Original driving and purging plan for position change

Purging of process pipelines in the conversion process – Description of the pipeline purging procedure: For the purging of the desulfurization conversion and conversion process pipelines, lines A-22-4″ and A-20-10″ are utilized. 3.4.5.2 Purpose of purging: To remove slag, debris, rust, and sediment remaining in the equipment and pipelines from the desulfurization, conversion, and reforming systems during construction and installation, so as to prevent blockages in the pipelines during operation, damage to valves and instruments, damage to pumps and machinery, and contamination of the catalyst solution. Therefore, a thorough purge must be carried out before driving. 3.4.5.3 Preparations before purging: 1. The equipment, pipelines, and valves of the conversion, desulfurization, and shift systems have been installed and thoroughly inspected. 2. The 101-J unit has passed the testing and is in standby mode. 3. During purging, a purging procedure diagram must be available, and purging must be carried out in accordance with the specified sequence; those involved in the purging process must be familiar with the purging route. 4. To ensure the smooth progress of purging, communication devices must be prepared. 5. Large pipeline equipment should be cleaned manually as much as possible. 6. To ensure the progress and quality of purging, a sufficient number of fitters, plumbers, and electric/welding workers must be available to remove and install blind flanges, as well as to assist with the purging processes during shift changes. 3.4.5.4 Precautions during purging 1. Before purging, the orifice plates and demisters must be removed and kept by a designated person. The valves for pressure gauges, level gauges, and analysis sampling points must be closed tightly. When gas passes through control valves, shut-off valves, and electric valves, the area in front of those valves must be thoroughly purged. 2. Blind plates must be installed at all locations where they are required, prior to purging. 3. Demarcate the area, draw red lines to prevent unauthorized personnel from entering, and install warning signs. No one is allowed to work at the purging ports to avoid injury from any substances that may be expelled. 4. For safety valves larger than 2 inches, the valve must be disassembled for purging; those 2 inches or smaller require the installation of blind flanges. 5. Purge the pipelines, paying attention to analysis points, pressure points, liquid discharge points, etc., as well as the purging of small pipelines. 3.4.5.5 Purging Methods and Standards 1. During purging, it is necessary to proceed in sequence, but the various temporary lines can be purged alternately. Care must be taken when reversing the flow of gas, in order to minimize pressure fluctuations. 2. Equipment that has been purged should be covered with baffles or blind plates; some equipment needs to be returned to its proper position to prevent dirt from entering the next piece of equipment. 3. At the exhaust outlet, use lead-tinted cotton boards to inspect the exhaust gas in order to determine whether the purging is satisfactory. 4. The container-type equipment must be opened, and cleaning should be carried out through the manhole. 3.4.5.8.1 Purge PG-6-18″ and PG-7-12″ pipelines. 1) Remove the inlet flange of 103-C process gas, install a blind plate on the equipment side; remove the inlet flange of 104-C as well, and install a blind plate on the equipment side. 2) Open the stop valve on A-20-10″, and slowly close the stop valve on A-25-4″ to purge the pipeline in “1” until it meets the requirements. 3) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 4) Remove the blind flange at the process gas inlet of 103-C and reset the flange. 3.4.5.8.2 Purging PG-8-18″ pipeline: 1) Open the stop valve on A-20-10″ and slowly close it to full closure; then open the stop valve on A-25-4″ and purge the pipeline mentioned in “2” until it meets the requirements. 2) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 3) Remove the blind flange at the 104-C inlet and close the flange. 3.4.5.8.3 Purge PG-9-18″ and V-5-6″ pipelines: 1) Close the globe valve on V-44-8″, close the globe valve on PG-20-8″, and close the globe valve on N-20-18″. 2) Remove the inlet flange of 104-DB and install a blind flange on the 104-DB side. 3) Open the stop valve on A-20-10″, slowly close the stop valve on A-25-4″, and purge the pipeline in “3” until it meets the requirements. 4) Open the shut-off valve on V-44-8″, and reset it along with the blind flange and the 104-DB inlet flange. 3.4.5.8.4 Purging the N-20-18″ pipeline 1) Move the \"8\"-shaped blind plate on N-20-18″ to the \"open\" position. 2) Remove the flange at the process gas outlet of C66403 and install a blind plate on the equipment side. 3) Close the bypass valve C66403, open the stop valve on N-20-18″, slowly close the stop valve on V-44-8″, and purge the pipeline in “4” until it meets the requirements. 