Vacuum pump maintenance records with pictures and texts

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Equipment maintenance record Equipment name Removing phenol tower Vacuum system number ------------------ Type Roots vacuum pump Maintenance date ------------------ Maintenance personnel --------------------------------------------------------------- Equipment failure The vibration on the non-driving side increased, about 11mm/s, which was increased from the previous 5.0mm/s. Handle the situation of disassembly and overhaul. Accessories consumption status driver end: Double row radial deep groove ball bearing #3211 (2 pieces) ； Outer ring single rib single row radial cylindrical roller bearing, #NF210, (1 piece) ； 2 PTFE retaining rings ； Oil seal 65-90-10, 2 pieces ； Oil seal 50-72-12, 1 piece ； A set of machine seals, RS50 ； Gasket. Non-driving end: 2 PTFE retaining rings ； Oil seal 65-90-10, 4 pieces ； Outer ring single rib single row radial cylindrical roller bearing, #NF211, 2 pieces ； Oil seal 50-72-12, 4 pieces ； 2 sets of single spring mechanical seals, T2 1 7/8“ ； Oil seal 45-68-12, 2 pieces ； other: 2 types of interstage split seal rings, 6 large ones and 2 small ones ； Several gaskets ； Bearing positioning sleeve. Adjust some shims ； 2 boxes of sealant. Cause Analysis 1. Bearing wear causes increased vibration ； After disassembly and inspection, it was found that the non-drive end bearing rollers were slightly worn. ； 2. Foreign matter is stuck to the rotor, causing poor dynamic balance of the rotor and increased vibration. ； Disassembly and inspection revealed that there were many white foreign objects stuck to the surface of the rotor, presumably BPA powder. Note 1. The sealing gasket must be selected correctly to prevent cooling water leakage. ； 2. When adjusting the axial deflection of the gasket, the compression allowance of the gasket must be considered when installing. 3. The position of the positioning sleeve of the driving ring of the drive end machine seal needs to be measured when disassembling and assembling. Remember the position to facilitate adjusting the compression amount of the machine seal when reassembly. ； 4. When installing the single-spring machine seal at the non-drive end, the sealing rubber ring in the moving ring cannot be flanged, and the positioning circlip must be stuck in the positioning groove. ； 5. When the vacuum pump is reassembled in sections, it must be confirmed that the positioning pins between sections are installed in place. 6. Before disassembling the synchronization gear, clearly mark the relative position between the rotor shaft and the shaft, the relative position of the gear and the gear, and the relative position of the gear and the shaft. You can stamp it with a steel stamp to facilitate reassembly. 7. For vacuum pump B, the secondary clearance needs to be appropriately enlarged, (s2+w2, s6+w6), especially the secondary clearance of the driven shaft rotor is relatively thick. When adding a gasket to the positioning bearing to adjust the axial clearance, it is necessary to consider making the driven side positioning bearing gasket thinner than the active side gasket. (Active side gasket 0.45mm, driven side gasket 0.36mm) Maintenance process 1. Understand the fault situation of the vacuum pump, confirm the specific maintenance items, and prepare necessary drawings and materials ； Prepare maintenance tools, measuring tools, lifting equipment, accessories and materials ； 1. According to the process production arrangement, the operator will power off the equipment, drain it, and stop the cooling water. ； 2. After confirming that the process treatment meets the safety maintenance conditions, remove the insulation, and the instrument personnel will remove the relevant instrument lines. ； Disconnect the inlet and outlet flanges and add blind plates to the pipe openings ； 3. Disassemble the vacuum pump as a whole on site. 4.1 Remove the belt safety cover and remove the belt. ； 4.2 Disconnect all accessory cooling water lines ； Remove anchor bolts ； 4.3 Hang the inverted chain on the upper beam, and the lifting personnel will cooperate to lift the vacuum pump down as a whole. ； 4.4 Forklift cooperates to transport the pump to the maintenance site for disassembly and overhaul ； 5. Disassembly and overhaul (to ensure easy disassembly and assembly, place the pump driving end vertically downward on the maintenance platform bracket) 5.1 Before disassembly, open the observation hole, use a feeler gauge to re-measure the gaps between the rotors and end plates at each level and the gaps between the rotors, and make records, as shown in the table below: Unit 0.01mm Active side from the east side S1W1S2W2S3W3S4W4S5W5S6W6S7W7S8W8 23252035332735452517203232253338 5.2 Mark the connection parts of each component of the vacuum pump and mark the order to facilitate reassembly. ； file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A3D.tmp.jpg 5.3 Remove the pulley on the driving end of the vacuum pump ； 5.4 Remove the static ring base of the driving end machine seal. Pay attention to the gasket behind the static ring base (there is no gap on the edge of the inner diameter). Remove the seal chamber with the cooling water jacket. Pay attention to the gasket on the back side of the seal chamber with a gap, which is the location of the oil return tank. ； Before disassembling the machine seal moving ring and the moving ring positioning sleeve, it is necessary to measure the position of the moving ring positioning sleeve. ； Remove the bearing seat (1) ； Remove the fuel tank ； Remove the synchronization gear (note that the gear meshing positions are marked relative to each other) ； Remove the bearing gland, disassemble the bearing seat (2), and use a micrometer to measure the thickness of the adjustment gasket behind the bearing seat as a reference for reassembly, 0.35mm. 5.5 Put rubber on the support of the inspection platform, use an inverted chain to place the vacuum pump vertically, with the drive end on the lower side ； 5.6 Disassemble the water tank at the non-driving end of the vacuum pump. Remove the sealing gasket between the water tank and the oil tank as completely as possible to facilitate comparison with spare parts. ； Check the water tank