With the development of industry, plate heat exchanger has been widely used in the fields of food, machinery, metallurgy, petrochemicals and ships, and has become the leading heat exchanger in urban central heating engineering. In case of equipment failure, how can we solve it? Today Haiyuan will briefly introduce the following to you:
I. faults often encountered in the use of plate heat exchanger
1. Leakage mainly includes leakage (small amount, discontinuous water drop) and leakage (large amount, continuous water drop). The main parts of the leakage are the seal between the plate and the plate, the two-way seal leakage groove of the plate and the inner side of the end plate and the compression plate.
2. The main feature of heating temperature not meeting the requirements is that the outlet temperature is too low to meet the design requirements.
3. The pressure drop is large, the pressure drop of medium inlet and outlet exceeds the design requirements, even many times higher than the design value, which seriously affects the system's requirements for flow and temperature. In the heating system, if the pressure drop on the hot side is too large, the primary side flow will be seriously insufficient, that is, the heat source is not enough, resulting in the secondary side temperature can not meet the requirements.
II. Causes of faults and Solutions
1. In case of leakage without pressure, re clamp the equipment according to the clamping size provided by the manufacturer, the size shall be uniform, and the deviation of the clamping size shall not be greater than ± 0.2N (mm) (n). Is the total number of plates), and the parallelism between the two pressing plates shall be kept within 2 mm. Mark the leaking parts, disassemble the heat exchanger one by one, and reassemble or replace the gasket and plate. Disassemble the heat exchanger, repair or replace the deformed part of the plate. In the absence of spare parts, the deformed parts can be temporarily removed and reassembled for use. When reassembling the disassembled plate, clean the plate surface to prevent dirt from adhering to the gasket sealing surface.
2. If the pressure drop is too large, remove the dirt or plate scale in the flow passage of the heat exchanger. For the newly operated system, clean it once a week according to the actual situation. During cleaning, avoid damaging the plate and rubber pad. If the mechanical backwashing method is not disassembled, a pipe orifice shall be connected on the medium inlet and outlet pipelines in advance, the equipment shall be connected with the mechanical cleaning truck, and the cleaning liquid shall be injected into the equipment in the opposite direction of the medium flow. The circulating cleaning time shall be 10-15 min, and the medium flow rate shall be controlled within 0.05-0.15 M / s.
3. If the heating temperature cannot meet the requirements, increase the flow of the heat source or increase the diameter of the medium pipeline of the heat source. Balance the flow of multiple plate heat exchangers in parallel operation. Disassemble the plate heat exchanger to clean the scale on the plate surface.