The external leakage of plate heat exchanger (Lee and Hyde heat exchanger) is mainly manifested as leakage (a small number of discontinuous water droplets) and leakage (a large number of continuous water droplets). The main parts of external leakage are the seal between the plates, the leakage groove of the second seal of the plates, and the inner sides of the end plate and the compression plate.

There are four main reasons for the external leakage of plate heat exchanger: 1. The fastening size is not in place, the dimensions are uneven everywhere (the dimensional deviation should not be greater than 3mm) or the fastening bolts are loose. 2. The gasket part is separated from the sealing groove, the main sealing surface of the gasket has dirt, the gasket is damaged or the heat exchange sealing gasket is aging. 3. The deformation and assembly dislocation of the plate cause the running pad. 4. There are cracks in the sealing groove or the second sealing area of the plate.

Treatment of external leakage of plate heat exchanger: 1. In the pressureless state, re-clamp the equipment according to the clamping size provided by the manufacturer, the size should be uniform, the deviation of the clamping size should not be greater than 0.2n (mm) (n is the total number of plates), and the parallelism of the two clamping plates should be kept within 2mm. 2. Mark the leaking parts, then troubleshoot the heat exchangers one by one, and reassemble or replace the gaskets and plates. 3. Dismantle the heat exchanger and repair or replace the deformed plate. When the plate has no spare parts, the deformed plate can be temporarily removed and reassembled for use. 4. When reassembling the disassembled board, clean the board surface to prevent dust from adhering to the gasket sealing surface. (Lee and Hyde Heat Exchanger)