【Haichuan Anti-Corrosion Knowledge】Poor implementation of key construction techniques can reduce the industrial anti-corrosion lifespan by 10 times! !

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This post was last edited by HaiChuanLaoYu on 2026-4-28 21:04. Inadequate key construction techniques result in an industrial anti-corrosion lifespan that is 10 times shorter! ! With the same equipment, the same paint, and the same environment, while others can use it for 10 years, it will rust through after just 1 year. Do you think it’s due to poor quality materials? Is it bad luck? Is the environment too harsh? All wrong. 90% of cases of corrosion-related rework, paint peeling, rusting, and leakage stem from the same step: surface preparation. Today, I’ll clearly explain this truth that has been known in the industry for decades: the corrosion resistance lasts 10 times longer; the difference doesn’t lie in the paint, but in rust removal. If this step is done correctly, it won’t rust for 10 years ； If done wrong, it will be scrapped after one year. I. The most painful truth: the paint determines the upper limit, while rust removal determines the lifespan. No matter how good the fluorocarbon coating is, no matter what the zinc content is, and no matter how expensive the imported paint is, if rust isn’t completely removed, it’s all pointless. The base surface isn’t good; the coating is just a layer \"pasted on top of the rust\", and it peels off easily when exposed to sunlight, moisture, or freezing temperatures. II. The key step in determining the corrosion resistance life: sandblasting for rust removal to Sa2.5 standard. This is not an optional step – it is essential. What does Sa2.5 grade mean? Industry standard in one sentence: The metal surface should be white and shiny, free of oxide scale, loose rust, oil stains, and residual old paint. Upon touch, it is clean, slightly rough, has a textured surface, and can hold paint. It’s not possible to achieve this: the adhesion quality is completely ruined; no matter how high the salt spray level is, it doesn’t make any difference. Rusting occurs within a year, and the material fails after two years. It fails the acceptance tests outright. Thirdly, why can the lifespan differ by 10 times? (At a glance) 1) Sa2.5 sandblasted coating: provides good adhesion, is waterproof and resistant to salt spray; lifespan: 8–15 years. 2) Rough grinding/manual rust removal: rust, oil, and old paint remain; the coating remains on the surface only; lifespan: 0.5–2 years. Difference: 10 times! IV. 3 major rust-removal mistakes that 90% of construction sites make: 1) Using \"manual grinding\" in place of \"sandblasting\" to save costs, time, and equipment – resulting in paint peeling off within half a year. 2) Inadequate sandblasting leaves black spots, old paint, and oxide layers; it may seem clean, but it doesn’t meet the standards, with an 80% rust recurrence rate within a year. 3) Failing to apply paint promptly after sandblasting; covering rust with more paint is like putting a blanket over it, which only speeds up further deterioration. V. 3 ironclad rules that experienced workers never share (follow them for stable results for 10 years): 1) Sandblasting must reach Sa2.5 level – work cannot start if this standard isn’t met; this is a minimum requirement, not just a suggestion. 2) The primer must be applied within 4 hours after sandblasting; if too much time passes, any effort to prevent rust will be in vain. 3) The surface must be free of oil, water, and dust. Oil is the number one enemy of coatings; even a single drop can cause damage to the coating. VI. A harsh truth in the industry (everyone knows it, but few dare to say it): In anti-corrosion projects, 70% depends on rust removal, and 30% depends on the paint used. The paint is too expensive; it’s a waste of money ； Poor rust removal is just a waste of money. If you are a purchasing officer, project manager, construction team leader, or boss, remember this: if rust removal is not up to standard, all anti-corrosion measures will be pointless. Make one right move, and double your lifespan ； One wrong step, and an entire year goes to waste. By 2026, the inspection standards will become stricter and penalties more severe; don’t fail at the most critical stage again.