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This post was last edited by qy576100527 on 2017-6-1 23:01. System Startup (III) – Individual Testing of the Syngas Compressor. I. Conditions and preparatory work for testing: 1. The turbine and its auxiliary equipment have been installed; electrical and instrumentation systems have been inspected and found to be in good condition. The installation site is clean, with all materials removed and the area tidy. 2. Oil cleaning is satisfactory, and the cooling water system has been established and is operating properly. 3. The steam system is functioning properly, and the condensate system is also in good working order. 4. Mechanical, electrical, and instrumentation teams on standby at the site. 5. The oil system circulation is established properly; the oil pressure is adjusted to normal levels, and the main and auxiliary oil pumps operate normally during testing. 6. Confirm that the couplings between the turbine and the compressor are disconnected, that all interlocks and alarms have been disabled, and that the static testing of the control system has been successful. 7. The vacuum condensation system and shaft seal system are operating normally. II. Pipe warming 1. Verify that the temperature and pressure of the medium-pressure steam are normal, and inform the dispatch team to prepare for pipe warming. 2. Start the turbine barring device to turn the turbine. 3. Open the drain valves located before the high-pressure steam shut-off valve to drain water from the pipeline ahead of the main steam valve; after opening the main steam shut-off valve, open the various drain valves, as well as the cylinder drain valve and the pipe warming vent valve. 4. Slightly open the bypass valve of the main steam isolation valve and set the control pressure at 0.3 MPa, to warm up the pipeline between the high-pressure steam valve and the main steam valve. 5. After the drain pipe has expelled all the dry steam, slowly open the bypass valve. 6. When the wall temperature of the steam pipe reaches the saturation temperature of low-pressure steam, which is 147°C, the pressure can be increased to warm the pipe. 7. Gradually open the bypass valve to increase the steam pressure, controlling the heating rate of the pipeline at 5–10°C/minute, until the bypass valve of the high-pressure steam main is fully open. 8. After the high-pressure steam bypass valve is fully opened, slowly open the high-pressure steam stop valve and close the bypass valve. 9. During the pipe warming process, the turning gear should be started to ensure even heating of the rotor; attention should also be paid to improving drainage to avoid water hammer. 10. The pipe is considered qualified when the temperature of the high-pressure steam exceeds its corresponding design pressure and saturation temperature by 50°C. III. Single-unit trial run 1. Remove the coupling between the turbine and the compressor to disconnect them, thereby creating the conditions for a single-unit trial run. 2. Notify the control room and dispatching team to prepare the turbine for a single-unit test run. 3. On-site, lift the handle of the emergency trip solenoid valve to raise the filling rod of the tripping valve cylinder, thereby supplying oil to the cylinder of the main tripping steam valve. 4. Press the start button in the central control panel, and check the control screen in the control room to ensure that all conditions are met for starting up. 5. Slowly turn the start handle clockwise on-site to gradually open the main steam valve for tripping, and spin up the turbine to around 500 rpm; run it for about 45 minutes to warm it up at low speed. 6. During the warm-up period, it is necessary to thoroughly check for any abnormal noises inside the cylinders, as well as the shaft vibration and shaft displacement of the turbine, the oil pressure and temperature of each bearing and the condition of the return oil flow. Additionally, the exhaust pressure and temperature of the turbine, as well as the thermal expansion of the cylinders, should be checked. 7. Record the shaft vibration, shaft displacement, temperature, and other conditions at each rotational speed. 8. After steam is introduced into the turbine, it is necessary to verify whether the rotor is rotating; if it does not rotate, the main steam valve should be closed immediately to investigate the cause. 9. Once it is confirmed that there are no issues with the turbine, increase its speed according to the speed-up curve. Maintain a speed of 1000 rpm for 20 minutes, and maintain a speed of 3000 rpm for 10 minutes before checking to see if everything is normal. Increase the speed rapidly and smoothly; make sure not to pause at the critical speed of 5700 rpm – quickly pass through this point. Once the speed reaches 7000 rpm, maintain it for 10 minutes before increasing it further to the lowest speed set by the governor. 10. Once the governor reaches its minimum operating speed, and after observing the control valve begin to close, slowly open the emergency shutdown valve by turning the handwheel back one full turn. 11. When the turbine speed reaches the minimum control speed, the governor begins to control the speed by closing all drain valves on the turbine casing and pipelines. IV. Turbine overspeed trip test 1. When the turbine reaches the lowest operating speed set by the governor, check the vibration of each shaft, shaft displacement, oil temperature, and other parameters, and make records of them. Once everything is normal, the control room operator uses the speed-up button on the control panel to gradually increase the turbine’s speed to a maximum of 12,337 rpm. It is then necessary to verify that the vibration, displacement, oil temperature, pressure, and other parameters of the turbine are all within normal ranges, and again, records should be kept. 2. After all indicators meet the requirements, manually shut down the machine (press the emergency stop button) to check whether the turbine can stop automatically, and make proper records. 3. Restart the turbine and increase its speed in accordance with the speed-up curve until it reaches the lowest setting of the governor. Operate the unit at this speed for a period of time (about 10 minutes) to conduct a thorough inspection. 4. The control room uses the speed-up button on the control panel to gradually increase the speed of the turbine via the governor. When the turbine’s speed reaches the set tripping speed of 13,571 rpm, it is observed whether the turbine trips, and the tripping speed is recorded. The overspeed tripping test is repeated, and the recorded tripping speed is compared with the set value; a difference of ≤2% between each tripping speed and the set value is considered acceptable, otherwise adjustments are made. V. Inspection of the governor’s control system 1. During the overspeed test, use the governor to raise the speed to its maximum value, and then reduce it to the minimum value. 2. During the acceleration and deceleration process, check the difference between the actual speed and the reference speed and make adjustments accordingly. VI. Precautions after shutdown 1. Control the deceleration and shutdown according to the operating curve, and record the time. 2. Immediately break the vacuum after shutdown, reduce the vacuum to 0, and shut down the shaft seal system. 3. Ensure that the condensate system and the oil system operate separately for 12 hours and 48 hours respectively. 4. Immediately open the drainage and condensate drains. 5. Start the barring system to turn the turbine.