Weekly Topic (9.26-10.8): How to effectively monitor the thermal expansion and displacement of equipment and pipelines in order to detect potential hazards promptly.
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This post was last edited by lijianhuai on 2011-10-7 09:07. The weekly topic discussion event in the refining area welcomes active participation from everyone; we also hope that people will come up with more valuable topics, and the moderators will award rewards of 5-20 wealth points. Those who post excellently will receive a reward of 10 to 50 Wealth or an equivalent amount of Charm. 9 X6 i! S. F, |9 V* _8 @' D& t Please do not hide your responses to this question. In the oil refining and chemical industry, the processes are complex, with significant variations in parameters such as temperature and pressure. Various equipment and pipelines experience noticeable thermal displacement due to heat expansion and contraction; especially during start-up/shutdown operations or when there are fluctuations in production, the displacement can reach several centimeters or even more, leading to excessive local stresses. Issues such as the failure of support structures or elastic components, or the use of unsuitable materials for gasketing, can directly lead to dangers like leaks. Routine inspections of components such as pipelines and support elements cover large areas and involve a large number of items, which often result in blind spots and make it difficult to detect potential problems in a timely manner. I hope everyone will discuss how to effectively monitor the thermal expansion and displacement of equipment and pipelines during daily operations, in order to identify and eliminate potential safety hazards in a timely manner.
Reply 1# dongliangsir: Generally, high-temperature pipelines are equipped with fixed pipe supports and sliding pipe supports. Position markers can be placed on these supports before operation begins; during the heating process, the displacement of these markers is monitored. If the displacement reaches the designed value, appropriate action should be taken promptly； The equipment also needs to be marked, and it is sufficient to observe and take action carefully during the operation process ； If any bumps are detected during the construction process, they should be addressed promptly
Primarily, inspections of the pipelines are carried out at the time of initial operation; during normal operations, inspections focus on the key areas
When we started working, I marked the ductwork for the smoke extractors, and the thermal displacement was quite noticeable! In normal production, I think it’s necessary to regularly inspect the pipelines in key areas and address any abnormalities promptly.
This post was last edited by jbcyf on 2011-10-3 08:04. During the initial installation of the piping in front of our exhaust fan, various reasons such as the low skill level of the workers led to failure to follow the design specifications, and pre-stretching was not carried out. Problems emerged early in the project’s commencement: first, there were leaks at the flanges; lateral expansion caused the hinges of the pipeline expansion joints to break, and the expansion joints in the outlet vertical pipe sections also encountered issues to varying degrees... Although adjustments were made during two maintenance sessions, the problem could not be resolved fundamentally. Therefore, during the installation of the equipment, it is essential to follow the specifications precisely, especially when dealing with heat pipes and high-temperature components; special attention must be paid to any existing issues to avoid creating potential problems later on in the operation of the facility. By the way, I would like to ask the experts: given the current situation of our equipment, how should we deal with it? Thanks first!
The stress generated in chemical processes is primarily caused by changes in temperature and pressure; therefore, these factors must be taken into full consideration during design. The maximum stress that occurs under different conditions should be assessed, and expansion joints, active supports, or hangers should be added according to the actual production requirements.
This post was last edited by lijianhuai on 2011-9-30 at 13:42. This problem is more pronounced in the northern regions, mainly affecting steam and heat transfer oil pipelines. Although sliding supports and thermal expansion bends are used as safeguards, issues such as the failure to remove internal condensation from the steam pipelines in a timely manner during the initial operation phase, along with excessive temperature rises, can lead to accidents.