Views: 0 Author: Site Editor Publish Time: 2025-08-08 Origin: Site
Stainless steel pipes are widely used due to their corrosion resistance and easy maintenance. However, after long-term use, their surfaces may accumulate stains such as oil, scale, and rust, which not only affect the appearance but also may reduce their corrosion resistance. Scientific cleaning methods can effectively remove stains and protect the surface passivation film, extending the service life of the pipes. When cleaning, it is necessary to select appropriate tools and reagents according to the type of stain, the surface state of the pipe (mirror, matte, brushed), and the application scenario (food-grade, industrial-grade).
The core of daily cleaning is to promptly remove surface dust and mild stains to avoid difficulty in handling after long-term accumulation. For smooth surfaces (such as mirror stainless steel pipes), first, use a soft microfiber cloth dipped in clean water to wipe and remove surface dust; if there is a small amount of oil, add a neutral detergent (such as dish soap, with a concentration of 0.5-1%) to clean water, gently wipe, then rinse with clean water, and finally dry the water with a dry cloth to prevent water marks from remaining. For brushed or matte surfaces, it is necessary to pay attention to keeping the wiping direction consistent with the texture. Avoid using hard brushes or steel wool to prevent scratching the surface and forming scratches. For example, the stainless steel pipes of kitchen exhaust ducts can be wiped with a warm water-dampened cloth once a week to remove the initial oil stains attached to the oil fume, reducing the difficulty of cleaning heavy stains later. For stainless steel pipes exposed outdoors (such as guardrails, billboard brackets), basic cleaning should be carried out once a month to remove surface attachments such as dust and bird droppings, preventing the formation of stubborn stains after rain washing.
Oil Stain Treatment: Alkaline cleaners can be used to treat oil stains on the outer walls of industrial pipelines and oil fume stains on kitchen pipelines. Mix baking soda and water in a ratio of 1:3 to make a paste, evenly apply it to the oil-stained area, let it stand for 10-15 minutes, then wipe with a damp cloth; for heavy oil stains, use a special stainless steel cleaner (containing surfactants), spray it, wait for 5 minutes, then wipe with a non-abrasive sponge, and finally rinse with clean water. Note: Food-contact stainless steel pipes (such as water dispenser pipes) need to use food-grade cleaners. After cleaning, rinse with boiling water 2-3 times to avoid chemical residues.
Scale Removal: The inner or outer walls of stainless steel pipes used for hot water transportation are prone to scale formation (mainly composed of calcium carbonate). For external wall scale, spray white vinegar (or citric acid solution, with a concentration of 5-10%) on the surface, let it stand for 20 minutes, then wipe with a cloth; for inner wall scale, it can be treated by cyclic flushing. Add the citric acid solution to water in a ratio of 1:50, pass it into the pipe, soak for 30 minutes, then rinse with clean water until there is no sour taste. For example, the stainless steel pipes of solar water heaters can be descaled once every 3-6 months to improve heat conduction efficiency.
Rust and Spot Treatment: Most of the rust on the surface of stainless steel pipes is "floating rust" (formed by the oxidation of attached iron filings or iron ions in the environment), not the rust of the pipe itself. Apply a 10% nitric acid solution or a special stainless steel rust remover to the rusted area, let it stand for 3-5 minutes, then wipe with a cloth and rinse with clean water; if the rust is shallow, you can also apply toothpaste (containing fine abrasive particles) and wipe in a circular motion with a soft cloth to remove rust spots by grinding. After treatment, dry with a dry cloth and apply a small amount of olive oil (edible vegetable oil for food-grade scenarios) to form a protective film.
Sanitary Pipes (Food, Pharmaceutical Fields): Such pipes (such as pharmaceutical water pipes, milk delivery pipes) not only need to remove stains but also need to meet sterility requirements. The cleaning process includes: first, rinse the inner wall with purified water for 3-5 minutes to remove residual media; then circulate and clean with a 2-3% sodium hydroxide solution for 30 minutes (temperature controlled at 60-80℃) to remove organic stains; then circulate and disinfect with a 1-2% nitric acid solution for 20 minutes to kill microorganisms; finally, rinse with injection water until neutral (pH 6.5-7.5). After cleaning, endotoxin testing (≤0.25EU/ml) and microbial limit testing (≤10CFU/100ml) are required.
Industrial Pipes (Chemical, Energy Fields): Industrial stainless steel pipes often come into contact with corrosive media. When cleaning, avoid using reagents that may react with residual media. For example, for pipes transporting acidic media, rinse the residual acid with clean water first, then neutralize with a weakly alkaline solution (such as sodium carbonate solution); for paint and coating attachments on the outer wall, first spray a paint remover (keep away from fire sources), wait for the coating to soften, peel off with a plastic scraper, then wipe with a neutral cleaner. After cleaning, industrial pipes need to undergo pressure testing to ensure no leakage.
Recommended Tools: Microfiber cloths, sponges (non-steel wire surface), soft brushes (nylon material), plastic scrapers (for removing hard attachments).
Forbidden Tools: Hard tools such as steel wool, sandpaper, and metal scrapers, to avoid scratching the surface and damaging the passivation film; chlorine-containing cleaners (such as 84 disinfectant), strong acids (hydrochloric acid, sulfuric acid), etc., which may cause pipe corrosion or intergranular corrosion.
For example, after cleaning stainless steel pipes with steel wool, fine scratches will appear on the surface. These scratches are prone to accumulate stains and become corrosion starting points, reducing the corrosion resistance of the pipes. In addition, after cleaning, ensure the surface is completely dry, especially in humid environments, as residual moisture may accelerate local corrosion.
Regularly (every 3-6 months) passivate the surface of stainless steel pipes. Wipe the surface with a 5-10% nitric acid solution, let it stand for 10 minutes, then rinse with clean water. This can repair the damaged passivation film and enhance corrosion resistance.
Outdoor stainless steel pipes can be coated with a thin layer of anti-rust oil (for non-food-grade scenarios) to form a physical barrier against atmospheric corrosion.
Avoid direct contact between stainless steel pipes and carbon steel (such as placing a rubber pad when fixing with carbon steel brackets) to prevent galvanic corrosion.
Through scientific cleaning and maintenance, the service life of stainless steel pipes can be extended by 5-10 years, while maintaining good appearance and performance, ensuring stable application in various fields.
