The inventory turnover rate (annual sales / average inventory) for angle steel in construction warehouses ranges from 4 to 6 times per year, depending on demand seasonality and specification popularity:
1) High-turnover specifications: Common grades/sizes like Q235B ∠50×5, ∠63×5, and ∠75×6 have a turnover rate of 6-8 times/year, as they are used in most construction projects (e.g., residential buildings, small workshops);
2) Low-turnover specifications: Specialized types like unequal-side ∠150×90×12 or high-strength Q355B ∠200×24 have a turnover rate of 2-3 times/year, as they are only used in large-scale projects (e.g., industrial plants, bridges);
3) Seasonal impact: Turnover rates peak in spring and autumn (construction peak seasons) at 0.6-0.8 times/quarter, and drop to 0.3-0.4 times/quarter in winter (cold regions) due to reduced construction activity. Warehouses optimize turnover by adjusting safety stock (10-15% of monthly demand for high-turnover items, 5-8% for low-turnover items).