2. Process and composition and description of homogenizing furnace group
1. Process flowStorage: The crane will hoist the modified aluminum alloy round ingot to be processed on the soaking tray of the storage platform;
Furnace loading: The three-dimensional composite loading and unloading truck starts to load the unloading pan from the storage platform, and then drives the truck to run to deliver the pan to the furnace door, and at the same time the furnace door is lifted in place, and the furnace door is securely locked; the feed truck enters the furnace, The lifting device is lowered, the tray is steadily placed on the bracket in the furnace, the charging car is withdrawn, and the furnace door is closed and reliably sealed;
Soaking: After the furnace door is closed, the soaking furnace will automatically quickly heat up and keep warm according to the set soaking process curve. During the heat preservation process, the temperature difference of each point in the furnace is ≤5℃;When the furnace gas temperature reaches the set temperature, the circulating fan can automatically switch the speed according to the process requirements to ensure the uniformity of the furnace temperature;When the furnace enters the heat preservation stage, the number of burners or fuel supply is automatically adjusted to meet the requirements of furnace temperature uniformity.Out of the furnace: After the soaking process is completed, the charging car is driven to the door of the soaking furnace, the furnace door is safely locked after it is raised in place, and the charging car enters the furnace and starts to take out the material pan and drives it to the cooling chamber;
Cooling: the material truck runs to the door of the cooling room, the door is opened, the material truck enters the cooling room, and the hot material tray is placed on the indoor material rack, the material truck exits, the door is closed, and the rapid cooling system is activated to quickly cool the aluminum alloy round ingot. When the ingot is cooled to the set temperature required by the process, the air slow cooling method is adopted, that is, the outdoor air enters the cooling chamber through the fan to cool the aluminum alloy round ingot, and the hot air is discharged by the exhaust fan;
Unloading: After the cooling of the aluminum alloy round ingots is completed, the material truck automatically enters the room to take out the material pan, waiting for unloading, after unloading, the crane will store the material and start the next cycle.
2. Main technical parameters and technical performance
2.1 Soaking chamber:
2.1.1 Purpose: Soaking of aluminum alloy round ingot
2.1.2 Quantity: 1 set
2.1.3 Alloy varieties: 1---7 series
2.1.4 Furnace load (net weight of round ingot): ≥30 tons.
2.1.5 Maximum length of ingot: L=6500mm
2.1.6 The highest temperature of the furnace: 630℃
2.1.7 Working temperature: 420～620℃
2.1.8 Temperature uniformity of working area in furnace: ≤5℃
2.1.9 Fuel: natural gas, pressure 7-9Kpa, calorific value 8500Kcal/NM3
2.1.10 Temperature control mode: automatic, display, record, alarm
2.1.11 Loading and unloading: the three-dimensional composite loading and unloading vehicle automatically loads and unloads, and it is shared with the cooling chamber
2.1.12 Furnace outer wall temperature: ambient temperature +25℃
2.1.13 Noise: ≤85dB(A) (1 meter away from the furnace body)
2.1.14 Thermal efficiency: ≥55%
2.1.15 Heating rate: ≥200℃/h 2.1.16 Energy consumption: 26-283/ton·
This value refers to the energy consumption of 6 series alloys at 570°C for 4-6 hours, and the energy consumption is obtained under continuous production (other alloys can be set according to customer requirements).
