印尼棉兰2×200MW机组工程气力除灰输送系统设备操作手册总文本.doc

广广东东火火电电工工程程总总公公司司 印印尼尼棉棉兰兰2200MW机机组组工工程程 气气力力除除灰灰输输送送系系统统设设备备 GUANG DONG POWER ENGINEERING CO. PLTU 2 SUMATERA UTARA 2200MW MEDAN FLY ASH HANDLING SYSTEM 操作维护手册 Operation and when boiler being in high load operation, shorten the circle interval time to meet the requirement of the great quantity conveying. 4)Ash conveying system operation method when boiler being shutdown： After the boiler and ESP halts, the ESP rapping system should keep operating more than 3 hours. Then the ash temperature starts to fall, its necessary to decrease the pump ash containing and keep the ash conveying system running continuously, until ensure that the hopper is cleaned up, then open the ESP man-hole for checking. a) System operation to remove blockage It is necessary to remove blockage when pipe blockage occurs in the conveying as follows: Blockage removing method： A: Stop “run”, start “blow” on the CRT operation menu. When the pipe pressure is high, shut off the air manual valve on the pipeline, open the manual blockage relief valve，discharge ash into the ash hopper by the blockage relief pipe. And carry on “pressuredshut off the air valve after pressure increasingopen the blockage relief valve shut off the blockage relief valve after pressure starting to fall”，stop the operation until the highest pressure reaches the blowing pressure, then purging system twice finally. B: If the blockage can not be handled with method A, open the manual vent valve of master pump (or other pumps) at higher pressure, with this method, take out the ash from the pipe to the pump. Need to closely observe the conveying system condition during the ash conveying. The regular system walk-down will be required while keep monitoring the CRT. Spot walk-down Content： 1.Review the temperature on the adaptors above inlet dome valve of vessels. Normally, for the first field , the joint temperature is 90100，for the second field temperature , that is 5070，and for the third to the fifth field ,that is 3050. Review the temperature of this point to check the status of ash falling and ash accumulating in ash hopper. If the joints temperature in the same field has great difference, it is possible that the ash falling will be uneven or bad ash falling occurs in some hoppers. It is necessary to adjust the load distribution of the flue and ESP, adjust hopper aeration gas quantity and ash feeding time, adjust the circle interval time, make the ash falling normal and ensure good operation circle. Review all the joint temperature after a period (about a week) of each operation starting. 2.Ash Falling During the period of the “falling conveying conveying over”, know the ash falling and conveying status by knocking the pump body, or check the ash thickness by opening the manual vent valve. This job must be carried out to know the basic ash conveying status especially at the beginning of the conveying and the pump being still not full. 3.Vent-Pipe And Blockage Relief Pipe Status Setting vent-pipe and valves in the MD pump, the vent valve is opened to exhaust when the MD pump inlet dome valve is opened for ash falling by gravity. At the normal condition, it takes 1020 seconds to full the pump, and the ash falling pipe temperature increases and vent-pipe works normally. If there is enough ash in the ESP hopper, but it is still hard to fill the pump, maybe the vent-pipe acts abnormally without enough venting. Here, the following methods can be used: A：Knock the vent-pipe before opening the vent valve; after turning off the vent valve, stop knocking, and repeat the above to remove handicap. B：Clear the accumulated ash in the pipe through the vent-pipe plug. C：Seal the outlet pipe and shut off the isolated valve above the inlet valve, pressurize the pump and pipeline to 12bar, open the vent valve after knocking pipe. And repeat the above. When the blockage removing goes along well in the blockage relief pipe, obvious sound of material flowing can be heard with the temperature rising. 4.The Working Status of the Pump Fluidizing Air Pipe When ash conveying, the pump fluidizing air valve is open, the air flow sound in the fluidizing air pipe can be heard with the libration. The greater gas dosage is, the greater quiver is; the smaller gas dosage is, the lighter quiver is. If there being no the sound and vibration, it is possible that blockage occurs in the plate and isolated valve caused by impurity. It is necessary to clear the orifice plate and isolated valve and blow the pipe. 5.Conveying Air Avoid more water content in the conveying air. In the dry day, make drainage in air receiver once 2hours, in the wet day, increase the drainage times. 2 Fault Diagnosis And Managing Methods Of Ash Conveying System Warning: Prior to system fault diagnosis, check air & electrical supplies and carry out the protection. When carrying out fault diagnosis, the switch on the CRT menu is set to “stop” or “purge”. symptomPossible causeRemedial measure 1.Incorrect switch position “remote/local-In the “local” position Put the switch of control panel is set to “remote” position 2low conveying main pipe pressure Initiate other compressors, open the valve and check the pressure gauge, pressure switch and pressure transmitter of the air receiver 3.Incorrect dome valve seal pressure signal，control gas malfunction Check all the dome valve status comparing with the dome valve initial status list. If the difference occurs, check the control gas and pneumatic panel gas inlet valve, check and adjust the wrong signal feedback conditions. 