Are there any methods to prevent freezing in steam tracing pipelines?
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Preventing freezing and condensation in the pipelines of refineries in the Northeast region during winter is a significant challenge; even the slightest carelessness can lead to freezing of the steam-heated pipelines, forcing workers to remove the insulation from those pipelines and use steam to thaw them out. It is time-consuming and labor-intensive, and the operators have to work together in the cold wind to blow the pipes. Is there a better way to deal with frozen steam pipelines?
If freezing occurs, it is important to first clear the areas that are difficult to reach; once those areas are cleared, the rest of the system will become unobstructed with just a little cleaning. Of course, it’s best to pay close attention during regular inspections and take action before freezing sets in, as this saves time and ensures safety.
The main focus is on strengthening inspections to detect and address issues early.
Isn’t preventing freezing and condensation achieved by keeping the heat trace valve slightly open? With a small amount of steam flowing, condensation won’t occur
If the pipeline to be insulated can be heated, its temperature will rise, and the steam insulation wire will melt.
Remove the insulation, connect the temporary heating wire with a rubber hose, and then supply steam – it becomes operational quickly. It is equivalent to adding a temporary bypass line.
Reply 1# jzycf: This situation usually occurs when the heat tracing is disabled, right? For heat tracing that is used intermittently, after each shutdown, non-purified air can be used to blow out the condensate water in the pipes; once it’s time to use the system again, the heat tracing can be activated and flow will be established immediately. Therefore, a drain valve should be installed before each heat tracing system to facilitate the connection to the unpurified air line. And ensure that the blown-out pipeline cannot be connected to steam again.
Historical experience tells us that the most important thing is to check regularly to avoid freezing; if freezing does occur, then everyone must work together to warm it up. Many people mean great strength, so there must be enough team members!
Thermal insulation pipelines should be cut at corners, low points, and other areas prone to freezing, and then purged in sections; tape should be used for sealing. When performing these operations, make sure the steam flow isn’t too high, and the purging steam shouldn’t be turned on continuously – it should be used intermittently. There are also coordination issues related to the use of steam. In our company, there was an incident where the steam flow suddenly became unobstructed, causing the steam lines at 90-degree angles to straighten out, which resulted in someone being injured fatally
Heated freezing is rarely heard of. 1. It may be due to reasons such as too low steam flow or discontinuity. 2. There are issues with the process design. 3. The filter screen of the steam trap is clogged. 4. The pressure difference in the feed and exhaust systems is too low, and the low flow rate leads to freezing. 5. Inadequate management: supervisors do not participate in or give due attention to anti-freezing inspections and supervision, resulting in gaps in routine inspections of various locations. 6. The climate is extremely extreme, requiring an increased amount of heat tracing steam.
I won’t go into the common practices used in refineries; instead, I’ll mention something unique to this particular plant: a water separation pack can be installed along the pipeline to remove water from it. Multiple pipelines can share one