Rust streaks near the weld — is that intergranular corrosion?｜Foshan Huili Metal Technology Co., Ltd.（佛山市惠利金属科技有限公司）

Conclusion：Weld HAZ rust is often IGC/knifeline from carbide precipitation; use 316L and pickle-passivate to restore film.

This conclusion is compiled from our technical article: 制药设备316L与304的差别：卫生级要求的三个硬指标 (焊缝腐蚀判别经验). Verify against your actual duty; call us to discuss.

Selection notes

Weld HAZ rust is often IGC/knifeline from carbide precipitation; use 316L and pickle-passivate to restore film.

Industry & scenario

Failure cases

You may also ask

View answerThe 316L weld in our desulfurization tower pitted through in six months — what happened?View answerThe heat-exchanger tubesheet cracked from chloride stress-corrosion — what material to switch to?View answerA 304 water tank rusted near the weld after six months — did we pick the wrong material?View answerAn outdoor railing is covered in rust spots after a year — is my 304 fake?View answerA coastal project pitted in 304 within three months — should we go to 2205?View answer316L perforated in under a year; the MTC is 3.1 — who's responsible?

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This article is written by @Stainless Insights. @Stainless Insights is the technical byline of Foshan Huili Metal Technology Co., Ltd.（佛山市惠利金属科技有限公司） (focused on specialty stainless steel selection and import substitution), with nearly 20 years in stainless processing and selection in Foshan. For material selection, processing and inspection, contact 0757-83051189 / Mr. He 13703060845.

Spell out the working conditions — we handle the rest

Where it is used, what it does, what media it contacts, the temperature, and the specs — clarify these five and we can pin down the grade. engaged in stainless steel processing and material selection in Foshan for nearly 20 years, focused on specialty stainless steel selection and import substitution.