FM350-2 Analog quantity output module SM331 Digital input module SM321 DC24V×DI32 Digital output module SM322 DC24V×DO32 Communication The entire system sets up two layers of communication buses: DCS system adopts the SINECHI of Ethernet to progress communications and driving PLC systems aopts the on-site bus PROFIBUS to progress communications. DCS system progresses data communication with driving PLC system through its DP communication template. Driving devices progress communication using the on-site bus PROFIBUS; meanwhile connecting with rolling line Ethernet to progress data communication.(3) Main Electric Application Function of Base Automation System a)Survey of equipment acting process After the slabs which complete length-measurement, width-measurement, ID identification enter onto roller table, the slab will be positioned along the width of furnace; When the charging conditions are satisfied, the charging door will open, the pusher will push the slabs on the preset position of fixed beam in furnace in accordance with the calculated stroke. With the movement of walking beam, the slabs will pass No.1 heating section, No.2 heating section, soaking section in turn, and will be fully heated upto the expected discharging temperature to wait for discharge at any moment. When there is the request to discharge, the discharging door will open, the extractor will extend into the preset position in furnace according to the calculated stroke and lift up the heated slab, the slabs are pulled out and placed on the center line of discharging roller table, at the same time the extractor will return to the initial position to wait for next action. During above charging and discharging process, the operation status, electrical fault, equipment malfunction of all electrical-control equipments shall be monitored on line by electrical control system, and make the alarm classification by major error and minor error, and prompt by means of sound/light alarm, then print out the record of alarm type. b)Main control functions of the primary sequence control of the reheating furnace --Main functions of sequence control of reheating furnace: Setting of travel distance of charging and discharing machine Control of charging and discharging furnace doors. Setting and control of the travel stroke of walking beam. Control of positive cycle, reverse cycle and middle holding of the walking beam. Detecting and control of discharging locations of slabs.Tracking of slabs in the furnace area.Control of hydraulic station and lubrication station.Interlocking among all devices in the furnace area. --Functions of workstation (HMI) Running preparation Parameter setting and operation Running monitoring Fault monitoring and alarm Simulation running of equipment Log and saving Report forms printing Data communication between level-1 sequence control system of the furnace area and other relevant system (4) Operating Mode There are three operating modes: automatic, semiautomatic and manual. Automatic: various working sequence and operations and interlocks between the devices will be automatically carried out in accordance with operational conditions of various mechanical devices. All controls will be set up through the computer and carried out by the basic automation system. Semiautomatic: the working sequence of partial single devices will be carried out by themselves, and the interlock relationships between devices and the starting order to operation will be given by operators, and its controls will be accomplished by the basic automation system. Manual: the single operations are carried out by the operator through the operating desk and operating cabinet, especially emergency operations when the machinery is in repair or failure. (5) Operating Equipment and Detector a)Operating desk Main operating desk of the reheating furnace (adopted material is stainless steel and high quality components) is placed in the operating room of the reheating furnace system, including the operator station used for installation of primary control system and the operating elements used for installation of hardware. b)Site control box It is used for side operation of hydraulic devices,walking beam,fan and drain pumps in pit of the reheating furnace, to satisfy the requirements of maintenance and debugging. c)Detecting element Main detecting elements, such as pulse coder, linear displacement transducer, etc., adopt the high quality products. Detecting element of reheating furnace --2 linear transducers, used for furnace bottom machinery; --2 laser detectors, used for width verify for charging slabs and detecting the position for discharging slabs. (6) Other Electrical Devices a)Lighting distribution box The C65N circuit breaker is installed inside; and the lighting power supply is from the lighting distribution box in the reheating furnace area, used for hearth lighting. b)Examining power cabinet and power boxFour examining power cabinet shall be set up in the site of area of reheating furnace. The power shall be provided by the customers for distribution of all examining power boxes in the area of reheating furnace. One three phase 415V socket, two single phase 230V sockets, one suit of three phase 415V connecting terminals of electric welding machine are installed inside the examining box. The leakage protecting circuit breakers are installed in all return circuits. 