4Incorrect path-high level probe alarm of silo Select the correct path. Once the high level probe alarm occurs, the ash silo can not convey. 5Incorrect pipe conveying pressure switch signal feedback Readjust the pressure switch and check the connection 1：circle not starting 6No pressing the CRT menu circulate key Stop other orders and press the operation key 1.Incorrect dome valve seal pressure signal or limit switch fails to work. Check and adjust the wrong seal pressure single feedback accompanying conditions. according to the maintenance manual, exchange the limit switch if failure occurs. 2.Dome valve not closed completely, and the dome or shaft are blocked. Isolate electrically and pneumatically, remove the pipe from bottom bend, clear vessel. Remove the actuator and operate manually, check the limit switch operation 3.Blowing valve not working Under the condition of normal controlling air: Turn on local solenoid, if the blowing valve acts normally, check or change the solenoid, if the blowing valve can not work, repair and change the blowing valve. 2： pump start- up, accomplish ash falling , dome valve is closed, no ash conveying 4.The manual valve of conveying pipeline shut off Open the manual valve 1.Pipeline is blocked and isnt unobstructed. Manual local blockage relief valve. Check the gas supply and power supply. Affirm all the valve working status. From the farmost point of the pipeline, knock the pipe slightly and ensure the position， isolate the gas supply and power supply, reduce the gas quantity. Remove the pipe where the blockage occurs, investigate the reason and blow the pipe. 2.Arch occurs in the outlet materiel. Check bulk and humidity of the pump outlet material 1.Seal pressure decreases to conveying pressure Check the gas supply pipeline 2.Crazing in the dome valve Replace the seal ,check the clearance between the manual and seal 4：inlet dome valve or vent dome valve leakage (note: some little leakage in the sytem is normal 3.Blockage in the strainer Remove and clear 1.Solenoid is not working full travel. Remove and clear5： air venting continuously through opening/closi ng solenoid 2.dome valve actuator seal leaks Fit new seals Ensure the filter and electric heater plate working condition and ensure the ash in the hopper。 6： Abnormal ash falling 1If the ash quantity than the normal condition, the conveying pressure is much lower than the normal conveying pressur Knock the ash hopper vibrator and rigid joints Adjust aeration gas quantity Check the vent-pipe condition and eliminate fault Increasing exhausting with the vent valve, accelerate ash falling 1.Improper orifice plate setting，too fast material flowing Adjust the orifice plate gas quantity 2.Low conveying load Check the vessel filling time, vent valve and vibrator setting, increase the falling ash quantity in the pump 7： bad abrasion of pipe /bend 3.Improper pipe bend installation Locate the position 1The gas source pressure is lower than the design requirement Check the air receiver local gas source pressure. 2Feedback gas pipeline is obstructed. Check pressure gauge display of the local pneumatic panel. When the pressure is lower than the feedback pressure, transact as the following 3,4,5 items.。 3Limit switch non- connection Check connection of the local limit switch and controlling gas pipeline. 4the adjusting bolt need to adjust Adjust the adjusting bolt length 5Gas pipeline connection malposition Check the connection of seal gas pipeline and gas source pressure 6high pressure gauge setting value Check and adjust the pressure gauge setting value properly 8： incorrect feedback signal of dome valve seal pressure 7Group terminal block connection becoming loosing Check the local pneumatic panel power supply and the connection PLC cabinet 8Switch can not be closed Check if there being something 3. Dome Valve Maintenance Instructions PROCEDURE FOR REMOVAL OF DOME VALVE Inlet Dome Valve 1.Fully close isolating valve and run the Ash Vessel until empty. 2.Shut down and isolate system. 3.Disconnect and mark nylon pneumatic pipework to the cylinder/actuator and limit switch, and water pipework to the top plate/dome (high temperature models only). 4.Remove set screws securing isolating valve to adaptor if fitted to Dome Valve top plate. 5.Remove set screws from Dome Valve bottom flange to vessel. 6.Lower vessel by means of the jacking bolts on the feet of the vessel (25mm). 7.Remove Dome Valve by sliding sideways using lifting equipment if possible. Outlet Dome Valve 1.Fully close isolating valve and run the Ash Vessel until empty. 2.Shut down and isolate system. 3.Disconnect and mark nylon pneumatic pipework to the actuator and limit switch, and water pipework to the top adaptor/dome (high temperature models only). 4.Ensure pipework local to valve is supported and remove bolting from both Dome Valve adaptor flanges. 5.Remove Dome Valve by lowering and sliding sideways using lifting equipment if possible. Exhaust Dome Valve 1.Fully close isolating valve and run the Ash Vessel until empty. 2.Shut down and isolate system. 3.Disconnect and mark nylon pneumatic pipework to the actuator and limit switch, and water pipework to the top adaptor/dome (high temperature models only). 