With the rapid development of modern industry, the usage of cooling water is increasing. However, long-term use in a large number of circulating exchange devices leads to the continuous formation of high-temperature oxide scales and silicon-containing oxide scales, as well as corrosion products, welding slag, and entrained sediment, grease coatings, pollutants, etc., generated during storage, transportation, and installation. The accumulation of dirt can reduce the cross-sectional area of the internal channels of the heat exchanger or even cause blockages, resulting in insufficient cooling water flow and reduced pressure, leading to downtime and production halts; it may even trigger safety accidents such as blistering, cracks, and pipe bursts.
The most commonly used cleaning methods for heat exchangers include physical cleaning, chemical cleaning, and manual cleaning.
1. Physical cleaning method: Common physical cleaning methods for heat exchangers yield good results for cleaning heat exchanger tube bundles with certain favorable hydraulic characteristics, but they are limited in their effectiveness for removing hard scales.
2. Chemical cleaning: It primarily relies on chemical agents to achieve the effect and purpose of removing scale and rust. Although the cleaning effect is better than that of physical methods, it can also cause certain corrosion to the heat exchanger's pipes, which is detrimental to the equipment's service life, and it can also pollute the environment.
3. Manual cleaning: High-pressure water jetting is used for cleaning heat exchanger tubes, which has a good removal effect on sludge inside the tubes, algae, bacteria, parasites, etc. on the surface. It not only has many advantages such as high cleaning efficiency, good cleaning quality, low cost, no damage to the cleaned objects, no pollution, easy to achieve mechanization, low labor intensity, safety, and reliability, but also practical experience has shown that after being cleaned by a high-pressure cleaning machine, the tube bundle achieves the effect of being restored to its original state.
4. Cleaning with a wire brush or a cutter head can break down the scale. Even for completely blocked pipes, the cutter head can clear them. This cleaning method primarily relies on physical cleaning, with the main unit providing power. The power is transmitted through a flexible shaft into the pipe, where the rotation of the shaft core drives the top brush and cutter head to rotate, thereby scrubbing away the dirt. At the same time, an inlet channel is designed on the flexible shaft to flush the dirt out from the inside to the outside. Due to the use of a flexible shaft, the elastic shaft can easily pass through bends such as U-shaped pipes.
Actually, no matter which method is used for cleaning the heat exchanger, it is essential to not only achieve the goal of cleaning the heat exchanger, but also take into account the safety of the operating personnel.
