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This post was last edited by The one on 2026-7-17 08:15 🔣 If the plates of a plate heat exchanger suffer from \"deformation and warping\" (with a flatness deviation exceeding 0.2mm/m), can it still be used? And how can deformation of the plates be prevented? If the flatness deviation of the plate exceeds 0.15 mm/m, it can no longer be used! Deformation can lead to poor fit between the sealing surfaces, significantly increasing the risk of leakage; in severe cases, the plates may crack. Prevention requires \"controlling temperature and pressure + following standard operating procedures.\" Risks of continued use: ① The sealing surfaces cannot fit properly, resulting in a leakage rate of over 10 mL/h, which contaminates the medium (e.g., leakage in milk heat exchangers in food factories leads to the disposal of entire batches of products) ； ②The deformed plates are subjected to uneven stress, and they tend to crack when bolts are tightened (the cost of replacing a set of plates exceeds 20,000 yuan) ； ③The flow channels between the plates are uneven, resulting in excessively high local flow speeds that exacerbate scaling and wear. Reasons for deformation: ① Operating temperature exceeds the design value (for example, the designed temperature for a plate heat exchanger is 120°C, but the actual temperature exceeds 150°C; uneven thermal expansion and contraction of the plates cause warping) ； ②Sudden pressure increase (pressure rises from 0.5 MPa to 1.2 MPa in a short time, causing the plate to deform under the impact pressure) ； ③The bolt tightening torque is uneven (local torque exceeds the design value by 20%, causing deformation of the plates due to forced compression). Preventive measures: ① Strictly keep the operating temperature and pressure within the designed range; shut down the system immediately in case of overheating or overpressure ； ②Torque wrench for bolt tightening; tighten in diagonal stages, with a torque deviation of ≤5% per stage ； ③Thicker plates should be used (for example, replacing 0.8mm thick plates with 1.0mm thick ones increases the resistance to temperature and pressure by 30%). Example: In a certain project, the heat exchanger experienced plate deformation due to overheating; after replacing the plates and implementing proper temperature control, it operated continuously for 18 months without any further deformation issues.