[Q&A Question 157] 2017.06.06
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This post was last edited by 955559 on 2017-7-21 23:14. [Q&A Question 157] June 6, 2017: How to prevent freezing in heating pipelines? The reference answers can be seen after *responding*; points will be awarded for identifying the key points. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) 1. Conduct thorough inspections and address any issues found promptly; 2. When the water lines and tanks are not in use, clean them thoroughly, either by opening them or installing blind flanges; 3. Use the tanks for heating when the installation is shut down; 4. Maintain good insulation conditions, and repair any damage immediately; 5. Strengthen maintenance to ensure proper operation. Scoring criteria: 2 Wealth points for incorrect responses; *incomplete* answers earn 3–8 points. 10 Wealth points are given for correct answers accompanied by detailed explanations; responses that are correct but lack sufficient details earn 15–20 Wealth points. Please score according to these criteria. Note: If there are editing records after answering, only those who participated will be given points. For continuous malicious spamming, 2 points will be deducted each time, with no upper limit. Pure numbers, pure emojis, or random letters unrelated to the answer are all considered malicious spamming; points will start to be deducted after three warnings. 2017 Q&A Summary Thread (updates starting now) http://bbs.hcbbs.com/thread-1657793-1-1.html 2017 Daily Question Summary Thread (updates starting now) http://bbs.hcbbs.com/thread-1657794-1-1.html 2016 Q&A Summary Thread (updates completed) http://bbs.hcbbs.com/thread-1597792-1-1.html
1. Conduct thorough inspections and make timely corrections whenever issues are found. 2. When the water lines and tanks are not in use, clean them thoroughly, either by opening them or by installing blind flanges. 3. Use the tanks for heating when the installation is shut down. 4. Maintain good insulation; repair any damages promptly. 5. Strengthen daily maintenance to ensure normal operation.
During operation, ensure proper insulation and drain the liquid at regular intervals. Upon shutdown, drain the liquid, purge it with nitrogen, and maintain a slight positive pressure.
Reference answers: 1. Conduct thorough inspections and make timely corrections whenever issues are found; 2. When the water lines and tanks are not in use, clean them thoroughly, either by opening them or by installing blind flanges; 3. Use the tanks for heating when the installation is shut down; 4. Maintain good insulation conditions, and repair any damages promptly; 5. Strengthen maintenance to ensure proper operation of the system.
(1) All heat tracing valve assemblies within the unit are in normal operation, and the heat tracing return water flow is unobstructed. The heat tracing and return water in use have no leakage points. (2) The equipment, pipelines, and instruments are well insulated; the insulation layer is intact, thick enough, and the surface temperature does not exceed 60°C. (3) Equipment and pipelines that are not in use for a long time must be fitted with blind flanges to isolate them from the production system; any water stored within them should be drained, and the areas should be cleaned using industrial air. For equipment that is left unused outdoors as well as those that are in operation, anti-freezing measures such as surface protection should be implemented to prevent water accumulation from freezing or snow from damaging the equipment; regular inspections should also be carried out. (4) For water and steam pipelines that are temporarily shut down for production purposes, as well as equipment that is temporarily out of service, anti-freezing and anti-condensation measures must be in place. The pipelines should be thoroughly cleaned after the supply of water or steam is stopped. (5) For heavy oil instruments, critical instruments, and instruments using water or steam as the medium, it is necessary to ensure that the heat tracing function is effective and that proper insulation is in place. If there is no heat tracing or insulation, a plan must be submitted to add heat tracing and insulation. (6) Underground valve chambers, fire hydrants, and pipe trenches should be inspected one by one; the accumulated water should be pumped out using a water pump, and then covered with stone cotton blankets. (7) All circulating water coolers must be in normal operation, with the bypass valves kept at a slight open position to maintain flow. (8) In principle, the heating coils of each device should be put into normal operation, and it is necessary to ensure smooth return water flow. In the event of abnormalities such as coil leakage, anti-freezing and anti-condensation measures must be taken after shutting it down. (9) Frost and condensation prevention risks must be identified at the reserved ports and condensate drainage points of various equipment; for those with such safety hazards, corrective measures such as adding heat tracing and insulation should be taken.
Install traps appropriately in steam pipelines； Ensure proper drainage and drying when shutting down
The insulation panel gets hot; clean it thoroughly before use when it’s not in use
Conduct thorough inspections and address any issues found promptly. When not in use, purge it thoroughly or apply a blind flange. Good insulation, with any damage addressed promptly. Hydrogenation maintenance
1. Conduct thorough inspections and make timely corrections whenever issues are found. 2. When the water lines and tanks are not in use, clean them thoroughly, open them or install blind flanges. 3. Use the tanks for heating when the installation is shut down. 4. Ensure good insulation; repair any damages promptly. 5. Strengthen maintenance to keep the system operating properly.
Add a heat tracing line, or keep the medium in constant flow