4) Open the shut-off valve on V-44-8″. 3.4.5.8.5 Purge lines N-19-18″ and N-18-18″: 1) Close the process gas outlet flange C66403 together with the blind flange. 2) Remove the outlet flange of J66402 and install a blind plate on the equipment side; remove the process gas inlet flange of C66403 and install a blind plate on the equipment side as well. 3) Open the stop valves on N-19-18″ (two) and N-18-18″, slowly close the stop valve on V-44-8″, and purge the pipeline in “5” until it meets the requirements. 4) Open the stop valve on A-25-4″, close the stop valve on A-20-10″, and close the stop valve on N-20-18″. 3.4.5.8.6 Remove the blind flange at the J66402 outlet, remove the blind flange at the C66403 inlet, and reset the flanges. Remove the blind flange at the 104-DB inlet and reset the flange. 3.4.5.8.7 Disassemble the 104-DB manhole and manually clean the 104-DB thoroughly. Re-seal the 104-DB manhole. 3.4.5.8.8 Purge PG-10-18″, PG-20-8″, PG-10-20″, PG-11A-16″, PG-11B-16″ pipelines. 1) Close the stop valve on N-15-18″. 2) Disconnect the inlet flange for the 105-CA/CB process gas, and install a blind plate on the equipment side. 3) Open the stop valve on PG-20-8″, open the large outlet valve 104-DB, open the stop valve on A-20-10″, slowly close the stop valve on A-25-4″, and purge the pipeline of 8″ size until it meets the requirements. 4) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 5) For the shut-off valves on PG-10-18″ and PG-20-8″, remove the blind flange at the 105-CA/CB process gas inlet and reset the flanges. 3.4.5.8.9 Purge PG-21-4″ and PG-1001-3″ pipelines 1) Disconnect the flange before the second valve of PG-1001-3″. 2) Open the two shut-off valves on PG-21-4″, and open the first shut-off valve on PG-1001-3″. 3) Open the stop valve on A-20-10″, slowly close the stop valve on A-25-4″, and purge the pipeline in “9” until it meets the requirements. 4) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 5) Close the two shut-off valves on PG-21-4″, close the first shut-off valve on PG-1001-3″, and restore the flange in front of the second valve on PG-1001-3″. 3.4.5.8.10 Purging of N-15-18″ pipeline 1) Disconnect the process gas inlet flange of C66404 and install a blind flange on the equipment side. 2) Open the stop valve on N-15-18″, open the stop valve on A-20-10″, slowly close fully the stop valve on A-25-4″, and purge the pipeline in “10” until it meets the requirements. 3) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 3.4.5.8.11 Purging of N-16-18″ pipeline 1) Disconnect the inlet flange of F66401 and install a blind flange on the equipment side. 2) Open the stop valve on A-20-10″, slowly close the stop valve on A-25-4″, and purge the pipeline in “11” until it meets the requirements. 3) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 4) Remove the blind flange in “(1)” and reset the flange. 3.4.5.8.12 Purging of N-17-18″ pipeline 1) Disconnect the inlet flange of J66402 and install a blind flange on the equipment side. 2) Close the shut-off valve on V-45-8″. 3) Open the stop valve on A-20-10″, and slowly close the stop valve on A-25-4″. Blow out the pipelines in “12” until they meet the requirements. 4) Open the stop valve on A-25-4″, and close the stop valve on A-20-10″. 5) Remove the blind plate in “(1)” and reset the flange. Restoration work after purging 3.4.5.10.1 Restoring the \"8\"-shaped blind plates and flanges after the FRCA-2 valve and bypass valve. 3.4.5.10.2 Restore the “8”-shaped blind plate and flange after the MIC-19 valve. 3.4.5.10.3 Install check valve spools on the A-20-10″, MS-29-12″, A-21-10″, NG-6-8″, PG-1001-3″, NG-15-3″, and NG-14-3″ pipelines. 3.4.5.10.4 Install the FT-3, FT-4, FT-30, FT-31, FT-58, FT-400 flow orifice plates. Close the flange. 3.4.5.10.5 Remove the blind flanges in front of the safety valves RV-4, RV-19, RV-42, RV-112, RV-132, RV-143, RV-181, RV-182, RV-188, RV-191, and reset the flanges. 3.4.5.10.6 Remove the inlet pipeline of the raw material gas preheating coil, remove the flanges on the inlet pipelines of the mixed raw material gas preheating coil and the air preheating coil, and restore the pipelines. 3.4.5.10.7 Reinstall FCV-4A, HCV-8, TCV-10, TCV-11, SP-4, MIC-26, SP-2, FCV-1, FCV-12, PCV-69, PCV-1, HV-1030. 3.4.5.10.8 Remove the stop valves at valves FCV-4, SP-3, and SP-5, and reinstall FCV-4, SP-3, and SP-5. 3.4.5.10.9 Remove the stop valve at the far end of the intake manifold and weld a new pipe cap back on. 3.4.5.10.10 Reinstall the demister inside F66401. 3.4.5.10.11 Remove the short circuit on NG-45-3″ and install the filter screen. 3.4.5.10.12 Remove the top flanges of the 336 furnace tubes, and use a vacuum pump to evacuate the 336 furnace tubes thoroughly. Re-close the flange at the top of the furnace tube. 3.4.5.10.13 Disassemble flange 107-D and manually clean the dirt inside 107-D. Re-close the 107-D flange. This post was last edited by Huang Xinhui on 2009-3-17 at 17:56.]