In winter, when the anti-freezing heating for pipelines freezes up, how do people deal with it?
Thread Content
Our anti-freezing work is very demanding; the heat tracing often freezes up, making it difficult to clear the blockages. How does everyone handle it?
How could the heat tracing get frozen? It’s likely that a U-bend is present, causing liquid resistance. . .
It is likely heated with hot water; there might be iron shavings or similar substances inside the pipes that have accumulated, causing poor flow. Steam can be used to blow into the insulation material, and if it’s too long, it can be blown on in sections.
In the case of steam tracing, as long as the condensate is drained promptly, freezing will not occur. We all have dedicated personnel responsible for arranging for condensate to be removed at specific points. If it really freezes solid, make a cut in the middle of the entire pipeline and blow it out with steam
The heat tracing line should be designed with an appropriate length and layout, and it must be purged thoroughly before being put into use； During the trial run, the problematic heat trace was fixed to ensure smooth operation ； If freezing occurs, open the vent valve; blow upward along the vent valve ； Without a vent valve, the heat trace has to be sawed open, cleared, and then welded back together. The key to heat tracing work in winter is to conduct inspections on schedule; by detecting issues promptly, it becomes easier to address them.
It can only be done by blowing with steam, in sections. In winter, we generally maintain low levels of emissions; the most important thing is to carry out inspections on schedule.
This depends on the medium flowing in the pipeline that is subject to freezing and heating. If only the insulation layer freezes while the main pipeline has not frozen, it is possible to install vent valves at both ends and use steam for purging in order to reverse the heating process, which makes things faster to resolve. If the main pipeline also freezes, things become more complicated; in such cases, steam must be used for segmental purging, or else the heating system might have to be abandoned depending on the operating conditions of the pipeline.
As long as the heating steam is supplied, freezing will not occur; does the situation you described involve the heating line freezing during shutdown? If so, it is possible to use air to expel the condensed water from within the heating line before shutting down.
Our heat tracing system still has many problems: some sections of the heat tracing have branch lines, and those branches with high resistance often freeze over； In some cases, the heat tracing is too long, resulting in insufficient steam pressure and poor return flow ； Some pipes are rusted, which blocks the steam traps, and so on! Ugh, it’s been windy all morning again; the insulation material has gotten wet, so its insulating effect must be poor now. It needs to be replaced during maintenance! ! !
If the heat tracing wire freezes easily, first consider whether its length is appropriate; secondly, check whether the backflow pressure of the heat tracing wire is unstable, which could lead to poor backflow. If a float-type steam trap is used, occasional water hammer in the pipelines may cause the float to crack, preventing the steam trap from functioning properly. Verify whether the steam trap is working correctly.
It can only be blown with steam. During winter, inspections should be intensified; the fire suppression steam should be turned on slightly, while the steam used for line cleaning should have its valve opened to allow air flow. The heat tracing systems also need to be checked regularly