Urgent! Urgent! Urgent! Why is a jacket used for insulation when evacuating a pipeline?

There should be other production processes to consider; otherwise, vacuuming alone would not require a jacket for insulation.

Ensure the vacuum level of the pipeline and protect it from external influences.

It’s related to the properties of your process materials; there are requirements regarding the temperature of the pipes! Otherwise, it will solidify and block the pipes.

The jacket definitely has nothing to do with vacuuming; it’s used solely for heating or cooling. Of course, if a vacuum is created using the jacket, that’s another matter. A jacketed vacuum system is intended for insulation, but it must be quite expensive, right?

I’m not sure if it’s right? Everyone can discuss it now.

We don’t know the exact reason; logically, when the vacuum reaches -0.097 MPa or around that level, water should boil at a temperature of just over 10 degrees Celsius (below its saturated vapor pressure). Yet we have indeed encountered such a problem: the vacuum pipes freeze over in winter! The pipeline configuration is improper, as there are liquid pockets; moreover, the ambient temperature has reached -20 degrees, and the vacuum pump used is a water jet pump. Moreover, it is common for condensate water to form in vacuum pipes; this is probably because the temperature of the equipment is higher than that of the pipes, resulting in the formation of steam inside the equipment under the same vacuum conditions. This steam then condenses within the pipes. I’m not sure about the situation you’re referring to, but jacket insulation is intended to prevent changes in ambient temperature from causing the pressure inside the pipes to reach the saturation vapor pressure, which could lead to freezing, or for some other reason as well. I hope it helps. Let’s see what others have to say. This post was last edited by Pseudo Xiao Bao on 2009-4-18 at 23:45.]

The pipeline is evacuated, and the gas drawn back is not necessarily air; in most cases, it is part of the process gas from the reaction vessel. Therefore, it is necessary to take into account the specific properties of this process gas in order to provide jacketing for insulation or cooling. This is my understanding; please point out any mistakes O(∩_∩)O~

It is related to the properties of the process materials. If the material to be distilled has a low freezing point, a high vacuum level is generally required; as a result, a small amount of light components will be carried into the vacuum pipeline. If the vacuum pipeline is long, these extracted light components will condense within it, and over time this will have a significant negative impact on both production and the vacuum pump. The poster can consider their own manufacturing processes and materials.

Are you referring to a vacuum jacket? Logically, if the pipe jacket is evacuated, there will be no medium available to transfer heat; as a result, the heat transfer coefficient with the outside environment will be very high, and it would then not be necessary to use an insulating jacket. In the projects we work on, vacuum jacketed tubes do not require any insulation layer. I’m not sure if the real tube you’re referring to is the same as ours ?

In the evaporation and concentration section of the urea plant, the process pipes of the vacuum system are jacketed, with the main purpose being to prevent urine crystals from causing blockages!

The temperature of the pipeline can have a significant impact on the vacuum pumping process; insulating it can reduce the power required by the vacuum pump, thereby saving on operating costs. This is just my personal opinion, for reference only!

In my opinion, during vacuum pumping, the amount of gas removed is proportional to the temperature. A lower temperature is preferable for simple vacuum pumping; however, the use of jackets and insulation allows the temperature of the material to be kept within a certain range regardless of the season.

Ensure vacuum level remains unaffected by external factors

Use in low-temperature environments; not use in high-temperature environments.

Generally, a condenser should be placed before the vacuum pump to allow some of the steam to condense and flow into the liquid collection tank, thereby reducing the load on the vacuum pump. Adding a jacket for insulation here is probably related to the manufacturing process; if there are crystalline materials that need to be drawn out, it’s better to have a jacket. Once crystals clog the vacuum pipeline, it may be necessary to shut down the plant.

The specific circumstances are not clear; generally, water vapor in the air will freeze under vacuum at 10 degrees. After freezing, it takes a long time to achieve the desired level of vacuum, especially in medium to high vacuum conditions

It is determined by the process conditions; presumably, the process medium requires cooling. Additionally, vacuum pump stations are of such a type that they may have requirements regarding the gas entering them, requiring the rapid condensation of harmful substances in the medium.

There must still be crystallizable vapors in your vacuum system; otherwise, a thermal insulation jacket is generally not needed

It is mainly related to the properties of the material being sampled； When the freezing point of the material is below room temperature and the pipes lack insulation, the material tends to freeze inside the pipe walls, causing blockages that affect the vacuum pumping efficiency.