2.1.17 Ignition medium: natural gas.
2.1 Cooling room
2.1.1 Purpose: rapid cooling of aluminum alloy round ingots
2.1.2 Quantity: 1 set
2.1.3 Loading capacity: ≥30 tons.
2.1.4 Cooling method: forced air cooling + water mist cooling.
2.2.5 Cooling rate: ≥350℃/h
2.2.6 Cooling water consumption: 12t/h (for aluminum rod water mist cooling)
2.2 Three-dimensional composite loading and unloading truck
2.2.1 Purpose: Transportation of aluminum alloy round ingots and trays
2.2.2 Quantity: 1 set
2.2.3 Loading capacity (net weight of round ingot): >40 tons.
2.2.4 The accuracy of the rail alignment of the feeder: automatic
2.2.5 The speed of the horizontally running cart: 5.0~15m/min (hydraulic transmission)
2.2.6 The speed of the trolley running longitudinally: 5.0~10 m/min
3. Technical terms
1.30 tons of natural gas-fired homogenization furnace
1.1 Technical parameters; (Finally according to the actual design as the standard)
wMaximum tonnage 30-35 tons
wOutput about 120 tons/day
wThe inner length of the furnace is 6800mm
wFurnace height 2900mm
wThe height from the ground to the material table 1130mm
wWhen opening the door, the width of the furnace mouth is 2510mm
wMaximum feeding width 2250mm
wMaximum feeding height 2400mm
wMaximum feeding length 6500mm
wFurnace limit operating temperature 630℃
wNumber of control areas 6
wNumber of circulating fans 3
wFan air volume ≥22 cubic meters per second
wMotor power 55 kW
wNumber of burners per zone 3/1
wTotal number of burners 12
wTotal furnace power 1.3×106 kcal/h
wFurnace temperature control accuracy <5℃
wEnergy consumption 26-283/ton·aluminum
This value refers to the energy consumption of 6-series alloys at 580°C for 4-6 hours, under continuous production.
Soaking temperature range: 430～610±5℃ (the temperature is air temperature and metal temperature)
The time difference between the casting rod temperature at each point in the furnace to the required homogenization temperature should be ≤2 hours. If the set temperature is 600 degrees, the time difference between each point in the furnace to 595 degrees should be ≤2 hours, and so on.
1.2 Heating method:
After the aluminum rods are loaded, they are sent into the homogenizing furnace through the charging truck, and the circulating fan starts to circulate the air in the furnace to make the temperature uniform. After the 9 burners on the top side of the furnace are ignited by the ignition gun, the air in the furnace is heated, and the air is circulated. The aluminum rod is heated up. The microcomputer controls the temperature and temperature rise mode by automatically controlling the switch of the burner and the size of the firepower through the signal of the temperature measuring thermcouple. PLC has more than 40 heating modes that can be stored.
1.3. Circulating fan
The circulating fan is installed on the side of the furnace body, driven by a 45kw motor through a V-belt, and it is low speed at low temperature and automatically turned to high speed at high temperature to ensure uniform temperature in the furnace. The fan is made of heat-resistant stainless steel. When the furnace door is opened, the burner and the circulating air machine will automatically stop. The material of heat-resistant stainless steel is 304. Fan temperature resistance: 800°C (a temperature-blocking ring is added in front of the bearing seat to increase the service life of the bearing).
The deflector is made of stainless steel. The function of the deflector is to make the hot air evenly flow through the aluminum rod and make the temperature uniform. Stainless steel material 304.
1.5. Furnace structure
The furnace shell is welded by section steel and steel plate, the inner layer is stainless steel plate, and the stainless steel plate is passed through stainless steel screw. The bolts and nuts are fixed, the furnace side and the furnace roof are filled with 300mm thick refractory fiber cotton, and the bottom of the furnace is made of 290mm thick refractory bricks and insulation bricks (the bottom layer is 60mm fiber cotton, and the thickness of the diatom insulation brick in the middle is 115mm, the thickness of the upper clay brick is 115mm), the inner side of the steel plate is covered with a layer of 10mm nanoboard to ensure the heat preservation performance of the furnace. There are steel rails and a receiving platform in the furnace to ensure that the feeding cart can enter and exit freely and the material is stable.The steel structure materials are as follows: (all steel materials are allowed to have negative tolerances due to the relationship between the manufacturers, but this tolerance needs to comply with the relevant national standards)
1.1.1. Furnace top 20# channel steel and 6mm steel plate.
1.1.2. 16# channel steel and 6mm steel plate on the back wall of the furnace.
1.1.3. Side wall 16# channel steel and 6mm steel plate.
1.1.4. Fan side wall 16# channel steel and 10/6mm steel plate.
1.6.6. Front wall and lifting frame 320# channel steel, 160×160×10 angle steel, 80×43 channel steel,
80×80×5 angle steel and 6mm steel plate.
1.1.6. Furnace door 14# channel steel and 6mm steel plate.
1.1.7. The steel rail in the furnace is 38kg/m.
1.1.8. The supporting table in the furnace is Φ165×14 steel pipe and 20mm steel plate.
1.1.9. The thickness of the lining stainless steel plate is 2mm (national standard, the material is 304).
1.6. Furnace door device
The outer layer of the furnace door is welded by section steel and steel plate, the inner layer is stainless steel, and the inter layer is 230mm refractory fiber. The furnace door is lifted by an electric mechanism, and the motor is equipped with a brake. In order to ensure air leakage, the furnace door is equipped with a clamping mechanism, which is realized by the action of a cylinder. When the cylinder is opened, the furnace door can be lifted, and the furnace door is limited by guide rails, and it stops automatically when it reaches the upper and lower positions. The sealing material is refractory fiber asbestos rope. The furnace door system and the combustion system realize interlocking control.