4.Remove bolting from both Dome Valve adaptor flanges, and remove the plate orifice and gasket. 5. Detach the bolt between bottom flange and vessel flange. 6. Remove Dome Valve using lifting equipment if possible. DOME VALVE MAINTENANCE INSTRUCTIONS Replacement/Inspection of Dome Valve Insert Seal 1.Remove set screws from top plate/adaptor, lift out the sealing head assembly consisting of top plate/adaptor, insert seal , insert ring and spigot ring . 2.Note the number and thickness of gaskets under the spigot ring. Combinations of 0.4mm, 0.8mm and 1.5mm thickness gaskets are fitted to achieve the required seal gap (between the seal and the dome). 3.Separate the seal from the insert ring and inspect for wear or damage. Replace immediately if necessary. 4.Rotate the dome by hand to check the condition of the bearings . If the bearings are seized or due for replacement proceed to Removal/Replacement of DomeValve Bearings. 5.When re-assembling the valve ensure that the underside of the top plate/adaptor is free from corrosion. All surfaces should be clean in order to form an air tight seal. 6.Lower the gaskets onto the valve body followed by the spigot ring and insert seal/ring . 7.Lower the top plate/adaptor into position taking care not to trap the seal, and tighten down. REMOVAL/REPLACEMENT OF DOME VALVE BEARINGS Vane Type Actuator Version 1.Remove the sealing head assembly. 2.Rotate the dome until it resets in a position halfway between open and closed. 3.Remove the set screws which attach the actuator mounting to the valve body and withdraw. 4.Remove the grease nipples. 5.Turn the valve through 180. 6.Punch out the two inner spring pins securing the dome to the shafts. 7.Withdraw the shafts and lift out the dome . Note if there are any shims present on the shafts. The shims are occasionally fitted at the factory for centralising the dome and should therefore be refitted on subsequent overhauls. 8.The bearings and seals can now be removed by driving them towards the centre of the valve. 9.All machined surfaces should now be thoroughly cleaned/degreased and inspected. 10. Check for surface irregularities in the dome and shafts and replace if necessary. Also de-burr the edges of the two holes and the leading edge of each drive shaft to prevent damage to the replacement seals/bearings on re-assembly. 11. Carefully fit the replacement seal into the locating ring so that the lip on the seal faces the chamfered leading edge of the locating ring. 12. Press the locating rings squarely into the bore. Offer the leading edge of the bearing up to the bore, align the hole in the bearing to the 1/8“ NPT hole in the body. Press in squarely until the bearing sits approximately 3mm below the face of the bore. Repeat for the other side. 13. Liberally pack the space between the seals and coat the bearings with Shell Malleus JB or equivalent. 14.Re-fit the shim(s) if applicable to the correct side of the valve, slide a new O ring (7) over the shafts up to the boss. 15. Slide the shaft through the bearing until it reaches the first seal in the bore. 16. Hold the dome adjacent to the bores and drive the shafts through the seals and the dome using a plastic/hide mallet. 17. Rotate the shafts until the holes in the shaft and the dome align. Grease the spring pins and drive in. 18. Turn the valve through 180. 19. Fit the grease nipples and the actuator. 20. Re-fit the sealing head assembly. 21. Limit Switch Setting Loosen the lock nut on the striker arm and wind up the set screw. With the dome fully closed wind out the screw until the hexagon head touches the plunger on the limit switch. Turn the screw a further 3.25 turns to depress the plunger. Warning : 1)Before carrying out any Dome Valve Maintenance ensure that the temperature has cooled sufficiently. 2)Before removing top plate and removing bearing isolate cooling water supply. ROUTINE MAINTENANCE Before starting any routine maintenance ensure the system is fully both electrically and pneumatically isolated. The remaining pressure is given off. The cool water is shut off, and the dome is fully cooled. Weekly Have polling and look into the operating condition. Monthly Grease Dome Valve shafts and bearings (hydraulic type grease nipples). Use Shell Malleus JB. Check the filtrate/grease subassembly. Watch the filtrate subassembly condition, and clean it (once a year). use: Shell Tellus 37 degree 37 Moibl DTE Oil.Light degree32 BP HLP32 degree 32 Annually 1. check the dome valve limit Switch. 2. pneumatic panel: check up the silencer, and change it timely. And clean filtrate subassembly if necessary. 3.HM isolate valve : clean the dirty of the daft, and grease the shaft, check the valve work flexible. 4.detach the filtrate core from the air injection assembly ,clean and change it. Check the globe valve . 5.check the level probe connecting condition. Every two year Note: shut off the HM isolate valve, run system to the circle end. Remove the fexible joint . Remove Dome Valve using lifting equipment. 1) Remove Dome Valve and check dome and head for seal wear. 2) Check Dome Valve shafts for wear and replace bearings and seal if necessary. 3) Pneumatic panel: check connecting condition electrically and pneumatically. Dome valve and actuator: check the nick, pitting ,rust of the actuator inn