Regarding the issue of leaking heat exchangers
Thread Content
I’m just a newbie when it comes to equipment; may I ask the more experienced folks here. Are there any other methods for sealing leaks in tubular heat exchangers besides welding them shut using fire? Because some heat exchangers do not meet the conditions for hot work. If so, please be a bit more specific. What is the typical margin for tubular heat exchangers? A certain degree of blockage does not have a fundamental impact on the efficiency of the heat exchanger. Is the heat transfer efficiency of stainless steel lower than that of carbon steel at the same heat transfer area? It’s best to explain the reason.
If it is not the heat exchange tube itself that is broken, it is best not to plug the tube; nor should welding be used for plugging, as this will affect the sealing of other tubes. For heat exchangers under low pressure, metal plugs can be inserted to block the tubes.
To seal leaks in tubular heat exchangers, welding is generally used; if the conditions for welding are not available, the system can be purged first to make welding possible. This is the case in many situations in chemical production. Of course, there are also leak-sealing tools; imported ones can cost up to 10,000. Different adhesives are used depending on the material, which is also very convenient. The typical margin for tubular heat exchangers is 10%, and within this range it generally has no significant impact on the efficiency of the heat exchanger. At the same heat exchange area, stainless steel has a slightly lower heat exchange efficiency than carbon steel, as its thermal conductivity is slightly lower, which in turn results in a lower heat transfer coefficient.
The thermal conductivity of carbon steel and stainless steel is different
Where is the leak? Our company can perform leak sealing under pressure on-site; if the issue is caused by an uneven surface, we can use portable machining tools to carry out on-site repairs.
Thank you all for your responses. The leak in the heat exchanger is due to a problem with the tubes; work cannot be carried out because it’s not possible to purge the shell side, or the purging isn’t thorough enough. This is because the pipes and valves connected to the shell side have some internal leakage, and they are welded valves. So, methods other than using fire need to be considered. A friend mentioned using metal to block the pipe; could you be more specific about what kind of metal, such as aluminum? Copper? Or something else. A friend suggested using glue; could you please tell me the specific name and specifications of this glue, as well as its approximate price? A friend mentioned pressure-based leak sealing; I’m not sure what the cost is
Our company usually first seals the leaking pipe with a conical plug made of the same material as the pipe, and then welds the plug to the tube sheet. Eliminate leakage points. I’m also very curious to know what kind of glue is used for bonding. We also have many heat exchangers that are difficult to hand over. Also, how long does it take for the glue to cure? If it’s for emergency repairs. The time cannot be too long.
Plugging leaks under pressure involves certain risks. Our company’s new technology, protected by a U.S. patent, involves installing a special washer beneath a regular nut; by precisely controlling the bolt loading force, zero leakage can be achieved. This technology is currently being widely used in China’s petrochemical industry, with many successful applications