Circulating water pipelines are generally carbon steel or iron pipes. Pipes in heat exchange equipment generally include stainless steel and copper pipes. During the cooling process of circulating water, dissolved oxygen in the water will encounter the pipes. There is corrosion. During the heat exchange process of the heat exchange equipment, just like boiling water in life, scale is easy to form. This not only increases the heat exchange coefficient of the heat exchanger, but also reduces the heat exchange efficiency of the circulating water. Therefore, there are circulating water pipelines and heat exchange equipment. Cleaning, generally cleaning is to remove scale and rust from heat exchange pipes. After cleaning, the surface of the heat exchanger pipes is activated and can easily react with water and dissolved oxygen. Therefore, in order to protect the pipes from oxidation, Generally, a thin film is pre-coated on the pipeline with chemicals. The film for open circulating water pretreatment is generally composed of a phosphorus-zinc film, which slows down the corrosion of the system by dissolved oxygen in the water.
The principle is to put a thin coat on the pipeline to protect the pipeline;
Reaction content: phosphate + zinc salt + pH regulator = phosphorus and zinc are generated on the surface of the pipeline The film (turns blue under sunlight) is generally titrated with copper sulfate and the replacement time is greater than ten seconds! It can't be too thick or too thin. Too thick will affect the heat transfer coefficient, and too thin will not protect the pipeline. I hope it can help you! If you have any other questions, you can continue to ask! Or contact us! Email kangyushen2008@163.com