How can we avoid high-temperature oil and gas leakage fires, as well as the extremely risky emergency pressure-containing leak sealing operations?

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Firstly, it is the online monitoring and prevention of flange sealing conditions. This is not a detection and alarm system for toxic, harmful, flammable, and explosive gas concentrations as specified in the \"GB/T 50493-2019 Design Standards for Detection and Alarm of Flammable and Toxic Gases in Petrochemical Industries.\" Gas concentration detectors are generally installed at a distance of 0.5–1.0 meter from the sealed points; they can only detect leaks when they are quite large (LDAR can detect leaks at levels of 20,000–30,000 μmol/mol, while at a distance of 0.5–1.0 meter from the leak site, the concentration is only a few or dozens of PPMV or μmol/mol) ； Secondly, strong winds blow at high elevations; moreover, the dominant and secondary wind directions vary depending on the season or month. The density of high-temperature hydrogenated C1-C2 light hydrocarbon mixtures is generally lower than that of air, so they disperse upward with the wind after a leak occurs. Therefore, deploying just 1 or 2 concentration detectors often fails to serve the purpose of monitoring and warning against flange leaks. Furthermore, the explanations in clauses 4.1.4, 4.2.1, 4.2.2, 4.2.3, and 6.1.2 of standard GB/T 50493-2019 state that for release sources located in open and high areas, if the leakage amount is low and the scale of such sources is small, resulting in no hazardous environment, it may not be necessary to install sensors – is this because the cost of wiring such old devices in use is too high, or because the detection rate is too low? An online continuous monitoring and prevention system for the condition of critical sealing points, unaffected by weather conditions, is capable of detecting even the smallest leaks at flange seals that are prone to leakage on the top of tanks or beneath insulation layers. It automatically sends yellow or orange alarm signals to those responsible for static sealing points or equipment integrity management, informing them promptly: \"Owner, I’m starting to leak; please pay attention to me😢.\" Secondly, what should be done in the event of a flange leak? Similar to vibration monitoring of pumps or compressors, the purpose of seal condition monitoring is to enable predictive maintenance. In the past, the timing of thermal tightening for flanges connected to high-temperature oil and gas was determined mainly based on experience. If leakage persisted even after a second tightening attempt (the sealing surface having been damaged by the high-speed flow of oil and gas), further tightening only made the leakage worse, until the gasket was crushed and no longer functional; in such cases, alternative temporary measures such as replacing the gasket or performing leak sealing under pressure were required, forcing the installation to operate despite its defects. When dealing with leaks, it is important to note that as soon as a leak is detected, a decision must be made at the site of the leak (within a safe area) regarding whether to take action and how to do so, as quickly as possible. There should be no unnecessary demands on frontline employees to prepare numerous forms and documents in meeting rooms, such as those requiring an analysis of the causes or determination of responsibilities, followed by cross-departmental approval processes. What matters is to address the leak promptly, rather than trying to create records to prove that one has fulfilled their duties properly. Otherwise, it may lead to minor leaks that could be handled locally not being reported even after they have been dealt with (due to the requirement to fill out many forms), and reports are only made when it is no longer possible to handle them locally (which may result in missing the optimal time for handling them). Predictive maintenance is far cheaper than reactive pressure sealing for leaks and conditional preventive maintenance. Maintenance costs for oil refining and chemical enterprises typically account for 15% of production costs ； In the United States, companies spend over $200 billion each year on maintenance costs, of which one-third is wasted. China’s refining and petrochemical production scale has been the largest in the world since 2022; will the amount of waste generated be less than that of its American counterparts? (As shown in Figure 3, one drop should be applied every 3–4 minutes to the flange; if the thermal tightening safety measures are not in place, thermal tightening can be postponed for now.) Thirdly, this applies to the sealing points of high-temperature oil and gas flanges on critical equipment. High-performance gaskets capable of withstanding alternating high and low temperatures as well as creep relaxation should be used, in combination with high-precision torque-controlled fastening and online continuous monitoring of the sealing condition to implement predictive maintenance, thereby avoiding emergency repairs under pressure or unplanned partial shutdowns to address issues. For those high-temperature oil and gas pipeline flange seals with excellent stress distribution and stress level design, insulation layers can also be installed as required by the design, which is energy-saving and environmentally friendly, reduces energy consumption, and achieves two goals at once!