shell, no damage or cracks ； 5.7 Disassemble the machine seal circlip, remove the moving ring, and disassemble the static ring seat. Try to ensure the integrity of the moving and static rings of the machine seal. Check the end faces of the moving and static rings of the machine seal to see if there is any serious wear. ； 5.8 Disassemble the fuel tank. Remove the gasket between the fuel tank and the side frame as completely as possible to facilitate comparison with spare parts. Check the fuel tank shell for no damage or cracks. ； 5.9 Disassemble the bearing spare mother, the bearing gland, the bearing seat, take out the bearing inner ring and rollers, check that there are signs of wear on the surface of the rollers, and remove the PTFE retaining ring. ； file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A3E.tmp.jpg 5.7 Loosen the 8 long bolts, remove the non-drive end side frame, the adjustment pad between the side frame and the partition, measure the thickness with a micrometer, and record it. ； 5.8 Disassemble the shells and partitions of the rotors at each stage in order, and use a micrometer to measure the thickness of the gaskets between each stage and record them. ； Check the surface of the rotor. There are many white foreign objects stuck on it, as shown in the picture below.: file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A3F.tmp.jpg 5.9 The disassembly of the vacuum pump is completed. 6. Part replacement and repair 6.1 Replace all bearings and oil seals ； All open sealing rings between the rotor stages are replaced ； Replace all sealing gaskets and adjusting gaskets ； Mechanical seal replacement ； The surface of the rotor and the end surface of the partition are polished with fine sandpaper. ； Clean and remove rust from fuel and water tanks ； file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A50.tmp.jpgfile:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A51.tmp.jpg 7. Pre-assembly 7.1 According to the previously recorded thickness of the gasket between the partition and the end face of the rotor cavity at each level, and the theoretical calculation value, add new gaskets and reassemble step by step. After each level of reassembly is completed, tighten the nuts of the 8 screws and use a feeler gauge to measure the total gap from the rotor end to the partition end. Compare with the standard data and calibrate step by step until all four levels are pre-assembled and re-measure the total gap. ； file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A61.tmp.jpgfile:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A62.tmp.jpgfile:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A73.tmp.jpg 8. Assembly 8.1 Replace all open sealing rings between the rotor stages. ； 8.2 According to the determined gasket thickness between each level, install appropriate gaskets between each level and apply an appropriate amount of sealant. After each level is reassembled, tighten the nuts of the 8 long bolts and re-measure the total gap from the rotor end face to the partition end face with a feeler gauge. Compare with the standard data and calibrate step by step until all four levels are assembled and re-measure the total gap. ； 8.3 If the total gap is within the standard range, the following reassembly can be performed ； 8.3 Reinstall the PTFE retaining ring at the non-drive end ； 8.4 Reinstall the bearing seat and bearing, use the spare nut to tighten the bearing, and lock it with the locking plate ； 8.5 Use an inverted chain to place the vacuum pump horizontally, and reinstall the PTFE retaining ring at the drive end. Based on the measured total clearance of each stage and the standard clearance value of each stage, refer to the data measured before disassembly, determine the thickness of the adjustment gasket behind the bearing seat, and reinstall the bearing seat and bearings. ； 8.6 Preparing the gear of the driven shaft ； Use machined bushings and spare mothers to tighten the gears of the driving shaft ； 8.7 Use a feeler gauge to measure the clearances between the rotor end faces of each stage and the partition plate end faces, and compare them with the standard data. If they are within the range, the following installation can be performed (if there are data that are not within the range, the overall clearance value needs to be considered, and the thickness of the gasket behind the bearing seat should be adjusted evenly. )8.8 Adjust the gap between the rotors. Reinstall the driving gear and tighten it with the lock nut. Reinstall the driven gear without tightening it. ； 8.9 Determine the range of the gap between the rotors, pick a maximum value, use a feeler gauge with the same thickness as the gap, and insert it into the specified position (the rotor is placed vertically and horizontally) ； 8.10 Tighten the gear, re-measure the clearance, turn the gear, and measure the clearance at the same point at different contact positions to ensure that it is within the standard range. 8.11 Reinstall other components in order, paying attention to the shape of the sealing gasket being consistent with the original gasket. 9. On-site overall reassembly. 10. Single machine test run, vibration and temperature are normal. 11. Please see the following table for maintenance quality standards.: Gap data measurement file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A84.tmp.png1.真空泵驱动端在下，垂直安装时的数据：按照资料分析，若垂直安装，S1，S2，S3的数据是0mm。 ——When the bearing is not installed. 2. Pre-installation data - theoretical maximum value in mm, minimum value, maximum value S1S5W1W5S2S6W2W6S3S7W3W7S4S8W4W8S1S5W1W5S2S6W2W6S3S7W3W7S4S8W4W8 00.4500.4500.450.050.5500.6500.6500.650.050.8 - Actual measured value 0.01mm Active side and driven side S1W1S2W2S3W3S4W4S5W5S6W6S7W7S8W8 056057053570054054052564 3. Data during formal installation - theoretical value mm file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9A94.tmp.jpg ——Actual measured value mm Minimum value Maximum value S1W1S2W2S3W3S4W4S5W5S6W6S7W7S8W8 23332532183525502232223217352544 4. Gap between rotor and rotor, rotor and shell file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9AA5.tmp.jpg file:///C:\Users\ADMINI~1\AppData\Local\Temp\ksohtml\wps9AA6.tmp.jpg ——Actual measured value mm 1234 T1T2RT1T2RT1T2RT1T2R ————0.35————0.35————0.35————0.35