Overview
Coil clay is a refractory material formulated to protect induction furnace coils from thermal shock, metal splash, and chemical corrosion. Composed primarily of high-alumina content with binders like silica sol or phosphates, it ensures electrical insulation while maintaining coil cooling efficiency. Developed as a critical consumable in steelmaking and non-ferrous metal production, modern coil clay formulations emphasize low water content (<6%) to prevent steam explosions during rapid heating. Leading manufacturers offer customized blends for specific furnace types and operating temperatures.
Physical and Chemical Properties
Industrial-grade coil clay exhibits bulk densities between 2.1-2.4 g/cm³ after curing, with cold crushing strength exceeding 15 MPa. Its thermal expansion coefficient (5.5-6.5 ×10⁻⁶/°C) matches common coil materials to prevent cracking. Chemically, the material contains 45-70% Al₂O₃ with SiO₂, MgO, and trace fluxes. Advanced versions incorporate silicon carbide (5-15%) for improved thermal conductivity. The pH typically ranges from 6-8 to prevent copper coil corrosion.
Main Applications
Primary use cases include lining induction furnace coils in steel mills (especially for stainless steel production) and foundries handling copper/aluminum alloys. The clay forms a protective shell that withstands temperatures up to 1650°C while allowing electromagnetic field penetration. Secondary applications include patching damaged ladle linings and sealing tundish joints. Some variants serve as backup insulation behind ceramic fiber modules in EAF sidewalls. Automotive and aerospace foundries prefer low-iron formulations (<0.5% Fe₂O₃) for critical casting operations.
Safety and Storage
Store in original moisture-proof packaging at <30% relative humidity. Opened containers should be resealed with plastic film to prevent premature curing. Shelf life is typically 6-12 months from manufacture. Workers must wear NIOSH-approved N95 masks during application due to fine particulate matter. The material becomes inert after firing but may release trace crystalline silica during removal - wet cleaning methods are recommended. Disposal follows local regulations for refractory waste.
B2B Procurement Guide
Key specifications to evaluate include: Al₂O₃ content (higher for ferrous metals), setting time (2-8 hours for most applications), and linear change after firing (±0.5% ideal). Request certified test reports for thermal conductivity (0.8-1.2 W/m·K at 1000°C). Bulk purchasing (20+ ton shipments) commonly attracts 8-15% discounts. Consider regional suppliers for reduced logistics costs - major producers cluster near steel hubs like Tangshan (China) and Pittsburgh (USA). Technical support for application methods (troweling vs. spraying) should be included in contracts.
Related Manufacturers
- 主营：抑尘剂、防腐涂料、密封固化剂、线圈绝缘胶泥、硅烷浸渍剂、混凝土养护剂、水泥基面增强剂、阻燃玻璃纤维布、玻璃纤维玻纤布
- 主营：润湿剂、消泡剂、脱模剂、脱氧剂、钢水净化剂、打炉料
- 主营：脱氧剂、精炼剂
- 主营：高铝耐火砖、浇注料、耐火砖、线圈胶泥、粘土耐火砖、异型耐火砖
- 主营：粘土砖、耐火材料、耐火浇注料、耐火骨料、高铝砖
- 主营：高铝砖、粘土砖、耐火球、耐火胶泥、浇注料、耐火泥、轻质保温砖、莫来石刚玉砖、氧化铝空心球砖、耐火砖
- 主营：高铝砖、刚玉砖、浇注料、线圈胶泥价格、耐火泥、耐火水泥、保温砖、粘土砖、陶瓷蓄热体、耐火球、陶瓷纤维产品、耐火材料、保温材料
- 主营：高岭土、铝矾土、高铝粉、线圈胶泥、炉衬料、石英砂、石英粉、长石粉、高铝砂、玻璃粉、电熔镁砂、锆英砂、金刚砂、矿渣粉、重晶石粉、彩砂、重金石、钙粉
- 主营：高铝砖、粘土砖、浇注料、耐火水泥、陶瓷蓄热体、蓄热球、耐酸砖、石棉绳、扇形砖、纤维纸、窑车砖、硅莫砖、莫来石砖、刚玉砖、喷涂料、捣打料、耐火砖
- 主营：轻质碳酸钙、4A沸石粉、膨润土、配重铁粉 铁砂、重晶石粉、氢氧化钙、红陶土 黄陶土、木粉、麦饭石粉、沸石粉、煅烧高岭土、水洗高岭土、滑石粉、负离子粉、硅藻土、白云石粉、玻璃鳞片、高铝耐火粉、蓝晶石粉
- 主营：火山石、石英砂、耐火泥、耐火胶泥、岩棉板、浇注料、黏土砖、耐火砖、钢包砖、高铝条砖、耐火浇注料、熔铝炉耐火材料、硅酸铝保温棉、耐火保温砖、莫来石保温砖、窑炉耐火砖、高铝耐火砖、sK-38耐火砖、高温粘合剂、钢纤维耐磨浇注料、自流防爆浇注料、高铝耐火球、珍珠岩、轻质保温砖
- 主营：麦饭石粉、滑石粉、沸石粉、线圈胶泥、氧化钙、膨润土、白云石粉、橡胶粉、石英粉、硅微粉、碳酸钙、石墨、硅藻土、抗菌粉、氢氧化钙、消石灰、陶土、活性白土、金刚砂、木粉、磁粉、海泡石粉、二氧化硅、高岭土、负离子粉
- 主营：生石灰氧化钙、熟石灰氢氧化钙、碳酸钙粉、滑石粉、膨润土、云母、云母岩片、珍珠岩、蛭石、玻璃粉、硅藻土、玻璃砂、陶瓷球、陶瓷砂、铝矾土、海泡石、木粉、木质纤维、电气石粉、锗石粉、橡胶颗粒、轮胎颗粒、石英砂、白云石
- 主营：碳酸钙、石英砂、金刚砂、滑石粉、矿粉、微硅粉、染色砂、陶瓷球、高岭土、鹅卵石
- 主营：耐火砖、耐火浇注料、耐火球、耐火胶泥、蓄热体、耐火水泥、耐火材料、耐热混凝土、高铝砖、刚玉砖
- 主营：耐火浇注料、酸性炉衬材料、高效除渣剂、线圈胶泥、铝矾土高铝细粉、石墨化增碳剂、透热炉打结料、中性炉衬材料、导电粉、中间包可塑料、打炉料、干振料、刚玉炉衬料、硅藻土、电气石托玛琳粉、膨润土、重晶石硫酸钡粉、蛭石、高岭土、橡胶颗粒粉、石英沙石英粉、绿泥白泥修补料、凹凸棒土、重质轻质碳酸钙、雨花石炉料