Saw Steel Pipe,Reciprocating Saw Steel Pipe,Wire Saw Steel Pipe,Band Saw Steel Pipe TIANJIN YOUFA STEEL CO., LTD , https://www.cnyoufasteel.com
MODEL PARAMETERS 1 OVERVIEW Unit 3 of Hohhot Thermal Power Plant is a steam turbine with CZK / 300 / 350-24.2 / 566/566 / 0.4 type supercharger manufactured by Harbin Co., Ltd. Critical, intermediate reheating, single-shaft, twin-cylinder double-row steam, direct air-cooled, heating and heat extraction steam turbine generator set. High and medium pressure cylinder inlet valve with floor-standing on both sides of the two fixed-pressure high-pressure main steam regulating valve, from each side of the two regulating valve outflow, after four high-pressure steam into the high-pressure cylinder, left and right sides symmetrical Arrangement; steam turbine with valve management approach can be achieved throughout the week into the steam and some into the steam into the two different modes, and to achieve throttling regulation and nozzle adjustment of the interference-free switch; nozzle with steam (part of the steam ), The high-pressure part of a total of four adjustable door, corresponding to the four groups of nozzles, nozzle group and adjust the door number corresponding to face the head left for the I, clockwise for the II, III, IV, # 3 unit For I + II + III + IV. The # 3 steam turbine digital electro-hydraulic control system adopts the XDPS-400 control system of GE Xinhua Control Engineering Co., Ltd. [1]. The hydraulic system adopts the complete set of high-pressure anti-fuel EH device of Harbin Turbine Control Engineering Company. Valve servo drive card with intelligent VPC module (Figure 1), the door regulator valve using the United States Morgan nozzle baffle servo valve [2].
2 Symptom # 3 frequent fluctuations in the normal operation of the GV3 valve, inconsistent command and feedback, and suddenly shut down and other issues, this issue has been plagued by steam turbine and thermal professionals began to judge the servo valve failure or control circuit cable fault However, after repeated inspections by the steam turbine and the thermal engineering professionals, after eliminating the fault of the control loop cable, the special technical measures have been taken to replace the servo valve and the problem persists. Finally, it is determined that there is a fault in the intelligent valve servo module of the GV3.
3 VPC valve actuating line replaceable module technical measures (1) before the valve actuating module replacement tissue operator Trial host disc motor vehicles, AC, DC lubricating oil pump , an oil pump shaft top, ensure proper. (2) Valve servo module replacement process to strengthen the monitoring staff to monitor vibration, such as shaft vibration exceeds the control value should promptly notify the thermal workers to stop working. (3) After the valve servo module is replaced, people should carry the communication equipment in place during the debugging process to observe the movements of the adjusting door and the actuator and find that the jam, vibration or other abnormal phenomena should be promptly informed to the operators and test personnel. (4) The work process of thermal workers to strengthen guardianship to prevent personnel misuse. (5) During the dynamic debugging of # 3 unit GV3, the operator should strengthen the unit load monitoring, make the load fluctuation, and adjust the thermal parameter fluctuation manually. (6) Any abnormalities during commissioning immediately report the value and stop operation. (7) Contact the system manufacturer of XDPS-400 and GE Xinhua Company, and confirm that the system supports online replacement of modules and online replacement precautions.
4 VPC valve servo module online replacement (1) exit # 3 machine "shaft vibration large" and "DEH110% speeding" protection. (2) Cut # 3 unit coordination control system. (3) Cut the # 3 unit DEH into the single-valve control mode, pay attention to monitor the vibration, temperature and displacement during the switching process. (4) Exit from the # 3 unit AGC control, using the heel furnace method. Unit load stability at 220MW or so, keep the thermal system is stable. (5) the thermal signal in the logic of the mandatory closure of the GV3 slowly, GV3 in place to confirm the place, turn off, back to the throttle. (6) Exit # 3 Unit DEH Auto (cut to manual on DEH pallet). (7) The thermal engineer dials out the GV3 servo card, sets the jumper of the new servo module, ensures that the jumper of the new module is the same as the jumper setting on the original servo module, then insert the new module into the chassis, At the same time observe whether there is abnormal alarm DEH system. (8) Run DEH-V valve servo module debugging program, check the new servo module in the module area parameters, the servo module zero setting. (9) The operator will cut DEH from "manual" to "automatic", meanwhile observe the load of the unit and the status of the valve. If it is not normal, immediately switch the DEH to manual to inform the thermal workers to check the process. (10) # 3 Unit DEH is put into automatic normal state and put into power loop. At the same time, operators strengthen the monitoring of # 3 unit vibration, bearing temperature and high-profile door opening degree and strengthen the adjustment of important parameters such as main steam pressure and steam temperature.
5 VPC valve servo module online debugging (1) # 3 unit load stability at 220MW, DEH single valve control, the power circuit into normal; if the high-profile door opening 6 Conclusion With # 3 unit DEH cut for the sequence valve, GV3 high profile The state of the door is stable. The online replacement of the GV3 valve servo module is completed. The commissioning is completed successfully. The unit runs stably and the parameters are normal and reliable in the whole process, ensuring the safe and stable operation of the unit.
References [1] People's Republic of China Power Industry Standard. DL / T774-2004. Thermal power plant thermal automation system maintenance operation and maintenance procedures [S].
[2] Shanxi Electric Power Industry Bureau. Turbine equipment operation [M]. Beijing: China Electric Power Press, 1997: 66-68.
[3] Shanghai Xinhua Control Engineering Co., Ltd. XDPS Hardware Manual [Z].
Abstract: Aiming at the anomalies such as swinging, sudden closing of high-pressure regulating door and inconsistent command and feedback during the operation of the unit, measures were taken to eliminate the faults of the control system lines and channels and servo valves . After investigation confirmed the valve servo module failure, the development of technical measures online replacement valve servo module, and successfully debug high-profile door.