Selection of gaskets for detachable plate heat exchangers
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This post was last edited by wwyyxxz on 2024-6-20 at 15:00. We have a project that requires detachable plates, and the materials involved are exposed to temperatures of 130°C. Is it feasible to use EPDM gaskets in this case?
, right? Both the temperature and the medium are suitable
Using EPDM gaskets to handle materials containing propylene at 130°C may not be very appropriate. Although EPDM gaskets have good heat and chemical resistance, they do not tolerate propylene well and are prone to corrosion by it. It is recommended to choose materials that are more suitable for resisting propylene, such as PTFE gaskets. This material offers excellent chemical resistance to propylene, and its high-temperature tolerance also meets the requirements of your application. .
This post was last edited by In silence on 2024-6-21 at 10:19. Feel free to take the attachment; no need to thank me. Using PTFE on the plate exchanger as a gasket is a bold idea – truly exceptional. 1. PTFE exhibits cold flow properties, and it may undergo creep under prolonged pressure, leading to leakage; it is not as reliable as gasket materials that can maintain a seal along multiple lines. In practical applications, fiber reinforcement or an outer ring is used to enhance its performance. With the winding shape of the plate heat exchanger sealing surface and its unevenness, the likelihood of problems arising after compression increases significantly. So, whether or not there is propylene, PTFE is basically rarely used as an inter-plate gasket. 2. PTFE has a low pressure strength; once it is installed, it becomes useless if removed. When cleaning and repairing plate heat exchangers, it isn’t necessary to replace all the gaskets, but with PTFE, all of them have to be replaced. 3. Pure PTFE has weak rebound properties, and modified expanded or reinforced PTFE also shows little rebound when compressed (since the modifying additives can have negative effects as mentioned in point 4); it is unable to cope with even minor changes in the gap between the plates that occur due to alternating hot and cold conditions when the heat exchanger starts operating. In summary: leakage is basically inevitable. 4. Hot acetone is quite remarkable: according to the material manual, PTFE is insoluble in any solvent, and therefore bronze in this type of solvent is not affected by it. However, PTFE does swell when exposed to hot acetone (the degree of swelling varies depending on purity and the amount of cross-linked substances). Based on my practical experience on site, in conditions involving hot acetone, even PTFE cannot be used for gaskets in tube heat exchangers.
It was explained in great detail; thanks for sharing, thumbs up!
It is better to use a PTFE gasket