7.1 Combustion Control System: 7.2.1 Summary Combustion Control Instruments DCS various test items to complete the circuit control, data acquisition, data processing, operator station stoves needed for the production of all operations, and monitoring of parameters, including overall and packet flow screen, circuit adjustment and display, fault alarm screen, instantaneous images and historical trends, fault alarm printing, parameters printing and production table printing etc. 8 Technical Performance Sheet of the Walking Beam Reheating Furnace Usage of furnace:heating the slabs before rolling Type of furnace:top & bottom fired walking beam type reheating furnace Heating steel grade: low carbon steel,medium carbon steel, including pipeline steel C-60 and X-70 Dimensions of billets: Length: 4.5~11m ,Width: 900~1270mm,Thickness: 200,210mm The proportion of billets: A) 4.5 meter length slab charging: Maximum 5.0% B) 6.0 to 8.0 meter length slab charging: Maximum 5.0% C) 11.0 meter length slab charging: 90% We can know from the charging diagram, the billet size of 7-8m is not suitable for chargingCharging temperature:cold charging, room temperature, completely hot charging 600~900oCdischarging temperature 1250±30oC Production capacity: Rated output is 250t/h ( cold charging, room temperature, 210 mm×1270mm ×11000mm,common carbon steel, discharging temperature 1250oC) Rated output is 300t/h ( completely hot charging, 600 ~ 900 oC×11000mm, common carbon steel, discharging temperature 1250oC) Fuel and low heat value:Heavy oil with heat value of 10200 Kcal/kg Heating mode:No.1 & No. 2 heating zones and bottom of soaking zone will adopt side heating, the top of soaking zone will adopt end heating, totally divided into 4 zones to control. Rated Specific Fuel consumption: 1.35GJ/t ( Rated output, carbon structural steel, cold packed, standard blank, stable production, new furnace lining, stable quality of heavy oil , steel billet discharge temperature~1250oC)scale loss: 0.8% ( Rated output, carbon structural steel, cold charging, standard billet, stable production, new furnace lining, the quality of heavy oil satisfied the requirement, steel billet discharging temperature~1250oC)Air preheating temperature : 480 oC ( when flue gas temperature before recuperator is 800oC) Stepping machinery type: two wheels on slop rail, hydraulic drive Stepping lifting travel stroke 200mm Stepping translation travel stroke 500mm Stepping period 50s Company ProfileCompany ProfileVisionWith decades of rapid development and accumulation, China has been perfect and mature on technology and management in various industrial areas, shaping a complete processing manufacturing industry with competitive price, well known for its excellent skill, high efficiency and hardworking team with qualification for personnel dispatching.At the time of economic globalization, it is our consistent target and objective to integrate and export all kinds of technology, management mode, engineering project and manpower as per the actual requirement of our client With our own abundant technical strength, superior integration capability of technology and resources, well experienced of project implementation and management as basis and platform;Let China go out to the world, and make the world know of China; ProfessionalProfessional technical and management team with abundant experience in the implementation of domestic and international projects;ResponsiveResponsive care translating your needs into complete solutionsIntegrationIntegrating various technologies and resources in China and fulfilling complementary advantages by relying on professional teamsMotivationMotivated to provide optimal solution and quality productsExceptionalExceptional project delivery and execution meeting your expectationsOur TeamProfessional technical teamPrime is staffed with professional import & export team skilled with the practice of import and export business, including sea freight packing, logistics organization, L/C review, cargo booking, and customs clearance, L/C negotiation, double authentication of shipment documents, etc.All above personnel are well experienced in the execution of projects in Southeast Asia and Middle East. Complete procurement mechanismOur professional team of procurement offers strict management of supplier 's qualification inspection and selection, complete system of supplier listing, rating and elimination, to ensure the supplier is qualified and capable of implementing the project and supplied with product of high quality, and maintain a healthy and good condition of credibility, contract settlement and capital flow management.Quality management systemOur complete quality management system , the process control covering from Scheme formulation , engineering technology, detailed design, to processing and manufacturing of equipment and material , ex-factory test and site erection and commissioning till it put into production, which through multi-level inspection, tour inspection, supervision and node control can ensure quality of the final product.Well experiencedExecutive team is abundant in experience of overseas project implementation with similar project working experiences, esp. experience in Southeast Asia, Middle East projects; ISO System Certification Partners

× More Keyword ..

× More Menu ..

×

Manufacturing & Processing Machinery

×

Industrial Equipment & Components

×

Tools & Hardware Products