Development and Application of the First Highly Efficient Interlocking Constant Velocity HND-4000L Kneading Pot

Feng Guosheng Zhu Youliang

(Hebi Coal Machinery Equipment Manufacturing Co., Ltd., Hebi, Henan 458000)

Abstract : Aiming at the requirements of aluminum carbon kneading process, the HND-4000L mixing and kneading equipment with high efficiency, full area heating and intersecting is used to research and develop the HND-4000L mixing kneading equipment suitable for the carbon market. The whole chassis and the special agitator using Japanese Panasonic technology are used for the hydraulic system. The optimized design adopts SIEMENS PLC automatic control. The equipment is more stable in operation, more reliable in performance, and the product quality and various performance indicators are improved, which is of great value for promotion.

Keywords: carbon kneading equipment development and application

I. Question raised

With the rapid development of domestic and international electrolytic aluminum production, and the need for further expansion and high-quality production of prebaked anode carbon for aluminum, new proposals have been made on how to properly control the kneading temperature and the kneading time for the optimal kneading effect of the aluminum carbon kneading process. Subject.

Our company is a mechanical equipment manufacturing company under the Henan Coal Chemical Group. It was established in 1958 and has a history of more than 50 years. Since May 1982, production demand has accumulated rich experience in the manufacture of carbon equipment. It has designed and manufactured several 500L~4000L steam or heat-conducting oil heating kneading pots for the carbon industry. 82 years ago series of mixed kneading pan products in more than 20 provinces and cities across the country, in Henan, Hebei, Shandong, Shanxi, Shaanxi, Hunan, Xinjiang, Fujian, Guangxi, Yunnan and other provinces, the share of more than 70%.

A total of 31 carbon plants in Sasin, Chenzhou, Wanfang Carbon and Zhengzhou Qiangqiang Carbon Co., Ltd. in Zhengzhou used 85 2000L mixing kneading pots.

The Olain Yongxing Carbon Company in Texas uses 12 sets of 3000L kneading pots, and 13 carbon plants such as Shandong Zhongxing Carbon Company use 56 sets of 3000L kneading pots.

11 carbon companies such as Longkou Donghai Aluminum Company and Binzhou Weiqiao Aluminum Company used 36 4000L kneading pots designed by the Shenyang Institute.

In 2006, we conducted technical cooperation with Guiyang Aluminium Magnesium Design Institute, combined with our company's experience in mixing kneading pots, and jointly designed and developed a new HND-4000L hot kerosene heating mixing kneading pot adapted to the needs of the carbon market. In addition to the current advantages of current equipment at home and abroad, we have made major improvements to the equipment structure. We have adopted a special hardened gear reducer with an integral chassis and double-outlet space for two-dimension force flow, using special mixing blades from Panasonic technology in Japan. The cross section of the shape and the egg row, the wear-resistant arc lining, the improved unloading door and the optimal design of the hydraulic system. The new HND-4000L horizontal dual-agitator hot kerosene heating kneader is more stable and reliable, and the product quality and various performance indicators can be improved.

Second, the technical performance of equipment and parameters: HND-4000L mixing pot

1, the volume

Total volume: 5800 litres

Effective volume: 4000 liters

2, material handling capacity

The maximum material handling capacity: 4500 kg

Minimum material handling capacity: 3,800 kg

3, mixing blade form and speed

Horizontal double-shaft intersecting arrangement of Z-type agitating blades, stirring speed dual axis synchronization 12 rev / min

4, heating medium: (pot body and bottom opening two parts)

Heated oil heating pan and bottom door

(The bottom of the pot body is hydraulically driven to open the door by flipping, with the top tighter.)

Working pressure: <0.5 MPa

Working temperature: 220°C-280°C

5, motor

Main motor: Y315L1-6, N=110kw, n=980 rpm

Hydraulic motor: Y100L2-4,N=3kw,n=1480 rev/min

Reducer lubrication motor power: Y90L-4,N=1.5kw,n=1480 rev/min

6, reducer

Space two-flow dedicated hardened gear reducer, HFX900, with its own lubrication system

7, fluid coupling: TVA650

8, hydraulic system (one machine one station)

Hydraulic cylinder: Φ100/Φ56, S=630

9, equipment shape: 6500*2450*3110 (length * width * height)

