Q: During on-site inspections, which parameter changes should be prioritized?
A: Daily inspections should focus on recording the inlet and outlet temperatures, flow rates, and differential pressures on both the hot and cold sides. If a sudden rise in differential pressure or a drop in temperature efficiency occurs, first check the filters and piping for blockages, then inspect the plate bundle for internal fouling. Filter blockage often manifests as increased inlet pressure with decreased flow, while piping blockage may cause localized differential pressure anomalies; after eliminating external factors, perform borescope inspection or disassembly of the plate bundle to confirm the degree of fouling.
A: The BRQ-200 uses an all-welded plate bundle structure without gaskets, so mechanical scraping should not be used during cleaning to avoid damaging the plate surface. Chemical cleaning is recommended based on the medium characteristics: water-side fouling can be cleaned with weak acid circulation, and oil-side deposits can be soaked with a dedicated cleaning agent followed by low-pressure flushing. After cleaning, thoroughly flush with clean water to avoid residual liquid corroding the plates. If fouling is severe and chemical cleaning is ineffective, contact the manufacturer to evaluate whether factory servicing is needed; on-site disassembly of the plate bundle is not recommended.
A: This model's applicable temperature range can be extended to below 400°C, with a design pressure not exceeding 4.0 MPa. O&M personnel should ensure that actual operating parameters do not exceed the nameplate rated values, and pay particular attention to avoiding excessively fast heating rates to prevent fatigue of the plate bundle caused by concentrated thermal stress. If the process requires temporary over-temperature operation, confirm with the designer in advance and increase monitoring frequency.
A: For long-term shutdown, drain the media from both sides and, if necessary, fill with dry nitrogen for protection to prevent corrosion of the inner plate surfaces. Before restarting, perform a low-pressure airtightness check, and after confirming there are no leaks, gradually increase pressure and temperature. For typical applications such as chilled water and cooling water heat exchange in HVAC systems, material heating or cooling in chemical processes, and liquid-liquid heat exchange in industrial waste heat recovery, it is recommended to note cleaning and inspection details in the shutdown maintenance records for future traceability.
