After operating for a period of time under conditions approaching 200°C, some detachable plate heat exchangers develop port leakage or abnormal pressure drop. Upon disassembly and inspection, the sealing gaskets are often found to have aged, swelled, or even cracked. This phenomenon reminds design and selection engineers that the sealing structure of a heat exchanger is closely related to temperature boundaries.
The structural feature of the BXS-55 brazed stainless steel heat exchanger is that the plates form an integral seal through brazing, without using detachable gaskets. Its applicable temperature range is -40°C to 200°C, and its design pressure is 3.0MPa. Compared with detachable plate heat exchangers with gaskets, this product has no leakage path caused by gasket aging or swelling. Daily maintenance mainly consists of external cleaning and inspection of operating parameters, with no need for regular disassembly and replacement of seals. For occasions with frequent temperature fluctuations and where frequent shutdowns for inspection are inconvenient, this structural difference is worth considering during the selection stage.
A design pressure of 3.0MPa does not mean that it can operate under limit parameters for a long time. It is recommended to reserve a margin of more than 10% in actual operation, covering both pressure and temperature. If operating under conditions approaching 200°C for a long time, inlet and outlet temperature and pressure data should be recorded regularly as a basis for judging the condition of the internal flow channels. When the pressure drop continues to rise while the flow rate does not change significantly, it often indicates that scaling or blockage may exist in the flow channels, and cleaning should be arranged according to the characteristics of the medium.
From the perspective of maintenance methods, detachable plate heat exchangers require regular disassembly and replacement of seals, while the maintenance focus of the BXS-55 brazed stainless steel heat exchanger shifts to external cleaning and trend management of operating parameters. During selection, sealing method, temperature and pressure margin, and medium cleanliness can be evaluated side by side, and then the solution can be determined in combination with shutdown maintenance conditions.