Third, the key equipment technology

1. Instead of using the traditional "side-by-side tangential inconstant speed" configuration, two side-by-side agitator knives with Z-shaped cross-sections are configured using a "parallel side-by-side overlap and equal velocity" approach. Both of the two agitator blades have the same diameter and are greater than the center distance of the two agitator blades. The agitator blade has a middle radius of intersecting state and rotates at a synchronous rotational speed and is installed at a mutual angle of 90 degrees. The Z-type agitating blade is made of special wear-resistant steel, which greatly improves the service life of the agitating knife. The cutter shaft is made of high-quality carbon structural steel. The cross-section of the cutter body is designed as an oval structure, which effectively prevents the sticking phenomenon of the agitating knife. The cross-sectional area of ​​the cutter body is rectangular, trapezoidal and ovum. In contrast, the oval-shaped cross-section has no sticky material phenomenon, overcomes the granular destruction, and at the same time improves the kneading effect and reduces the wear of the liner and the cutter body itself. In the kneading process of the paste in this case, in addition to the compound movement along the radial and axial directions of the agitating blade, the mutual exchange between the pastes within the range of the agitating blades is accelerated, and the rubbing is strengthened, that is, Pinch this process to improve the physical properties of the paste, while effectively slowing down the wear of the circular arc liner at the bottom of the pot, avoiding mixing pinch dead ends.

2. In the transmission system, a special hardened gear reducer with dual-shaft output and space two-shunt transmission is adopted. It combines the past synchronous gearbox and standard hard-tooth hard retarder and two as one, eliminating the need for a primary transmission. , Lowered the working height of the motor, increased the transmission stability, improved the motor working environment, convenient maintenance and installation, while reducing the equipment footprint and overall weight, so that the matching is more reasonable, the output of the motor and double output shaft force spread The coupling of the dedicated hardened gear reducer adopts a fluid coupling, and the connection between the special hardened reducer and the mixing cutter shaft adopts a gear coupling. This improves the motor starting performance and smooth operation, and improves the drive. Accuracy, reduced energy consumption.

3. The shaft of the mixing cutter shaft is sealed with the outside world. The packing is used to seal the double labyrinth seal. An oil filling device is added to ensure the sealing performance and prevent leakage. Anti-wear measures are adopted. Shaft sleeves are designed at the shaft and seal. The surface is specially treated. The labyrinth is pressed tightly with a special butterfly spring fastening method, which effectively prevents the leakage of the paste and the abrasion of the milling cutter shaft. In the assembly position of the bearing bearing, the cooling water device was designed. According to the expansion coefficient, the accurate tolerance was determined to prevent the bearing from being burned out due to overheating. The bearing adopts a self-aligning roller bearing and reduces the transmission resistance. The pot body is designed. Expansion compensation structure.

4. The liner is made of special materials, which not only greatly improves the wear resistance of the liner, but also enables the liner to have good high temperature oxidation resistance and corrosion resistance. The liner is particularly suitable for the wear resistance requirements of the cathode paste on the liner. The main body liner of the pan adopts an easy-to-remove liner structure, which facilitates the replacement of the arc liner at the bottom of the pan that is most likely to be worn.

5. The heating of the pan is the use of a full-area circular S-loop. The heated area is large. The lid and discharge door are also designed to heat the kerosene. The discharge door is connected to the heating system piping with a high-temperature metal hose. And the gate control flow, so as to avoid the past discharge door heating, due to control failure, and the discharge door overheated and burned, the use of inflexible, and even can not be used. The entire heating is divided into six zones, and the distributor controls the flow of each zone through valves to ensure that the temperature of each part of the pot body is uniform. All flanges are sealed with a metal-wound flexible graphite gasket.

6. Paste temperature measurement point is designed at the center of the mixing cutter shaft. It is not influenced by material accumulation. The material temperature is measured directly from the center of the paste. The heat conductive paste is filled between the temperature measuring tube and the thermocouple. The temperature measurement is accurate and can be avoided. The temperature difference between the surface layer and the interior of the paste. Thermocouples use dual thermocouples to meet the overall automation requirements.

7. Two asphalt injection holes and two dust-discharging holes are arranged symmetrically along the axial direction in the roof of the pot body. There are dispersion plates in the asphalt holes. During the asphalt injection process, the kneading resistance is uniform, which is beneficial to the smooth operation of the whole machine; Increase insulation layer and increase thermal efficiency.

