[Safety Article] Knowledge on Safe Operation of Pressure Pipelines

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At around 15:20 on August 11, 2016, an explosion occurred in a high-pressure steam pipeline at Madian Gangshi Power Generation Co., Ltd. in Dangyang City, Yichang Province, Hubei Province. The accident resulted in 21 deaths and 5 injuries, 3 of whom were seriously injured. How then can pressure pipelines be operated safely? Here are a few brief suggestions for everyone: The regular maintenance of pressure pipelines is an important foundation for ensuring and extending their service life as well as preventing accidents. Operators of pressure pipelines must carry out proper daily maintenance of such pipelines: 1. Regularly inspect the protective measures in place on the pressure pipelines to ensure they are in good condition, thereby reducing corrosion on the pipeline surface ； 　　2. The operating mechanism of the valve should be regularly descaled and oiled, and operated periodically to ensure smooth operation ； 　　3. Safety valves and pressure gauges should be wiped regularly to ensure their sensitivity and accuracy, and calibrated on schedule ； 　　4. Regularly check the condition of the fastening bolts to ensure they are complete, free from rust, have intact threads, and provide a reliable connection ； 　　5. Pay attention to the vibration of the pipes; in case of abnormal vibration, take measures such as isolating the source of vibration and strengthening supports to reduce vibration, and take action promptly if friction is detected ； 　　6. Static bonding and grounding devices must be in good condition; any damage detected should be repaired promptly ； 　　7. Decommissioned pressure pipelines should have their internal media removed, and they should be replaced, cleaned, and dried; inert gas protection may be applied if necessary. The outer surface should be protected with paint; for pipes with insulation, ensure that the insulation material is in good condition ； 　　8. Inspect areas prone to corrosion and wear, such as the contacts between pipes and supports, and take measures promptly if any issues are found ； 　　9. Eliminate leaks, drips, and other issues in the piping system promptly ； 　　10. For high-temperature pipelines, the flange connection bolts must be tightened thermally during the startup heating process ； For low-temperature pipelines, cold straining is carried out during the cooling process ； 　　11. It is prohibited to use pipes and supports as neutral wires for electric welding or as anchor points for other tools, or as support points for lifting heavy objects ； 　　12. Cooperate with pressure pipeline inspectors to conduct regular inspections of the pipelines ； 　　13. Pressure pipelines in critical sections of the production process, those that pass under roads, bridges, railways, and rivers, as well as those that run through residential areas, pipelines transporting flammable, explosive, toxic, and corrosive substances, pipelines operating under harsh conditions, and pipelines subjected to alternating loads should be given priority in terms of maintenance and inspection ； 　　14. In the event of the following situations occurring during operation, emergency measures should be taken immediately, and the relevant management departments and supervisors should be informed promptly: (1) The pressure and temperature of the medium exceed the allowable limits, and no improvement is seen even after taking measures ； 　　(2) Cracks, bulging deformation, and leaks in pipes and their components ； 　　(3) Freezing blockage of pressure pipelines ； 　　(4) Abnormal vibration and noises in pressure pipelines, posing a threat to safe operation ； 　　(5) Failure of safety protection device ； 　　(6) A fire accident occurs, posing a direct threat to normal safe operation ； 　　(7) Failure of the valves and monitoring devices in pressure pipelines endangers safe operation.