1, the cause
① Run the system piping without normal purging, especially in the new installation system, many dirt (such as welding slag, etc.) into the plateheat exchangerinside, due to plateheat exchangerflow cross-sectional area is narrow, heat transfer The precipitates and suspended solids in the vessel accumulate at the corner holes and in the ducts, resulting in a significant reduction in the flow path area, resulting in a significant loss of pressure at this location.
② plateheat exchangerfirst selection when the area is too small, resulting in high flow rate between the board and the pressure drop is too large.
③ plateheat exchangerrunning for some time, due to surface friction caused by plate surface pressure is too large.
2, treatment methods
① removethe heat exchangerin the flow of dirt or plate scaling, for the new operation of the system, according to the actual situation once a week cleaning.When the surface cleaning scale (mainly CaCO3), the choice of containing 0.3 sulfamic acid solution or Containing 0.3 urolopine, 0.2 aniline, 0.1 potassium thiocyanate potassium nitrate solution as a cleaning solution, cleaning temperature 4O ~ 6O ℃. Do not disassemble equipment Chemical immersion cleaning, to open the heat exchanger cold medium into the export, or Install the equipment in the media inlet and outlet to install DN25 cleaning port, with a good cleaning solution into the device, soaked with water after cleaning the residual acid solution, so that pH ≥ 7. Open the cleaning, the plate in the cleaning Soak for 30min, then use a soft brush to clean the scale, and finally clean with water. Cleaning process should avoid damage to the plate and rubber pad.If you do not use mechanical anti-washing method, should be in advance in the media into the pipeline The equipment is connected with the mechanical cleaning truck, and the cleaning liquid is injected into the equipment in the opposite direction of the medium flow. The cleaning time is 10 ~ 15 min and the medium flow rate is controlled at 0.05 ~ 0.15m / s. And the concentration of Cl in water was controlled at 25 mg / I Next.
② the second cycle of water is best used after softening soft water, the general requirements of the concentration of suspended solids in the water is not greater than 5mg / L, impurity diameter of not more than 3mm, pH ≥ 7. When the water temperature is not greater than 95 ℃, Ca, Should not be greater than 2mmol / L; when the water temperature is greater than 95 ℃, Ca, Mg concentration should not be greater than 0.3mmol / L, dissolved oxygen concentration should not be greater than 0.1mg / L.
③ for the central heating system, you can use a way to the secondary replenishment.
Understand the plateheat exchanger pressure drop is too large reasons and the solution, you can reduce the use of plateheat exchanger trouble.https://www.forwon.com/