1.7. Combustion system:
The homogenizing furnace adopts high-speed burners for heating and temperature control in 6 zones. After charging, the furnace is heated with a certain load for a period of time to reduce the expansion rate of the furnace. Then switch to full-load heating, and shut down one burner in each zone when the limit temperature is reached. After turning to the temperature control stage, shut down another burner. Finally, the remaining two burners control the temperature. Because the flame is sleepless adjustable, the control Temperature is accurate. When the furnace temperature drops to the point that the two burners cannot control the temperature, the other burners will be automatically ignited. The entire combustion system consists of a fan, air duct, high-pressure ignition system, pressure gauge, solenoid valve, air/gas proportional valve, etc. The entire combustion system is automatically operated by PLC. The heating mode can be changed by changing the program. The heating mode can be carried out in stages, such as raising to a set temperature and holding it for a period of time, and then raising to a set temperature and holding it for a period of time. This process To automatically operate according to the set mode. The combustion system should be equipped with a natural gas meter (provided by the customer) with an accuracy of 0.5.
1.8 Smoke exhaust system
The chimney is used for direct exhaust, and the exhaust gas is discharged after heat exchange by a heat ex-changer.
1.9 Homogenizing furnace is equipped with explosion-proof device.
1.10. Electronic control system
In order to accurately control combustion and ensure safety, the electronic control system provided by the seller will all be installed in the electrical cabinet. The combustion system is controlled by a microcomputer in the electric cabinet. When the control fails, the over-temperature will automatically stop, and it is equipped with a temperature recorder. The entire electric control system is composed of indicator lights, buttons, alarms, switches, circuit breakers, insurance, etc. The entire electronic control system has been installed in the seller’s factory. The PLC is Siemens S7, and the touch screen is 10.2 inch Kunlun ON state. The 6-channel temperature recorder can record the data of the air temperature in the furnace with paper. The recorder can record the data for a certain period of time. The record content includes: channel number,temperature, date, time.
2.30 tons of cooling chamber
2.1. Technical parameters30 tons
Furnace length 6500mm
The width of the furnace when the door is opened is 2510mm
The inner height of the furnace door 2900mm
Height from ground to material table 1130mm
Number of axial fans 22 (according to the final design)
The air volume of each fan is 0.6 m3/s
Motor power 2.2 kW/unit
Cooling time Approximately 1.5-2 hours to cool down to below 120 degrees and out of the oven.
Cooling rate ≥350℃/hour
Power supply 380V 3 phase 50hz
Control power supply 220V single phase 50hz
Cooling water consumption ≈12m3/h
2.2. Cooling chamber structure
The section steel is welded to the steel plate to form the furnace body, the furnace body is connected to the foundation through the embedded bolts, and the cooling chamber is a steel concrete structure.
The steel structure materials are as follows: (all steels are allowed to have negative tolerances due to the relationship between the manufacturers) 2.2.1. Furnace top 16# channel steel and 6mm steel plate.
2.2.2. Furnace back wall, front wall and lifting frame 20#, 16# channel steel and 6mm steel plate.
2.2.3. Side wall 16# channel steel, 63×63×5 angle steel and 6mm steel plate.
2.2.4. Fan side wall 160×65 channel steel, 100×63×8 angle steel and 6mm steel plate.
2.2.5. The furnace door is 50×37 channel steel and 3mm steel plate.
2.2.6. The steel rail in the furnace is 38kg/m.
2.2.7. One cooling chamber adopts single door; 2.2.8. The cooling chamber air duct is made of 3mm steel plate;
2.3. Electronic control system
The electric control system is composed of starters, buttons, indicator lights, etc. The temperature sensor automatically controls the fan, and the start and stop of the water mist are operated by human hands. The cooling temperature can be set on the thermometer. Cooling water pipe and booster water pump. 2.4. Cooling process
The design principle of this system is to cool the cast rod at a cooling rate of 350°C/hour without bending.