Hebei Metallurgical Society 2013 Air Separation Professional Academic Exchange Conference Air Separation Air Compressor Anti-surge and Interlocking Parking Control System Reconstruction Li Xiaohong Qiu Fachun Pang Zhongjun Wu Xiangjun Zhang Jinzhong Gu Shiping Zhou Yanhong Hebei Xuanhuan Gas Gongs, Hebei Industrial Zone, Xuanhua District, Zhangjiakou City, 14 No. 075100 is equipped with hardware and control procedures to improve the transmission of analog signal cable and transmission logic signal cable to ensure normal operation of the air compressor. The air compressor of our company's 5 air separation system is a three-stage turbo air compressor, which is produced by Atlas Company of Germany and is an axial gear driven by integral gear. Main technical indicators: IU machine 屯 music 6000V, rated current 680A, rated power 7200KW, designed exhaust; E is 80000m3 / h, designed exhaust pressure 0.5Mpa. The whole set of air separation process system uses distributed control system, referred to as DCS, The system consists of an operation management level (Operation Station OS, Engineer Station ES and Gateway) and a process control level (Process Station PS and Field Controller AC800F). Engineer station operation ra station remote monitoring room AdGGFR redundancy 掊 1 / 1 has repeatedly appeared W part of the instrument å¿ measuring point signal false positives caused by air compressor interlock parking or anti-surge valve full open accident, affecting steelmaking produce. The analysis of the interlocking parking and surge principle of the air-checking machine is as follows: 1. Air compressor interlocking parking condition c Motor stator temperature is large T10 (TC; d. Run oil oil temperature j66 °C eJK shrinking machine bearing Temperature is greater than 96 °C; fiVj is low along the oil level "82KPa; gJK shrinking machine high and high temperature surge line eight a line regulator control set value straight line 7~07 = safety margin map i air compressor In the schematic diagram of the surge line and anti-surge line, Pd is the outlet pressure, kPa; Ps is the inlet pressure, kPa; C is constant (determined by the size of the orifice), and m2:h is the differential pressure of the orifice (the relationship with the flow m) The formula is Q2=h), kPa; 2. According to the air compressor anti-surge and interlocking parking control principle, the accidents caused by false alarms at the collection points of the air compressor site are taken, and 5 measures are taken and analyzed in the instrument control. As follows, the false alarm of the air compressor surge accident is caused by the inaccuracy of the air compressor exhaust pressure or the flow value, and the surge controller (which is realized by the configuration) is set according to the controller. Value and exhaust pressure value, flow credit value to calculate the current working point of the air compressor; when the working point fluctuates to the upper left of the surge line, the anti-surge valve solenoid valve Electric, the valve is fully open, the air compressor inlet guide vanes are closed to the S small opening degree. To prevent the accident from happening, the pressure guiding tube of the pressure differential pressure transmitter is added with a buffering bend, and the IL two measuring points are each phase-increasing One transmitter. One pressure value and one flow value are a group. The two sets of values ​​are used to calculate the working point of the air compressor. If the values ​​of the two working points all enter the surge zone and the two yeast values ​​are deviated There are few, depending on the unit surge, otherwise the unit does not surge. (2), air compressor bearing temperature, motor stator temperature, lubricating oil temperature is measured by platinum thermal resistance, W such resistance is easy to occur short, open circuit fault, or resistance change due to external interference, etc., transmission A false temperature signal causes parking. Therefore, the temperature interlocking switch signal is delayed by 3S to avoid parking due to false signals. (3), lubricating oil pressure fluctuations often occur interlocking malfunction, resulting in unnecessary parking. To this end, we add a buffer tank to the oil pressure transmitter pressure regulating tube to reduce oil pressure fluctuations, and add a hydraulic pressure transmitter. In the oil test:! In the R module, the measurement of the two transmitters: S value ~ hydraulic interlocking parking value is compared, when H is too high, the hydraulic interlocking switch signal value is true, and the air compressor interlocks to stop. (4) The simulated scene signal has poor anti-interference ability to the step signal, and avoids the transmission of the cable in the same tube (or tip), otherwise it should be effectively isolated. For example, when the phantom/stop liquid é“– filling bottle pump, the 4-axis displacement signal of the idler shaft vibration has a large step fluctuation and causes parking. By replacing the vibrating heart 'displacement test probe, the phenomenon is not eliminated. æ³ ä¿¡å· å‘现 IU IU IU IU IU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Cards. The liquid helium filling bottle pumping machine control circuit is as shown. The power source iLiH of the control circuit is 220VAC. When the ["/stop liquid test fills the bottle pump, the logic signal cable has a large change in the circumference of the cable. Under the action of changing the field, the 1j axis displacement signal of the air compressor shaft vibration is optimized and improved. Any one of the above measuring points meets the above conditions will cause the air compressor to interlock and stop. Surge is the vibration of an unbalanced condition that occurs when the turbine compressor reduces the flow to a certain extent. The characteristic curve of the compressor can be obtained from the air flow ratio Q and the pressure ratio P as shown. At the upper left of the surge line is the unsteady working area of ​​the air compressor, that is, the surge area, and the lower right part is the stable working area. When the operating point enters the left area of ​​the surge line, the anti-surge valve solenoid valve is de-energized and the anti-surge valve is fully open. Inductive current appeared in the cover of the 2013 Air Separation Professional Academic Exchange Conference of Hebei Metallurgical Society. Through the coupling between the shielding layer and the core wire, a false signal appeared, causing false parking. After that, the control part of the middle dashed line is replaced by two relays in the local control box of the filling bottle. The power supply of the relay coil is provided by the newly added DC24V power supply box, and its power loss and loss are still controlled by the original logic output card. The interference disappears and the fault is eliminated. Manual automatic instrument control start-stop operation stop liquid oxygen filling bottle è¥ electric control diagram (5), the axial displacement is measured by the probe near the end face of the shaft, in the conductive material can generate eddy current, when the probe-ij axis distance When increasing, the generated eddy current is weak, and the absorbed energy is small, so that the signal of the loop is strong and the voltage is high; on the contrary, when the gap distance between the probe and the shaft is the smallest, the eddy current generated is the strongest, and the absorption energy is large, so that As a result, the electrical signal is small and the pressure is low. Because the electrical signal is very weak, the voltage is converted to a turbulent signal by the preamplifier and transmitted to the I/O card. The signal transmission process is easily disturbed, resulting in system instability or even misoperation. Therefore, a source isolator is added to increase the power of the mountain. With this isolation technology, the input, output or source components are not interfered with each other, and the three are also electrically isolated from each other to ensure the authenticity of the signal and avoid parking. 3. Concluding remarks in practice, after the improvement of the air compressor interlock protection, the problem of accidents in the control is solved, and the operation of the equipment is stabilized, so that the DCS is more suitable for the needs of equipment control, operation and accident handling. To lay the foundation for stable production of steelmaking. Flatbed Container Trailer,3 Axle Flatbed Semi Trailers,Flatbed Container Semi Trailer,3 Axles Container Trailer Shandong Chengda Auto Sales Co., Ltd. , https://www.chengdasemitrailer.com