8. The double outer insulation layer effectively prevents the heat from scattering, reduces the energy consumption, improves the kneading efficiency, and improves the on-site operating environment.

9. The electronic control system adopts PLC to compile the controller, and the control level is obviously improved. Besides monitoring the kneading temperature of the materials, the temperature of the heating system can also be monitored, and the unloading process is chained to ensure the loading and unloading of materials. The operation is accurate and can be designed at any time according to the circumstances of the work program, a high degree of automation.

10. Hydraulic interlocking is adopted in the hydraulic design. When the discharge door is not lowered, the discharge door cannot be turned over. At the same time, the chain is also used on the electrical control circuit to form double protection, that is, the swing motor does not work and the thrust cylinder Not working. Increase the centralized lubrication device, perform lubrication lubrication on the mixing shaft and labyrinth seal, bearing parts, and the bottom opening mechanism to reduce the labor intensity.

Fourth, the working principle

HND-4000L hot kerosene heating kneader working principle: the material into the pot through the feeding mouth in the heated pot body kneading heating to a certain temperature, add asphalt, and after a period of kneading, heating to the required temperature after passing through the bottom of the pot Open the door and paste the paste evenly. The bottom door adopts an inverted structure. When the material is unloaded, the swing motor of the two bearings of the bottom door rotates, and the rotation of the lift screw causes the bottom bearing to lower the two bearing seats by 2.5-3mm, so that the bottom door has a certain gap with the door frame of the pot body, and then the thrust force. The fuel tank pushes the discharge door to rotate and rotates 90-110 degrees. After the unloading is completed, the hydraulic cylinder pushes the discharge door back to its original position, and then the swing motor is started. The bottom open door is moved upwards by 2.5-3mm, and the door is tightly closed to complete opening and closing. Close the process. The working process is controlled by PLC programmable controller for automated operation.

Fifth, equipment control

Each kneading pot consists of a centralized control cabinet and a local dust control cabinet (dust-proof grade IP54). This control system adopts S7-200 and CPU224 high-performance programmable controller modules from Germany's Siemens Company. Each of the mixers sets up independent modules to reduce the number of boilers that can be stopped due to PLC damage. Through programming, the process of heating, kneading, feeding, and discharging of the kneader can be automatically controlled. It can communicate with other PLCs through the communication port on the module. The local cabinet can facilitate on-site commissioning and manual operation after the PLC is cut off.

1, the main technical parameters

(1) Main loop

The main motor power 110KW, rated voltage AC380V frequency 50HZ.

Hydraulic motor power 3KW rated voltage AC380V frequency 50HZ.

Reducer lubrication motor 1.5 KW rated voltage AC380V frequency 50HZ.

(2) Control loop

Using isolation transformer AC380/220V frequency 50HZ, power 1KVA, supply PLC power. With DC stabilized power supply to manually operate DC24V DC safe voltage power 1KVA.

(3) Instrument unit

The temperature meter is a DY2000 series smart meter with a cold junction compensation function. The thermocouple thermometric index number is E. Use the compensation wire with indexing number E to connect.

2, the circuit works

(1) Main circuit: The main circuit has three motors, the main circuit rated voltage AC380V, the main motor rated power 110KW, hydraulic motor power 3KW, reducer lubrication motor 1.5KW. Motor protection uses air circuit breakers for short circuit protection, and contactors and thermal relays are used in conjunction with the motor to perform phase failure and overload protection. Each motor has two sets of manual automatic control lines. The operation status and fault conditions of the motor are indicated by the corresponding indicators and the buzzer alarm of the oil fault. The load of the main motor can be set in the centralized control cabinet and local control. The ammeter on the panel detects and indicates.

(2) Control circuit: The control circuit consists of power supply, PLC automatic control and manual control.

a, the power supply part is mainly composed of 1KVA isolation transformer AC380/220V and 1KVA DC power supply AC220V/DC24V. The power supply of the control system is externally introduced into the AC380V power supply, and is supplied to the 380V/220V-1KVA isolation transformer via the circuit breaker F1. The AC220V power supply of the transformer secondary is controlled by the main contacts of the system start contactor KM0 via the fuses RD01, RD02. The power supply of each part of the system, DC24V DC power supply is induced by the secondary of the isolation transformer, and the F4 air circuit breaker enters the DC stabilized power supply module, which is obtained by rectification, filtering and regulation. After F5, DC24V DC power supply is provided to the manual control, which leads from the secondary of the isolation transformer and provides AC220V power to the PLC via F7. Power is supplied to the contactor and solenoid valve via F6. At the same time power the temperature control instrument.

