Fixed-tube-sheet heat exchanger
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There is currently a soda water heat exchanger with the model number: BEM1200-1.47/0.98/500/5.4/32-2I. As can be seen from this model number, it is a fixed-tube-sheet type heat exchanger, with a heat exchange area of 500 m2； The design pressure of the pipe train is 1.47 ； The design pressure for the shell side is 0.98. That means the steam flows through the tube side, while the water flows through the shell side, right? Can the design temperatures for the tube side and shell side be determined based on this model?
The basic parameters you provided are correct, but it’s still difficult to determine whether the steam should flow through the tube side or the shell side of the heat exchanger. I did the calculations; at 0.98 MPa, the steam pressure is quite high. It should be 0.98 kilograms, right? Its saturation temperature is 99.4 degrees, while that of 1.47 kilograms is 110 degrees; both can be used as heating media. So it’s hard to determine whether steam is moving on that side. The design temperature is also hard to determine, in my personal opinion. As a supplementary point, in this case, it’s better for the steam to flow inside the pipes, right? Hope the answer is given below. Last edited by wode*aohei on 2009-2-24 12:27.]
Based on the model explanation in 151, it should be as mentioned on the first floor: the pressure is 0.98 MPA, not 0.98 kilograms.
If the pressure of the steam is 0.98 MPa (g), the saturated steam temperature is approximately 180 degrees； If the pressure of the steam is 1.47 MPa (g), the saturated steam temperature is approximately 200 degrees; it’s indeed not possible to determine which path the steam will take.
I also know what the regulations stipulate in GB151, but it’s really uncommon to use steam at such high pressure as a heat source. It would be great to use such a heat source as power. Not recommended for use. It can be used as a heat source after using power.
Agree with the person above: it’s really uncommon to use steam under such high pressure as a heat source. It would be great to use such a heat source as power. Not recommended for use. It can be used as a heat source after using power. :victory: :victory: :victory:
For BEM1200-1.47/0.98/500/5.4/32-2I, the value 151 indicates that the design pressure for the tube side is 1.47 MPa, while the design pressure for the shell side is 0.98 MPa. The heat exchange area is 500 square meters, the tube length is 5400, and the tubes have a diameter of φ32; they are high-grade cold-drawn heat exchange tubes. Furthermore, the design pressure does not represent the operating pressure; it is the operating pressure that corresponds to the respective steam temperature. This post was last edited by Perseverance on 2009-2-25 19:30]
Everyone has analyzed it well, but it’s not necessarily steam that flows through the tube side; it should be some kind of process gas
To add to what everyone has said, high-pressure steam can indeed be used as a heat source; our factory uses steam at 6.4 MPa and 275 degrees Celsius as the heat source. As for the issue mentioned by the original poster regarding which fluid should flow through the tube side, I believe water should flow through the tube side, as water tends to form scale, and it’s easier to clean the tube side in such cases. If water flows through the shell side, the heat exchange efficiency will drop significantly
According to control principles, since the control variable is the temperature of the water, it would be better for the water to flow through the tube side and the steam to flow through the shell side, right? :lol
1. It is impossible to determine which medium takes which path for this model. There is no necessary connection. Because steam can be in a saturated or superheated state, while water is mostly in a subcooled state. 2. The design temperature cannot be determined either. The reason is the same as above.
The steam should flow through the shell side, while the water flows through the tube side. The tube train is easy to clean. As the original poster asked, can the design temperatures for the tube side and shell side be determined based on this model? In my personal opinion, no.
I read the original poster’s post a long time ago; at that time I wanted to provide an answer, thinking I had seen this number before but wasn’t sure, so I searched the internet but found no relevant information. A few days ago, a group of us technical experts organized a training session led by a foreigner, and a large part of it was dedicated to TEMA design. There were examples given, and the numbering for shell-and-tube systems was of that type. For now, all I can tell you is that it is designed according to TEMA standards; as for the detailed meanings of the parameters, I need to consult the teaching materials. He said he would give us a CD, but it hasn’t arrived yet. Once it does, I’ll provide a detailed explanation
There is also data on the pressure tolerance limit on the side of the cooling tube shell; I will compile it all and provide it once the disk arrives
The moderator is right; with higher steam pressure, it should be routed through the tube side； Water flows through the shell side.
A pressure of 0.98 MPA is a bit high. It depends on the type of water being used; if scaling isn’t a concern, it’s recommended to use steam in the pipe network
I did the calculations; at 0.98 MPa, the steam pressure is quite high. It should be 0.98 kilograms, right? Its saturation temperature is 99.4 degrees, while that of 1.47 kilograms is 110 degrees; both can be used as heating media. So it’s hard to determine whether steam is moving on that side. The design temperature is also hard to determine, in my personal opinion. As a supplementary point, in this case, it’s better for the steam to flow inside the pipes, right? Hope the answer is given downstairs
Generally, steam flows through the shell side, while water flows through the tube side. Because the specific volume of steam is large; otherwise, the flow velocity would be very high. Additionally, the design temperature cannot be determined for this model, as there may be superheated steam; it can only be determined after considering the operating parameters. I judge that steam flows through the shell side, and water flows through the tube side.
In my opinion: water flows through the shell side, while steam flows through the tube side.
From the perspective of cleaning and maintenance of heat exchangers, water should flow through the tube side while steam flows through the shell side, as water tends to form scale. After the heat exchanger has been in use for some time, scaling will inevitably occur on the side where water flows. Since fixed-tube-sheet heat exchangers cannot have their tubes removed, if water flows through the tube side, the tube box and end caps can be taken off after scaling forms, allowing the scale to be removed using a high-pressure water gun. If water flows through the shell side, it cannot be cleaned.
If scaling is not considered, water flows through the shell side while steam flows through the tube side.