Glass-Lined Steel Tanks: What the Enamel Coating Really Delivers A glass lined steel tank is a bolted steel vessel whose interior is protected by vitreous enamel fused at 820-930°C, giving an inert, non-porous surface that resists corrosion for 30-50 years. The coating is verified at 0.25-0.45 mm and holiday-tested at 1500 V under AWWA D103-09 and ISO 28765. Engineered by Shijiazhuang Zhengzhong Technology Co., Ltd. (Center Enamel), these tanks serve water, wastewater, and