The reason for the excessive pressure drop of the new energy vehicle detection is that the running system pipeline is not properly purged, especially in the newly installed system pipeline, many dirt (such as welding slag) enters the interior of the plate heat exchanger due to plate heat exchange. The cross-sectional area of the flow channel is narrow, and the sediment and suspended matter in the heat exchanger gather in the corner hole and the diversion zone, resulting in a large decrease in the flow channel area at this place, causing the main loss of pressure in this part. When the plate heat exchanger is selected, the area is too small, causing the flow velocity between the plates to be too high and the pressure drop to be too large. After the plate heat exchanger is operated for a period of time, the pressure drop caused by the surface fouling of the plate is too large, and the treatment method is to remove the heat transfer. The dirt or slabs in the flow path are fouled. For newly operated systems, clean them once a week according to the actual situation.
The new heating vehicle detection heating temperature can not meet the requirements. The reason is that the primary side medium flow is insufficient, resulting in large thermal side temperature difference, small pressure drop; cold side temperature is low, and cold and hot end temperature is low; multiple plate heat exchangers operating in parallel The flow distribution is uneven; the internal scale of the heat exchanger is severe. The treatment method is to increase the flow rate of the heat source or increase the diameter of the heat source medium pipeline, balance the flow rate of the multiple plate heat exchangers operated in parallel, and disassemble the surface of the plate heat exchanger to clean the surface of the plate.
The reason for the occurrence of string liquid in the detection of new energy vehicles is that the plate is corroded and cracked or perforated due to improper selection of the plate. The operating conditions do not meet the design requirements. The residual stress after cold stamping of the plate and the clamping size in the assembly are too small to cause stress corrosion. There is a slight leakage at the leakage groove of the plate, which causes harmful substances in the medium to concentrate and corrode the plate to form a string.
At this time, it is necessary to replace the cracked or perforated plate. In the field, the plate crack is found by the light transmission method, and the operating parameters are adjusted to meet the design conditions. The clamp size should meet the requirements when the heat exchanger is repaired and assembled, not the smaller the Well, the sheet material is reasonably matched.
The reason for the leakage of new energy vehicles is that the clamping dimensions are not in place, the dimensions are not uniform (the deviation of the dimensions should not exceed 3mm) or the clamping bolts are loose; some of the gaskets are out of the sealing groove, and the main sealing surface of the gasket has Dirty, damaged gasket or aging of the gasket; deformation of the plate, misalignment caused by the running pad; cracks in the sealing groove of the plate or in the two sealing areas. The fault is handled by re-clamping the equipment in the non-pressure state according to the clamping dimensions provided by the manufacturer. The dimensions should be uniform and the parallelism between the two compression plates should be kept within 2 mm. Mark the outer leakage part, then disassemble the heat exchanger one by one, reassemble or replace the gasket and the plate. Disassemble the heat exchanger, repair the plate deformation parts or replace the plate. When there is no spare part for the plate, the deformed plate can be temporarily removed and reassembled. When reassembling the disassembled panels, the panels should be cleaned to prevent dirt from adhering to the gasket sealing surfaces.
The new energy vehicle test is dedicated to the new energy vehicle battery test. Therefore, there is a certain requirement for the performance of Wuxi Guanya LNEYA new energy vehicle test. Any new energy vehicle test should be timely if any component encounters a fault. Solve, usually pay more attention to maintenance.