b. On the local control cabinet of the kneader, there is a 1SA mixing pinch control hand automatic conversion button and 2SA hydraulic hand automatic conversion button can facilitate the manual control and automatic control conversion. Prior to the system work, the material control instrument XMT1 quadrant alarm point is set according to the process conditions of the unit. (The temperature setting is for reference only) Both 01 is set as the upper limit of the pot temperature, 02 is set as the upper limit of the dry material temperature, and 03 is set as the material temperature In the upper limit, the lower limit of the temperature of the heat medium oil is detected in the heat medium oil distributor by the thermocouple temperature measurement point, and the heat medium oil control instrument 02 is set to the lower limit of the temperature of the heat medium oil. Rotate 1SA, 2SA to the automatic position and the kneading system will be in automatic control. According to the preprogrammed PLC program, the kneader will automatically complete the kneading process. Firstly, when the temperature of the pot body reached the set value by the thermocouple mounted on the kneading shaft of the kneader, the kneading system sends a signal to the batching system for dry material, and when the batching system finishes discharging, the kneading system discharges the signal and kneads the kneading system. After the machine starts stirring and the dry-mixing timing reaches the time and the temperature reaches the process requirements, the mixing and kneading system PLC sends a permitting asphalt signal to the batching system. After the batching system finishes putting the asphalt, it sends out the asphalt completion signal. When the kneader starts to wet-knead and reaches the time after the time has passed, and the paste temperature reaches the process requirement, the kneading system gives a material to apply for the discharge signal, and when the material feeding car arrives, a signal is given to the PLC, and the PLC receives the signal after the car arrives. Hydraulic system signal, the hydraulic system automatically starts and then opens the door solenoid valve signal discharge door open, when the discharge is completed, the discharge door closes, this completes a kneading process, if there is a failure, press the system stop button or emergency stop button Handle the fault and complete the process manually (see Figure 6).

c. Manual control: Manually control the kneader by turning the 1SA and 2SA to the manual control position. Observe that when the temperature of the local temperature control table of the kneader reaches the required value, press the dry material signal button to request unloading. Press the main motor forward button and start kneading the kneading machine when the dry material is finished ringing. Press and knead for a certain time. Allow the asphalt button to add asphalt. When you see that the buzzer signal is put on the bitumen and knead for a certain time, observe that the temperature of the temperature control instrument reaches the required temperature of the process, press the button to apply for the discharge of the material, and when the ringing bell of the discharge car arrives, rotate the 3SA to the bottom door. Open position. Rotate 4SA to the bottom door open position to discharge. After the discharge is completed, turn the 4SA to the closed position to close the bottom door and rotate the 3SA to the bottom door to the top position. Tighten the pan door and complete a manual kneading process. The above working process can adjust the temperature mastering time according to the process conditions of the unit.

Sixth, in 2006 since the current equipment in the use of carbon plant performance table

Fuping Huaxin Carbon Co., Ltd. HND-4000L 8 Thermal oil 2006.12

Texas Yongxing Heavy Industry Carbon Co., Ltd. HND---4000L 8 Thermal oil 2007.4

Henan Yuhui Carbon Company HND---4000L 2 Thermal oil 2007.5

Fuyang City Carbon Corporation HND---4000L 3 Thermal oil 2007.6

Pingdingshan Sanjiu Carbon Co., Ltd. HND---4000L 1 Thermal oil 2007.6

Lushan Yuanhong Carbon Co., Ltd. HND---4000L 2 Thermal oil 2007.8

Henan Jinhao Industrial Co., Ltd. Carbon Factory HND---4000L 1 Thermal oil 2007.9

Liyang Huanghe Carbon Co., Ltd. HND---4000L 4 Thermal oil 2007.9

Luoyang Jinlong Tianling Carbon Co., Ltd. HND---4000L 8 Thermal oil 2007.11

Zhengzhou City, Sasin Yu Chen Fluor Aluminium Co., Ltd. HND---4000L 6 Thermal oil 2008.1

Linyi Sutong Carbon Co., Ltd. HND---4000L 8 Thermal oil 2008.2

Jiaozuo Bo Love Hengyu Carbon Corporation HND-4000L 6 Thermal oil 2009.1