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SPCC/SPCD/SPCE/SPCG galvanized pipes (cold-rolled galvanized steel pipes compliant with JIS G3141, with graded formability) are widely used in machinery manufacturing for non-high-load fluid conveying pipes (e.g., equipment cooling water pipes) and protective sleeves—SPCC for basic applications, SPCD/SPCE for bendable parts, SPCG for high-precision fittings; applied in home appliance sector for internal water/air circulation pipes of washing machines and air conditioners; used in furniture manufacturing for metal cabinet support tubes and adjustable shelf pillars, leveraging corrosion resistance and easy shaping; adopted in light industry for small-scale compressed air pipes and liquid transport lines in daily chemical equipment; and applied in electronic equipment for chassis support tubes and internal wiring protection pipes, with specific grades selected based on forming complexity, surface finish and precision needs.