The compressor interstage cooling section has clear control requirements for heat exchanger outlet temperature and pressure drop. Typically, investigation is required when the outlet temperature deviation exceeds 5°C or the pressure drop increases by 15%. The HX-55 plate-fin heat exchanger handles heat exchange tasks in this scenario, and on-site O&M personnel need to focus on the following key points.
Key point 1: Record inlet and outlet temperature, pressure, and flow rate every shift, and establish a trend file. Recorded data should include stable readings under the same operating conditions, avoiding periods of load fluctuation. The trend file can be used to identify gradual changes in heat exchange performance, such as a progressive increase in outlet temperature and pressure drop, which often indicates fouling in fin channels or uneven airflow distribution.
Key point 2: Pay attention to the temperature rise issue in compressor interstage cooling. O&M personnel often find that the heat exchanger outlet temperature rises with operating time, accompanied by a simultaneous increase in pressure drop. In this case, first check whether the cooling medium flow rate and inlet temperature deviate from design values, then check whether the fin channels are blocked. Recorded data can serve as a basis for subsequent fine-tuning of channel arrangement, but before adjustment, confirm that measurement point locations and instrument accuracy are consistent to avoid misjudgment.
Key point 3: During maintenance, focus on inspecting fin channels and sealing structures. Plate-fin heat exchanger channels are narrow, making cleaning difficult after fouling. It is recommended to schedule cleaning cycles based on pressure drop trends. Aging seals may cause media cross-contamination, so interfaces and welds need regular inspection.
Key point 4: Selection and operation must match operating conditions. The HX-55 plate-fin heat exchanger is suitable for medium-low pressure and clean media applications. If the cooling medium contains particulate matter or is prone to scaling, filtration or pretreatment measures should be installed upstream. Avoid overtemperature and overpressure during operation, and ensure design parameters retain margin.
In on-site O&M, data recording and trend analysis are the basis for judging heat exchanger condition. Combined with instrument calibration and channel inspection, they can reduce unplanned downtime.
