Overview
Sodium Silicate Bonded Casting Molding Sand represents an inorganic foundry material system where silica sand particles are bonded with sodium silicate (water glass). This technology gained prominence as an environmentally friendly alternative to phenolic urethane and other organic binder systems. The bonding occurs through a gelling reaction, typically accelerated by CO2 gas or ester hardeners. Compared to traditional systems, it produces fewer volatile organic compounds (VOCs) during casting, making it preferable for workplaces with stringent air quality regulations. The cured molds exhibit sufficient strength for most casting applications while maintaining good collapsibility after metal solidification.
Physical and Chemical Properties
The system's performance depends on both the silica sand characteristics and sodium silicate parameters. Standard grades use high-purity quartz sand with angular grain shapes for optimal binder distribution. The sodium silicate binder typically has a modulus (SiO2:Na2O ratio) of 2.0-2.5, balancing workability and final strength. Key advantages include thermal stability up to 1200°C and minimal gas formation during metal pouring, reducing casting defects. The binder undergoes dehydration at elevated temperatures, leaving a porous structure that minimizes veining defects. However, the system requires careful humidity control as excessive moisture can weaken bonds prematurely.
Main Applications
This material dominates in steel and ductile iron foundries for producing medium-to-large castings where organic binder residues could cause subsurface defects. Typical applications include pump housings, valve bodies, and heavy machinery components. The CO2-hardened variant is particularly popular for rapid core production in jobbing foundries. Recent developments see adoption in aluminum casting where its low gas generation benefits thin-walled parts. Some advanced versions incorporate additives like iron oxide or zircon flour for specialized applications requiring extreme thermal resistance or improved surface finish.
Safety and Storage
While safer than many organic alternatives, precautions remain necessary. The alkaline binder (pH ~11-12) requires PPE including gloves and eye protection during mixing. Dust control measures are critical when handling dry materials to prevent silicosis risks from airborne silica particles. Storage should maintain materials below 30°C with relative humidity under 60% to prevent premature binder activation. Bulk sand should be kept in silos with moisture barriers, while liquid sodium silicate requires sealed containers to prevent carbonation from atmospheric CO2. Shelf life typically exceeds 6 months when properly stored.
B2B Procurement Guide
Industrial buyers should specify multiple parameters: sand AFS grain fineness (typically 50-70), acid demand value (<5 ml), and binder viscosity (200-400 cP). For repetitive production, consider suppliers offering pre-mixed formulations with optimized additive packages. Quality verification should include bench life tests and retained strength measurements after humidity exposure. Many foundries now prefer regional suppliers to minimize transportation costs given the material's bulk density. For large-volume users, negotiated contracts with quarterly price adjustments help manage raw material volatility.
Related Manufacturers
- 主营：液体水玻璃、泡花碱、合成剂、工业液体花泡碱
- 主营：速凝剂、液体无碱速凝剂、硅酸钠、水玻璃、渗透结晶型防水涂料、防水剂dps、水性渗透无机防水剂、混凝土密封固化剂、混凝土养护剂、硅溶胶
- 主营：次氯酸钠、铝溶胶、乙二醇、水玻璃、甲基硅酸、三乙醇胺、二甲基亚砜、液体泡花碱、液碱、氢氧化钠、蒸馏水去离子水、二氯甲烷、软水盐、DMF、二甲基甲酰胺、聚乙二醇200、400、600、乙醇、甲酸、草酸、大苏打、冰醋酸、苯酚、氨水
- 主营：除油剂、乙酰氯、凡士林、水玻璃、硫酸铜、异丙醇、三乙胺、漂白粉、丙烯酸、硬脂酸、制冷剂、石油醚、清洗剂、铭酸酐、脱硝剂、二氯甲烷、涂料油墨、正丁酰氯、盐酸羟胺、印染助剂、四氢呋喃、环氧丙烷、偏硅酸钠、过硫酸钠、氢氧化钾、橡胶助剂
- 主营：三氟乙酸、三氟乙酸酐、亚硝酸钠、水玻璃、乙酸、氢氧化钠、柠檬酸、柠檬酸钠、苯甲酸钠、无水亚硫酸钠、三氯化铁、三氟乙酸乙酯
- 主营：高岭土、玻璃鳞片、轻钙、水玻璃、空心玻璃微珠、氢氧化铝、S95矿粉
- 主营：浇注料、膨润土、钠基膨润土、水玻璃、铸造膨润土、耐火水泥、钙基膨润土、打井泥浆土、硅酸钠溶液、石英砂、耐火砖、泡花碱、耐火骨料、耐火砂、除渣剂、铝矾土、铁水包浇注料、锅炉浇注料、耐火耐酸浇注料、耐高温浇注料、钢纤维浇注料、泥浆膨润土、钻井膨润土、耐火浇注料、膨润土厂家
- 主营：混凝土色差修复剂、灌浆料、无机渗透结晶防水剂、广西水玻璃、砂浆、聚合物、耐酸碱耐腐蚀砂浆、回弹王、道路修补砂浆、膨胀剂、破碎剂、增强剂、修补剂、渗透结晶母料、聚氨酯防水、益胶泥、固化剂、防水剂、防腐防水、脱模剂、自愈合无机渗透防水剂、修补料、固沙宝、水泥基、瓷砖胶、压浆料
- 主营：铝矾土、线圈胶泥、感应电炉炉衬、水玻璃、酸性炉衬材料、中性炉衬材料、捣打料、干振料、加热炉浇灌料、硅质打炉料、中间包可塑料、可塑快速修补料、石英砂、中频炉炉衬料、高岭土、透热炉打结料、橡胶颗粒、氢氧化钙、机制木炭、膨润土、绿泥白泥修补料、火山石板材、氧化钙、凹凸棒土粉、沸石粉沸石颗粒
- 主营：优氯净、甘氨酸、切削液、水玻璃生产厂家、水杨酸、硫酸锰、平平加、滑石粉、牛磺酸、白僵菌、磷酸铁、铵明矾、蛋白胨、碳酸镁、磷酸铝、戊二醛、纤维素、硫化钠、硫化钡、黄蜂蜡、硫化钙、氯化锌、氯化锰、氧化锑、氧化锆、氧化锌
- 主营：硫酸亚铁、聚丙烯酰胺、聚合氯化铝、水玻璃、石灰、活性炭、纯碱、片碱、次氯酸钠、漂白粉、醋酸钠、硫酸铝、焦亚硫酸钠、消泡剂、柠檬酸、葡萄糖
- 主营：蛋白胨、牛骨蛋白胨、福美钠、水玻璃、强氯精、单乙醇胺、三乙醇胺、氯化铜、防辐射硫酸钡
- 主营：造景彩色沙、儿童沙画台、园林景观鹅卵石、铸造石英砂、石英砂、地坪砂、金刚砂、水洗石、重钙粉、蛭石、玻璃砂、石英粉、陶瓷砂、复合岩片、火山石、珍珠岩、钢渣
- 主营：硅酸钠、硅酸钾、硅酸锂、水玻璃、注浆用水玻璃、泡花碱、混凝土固化剂、地坪抛光液、锂基固化剂
- 主营：普通石英砂、金刚砂、鹅卵石、水玻璃、重钙粉、云母、玻璃珠
- 主营：甲醛工业级、次氯酸钠、二氯甲烷、水玻璃、磷酸、冰醋酸、二甲基甲酰胺、片碱、液碱、蒸馏水、甲酸、苯酚、草酸、多聚甲醛、软水盐、硫酸铜、过碳酸钠、三氯乙烯、碳酸二甲酯、漂白粉、速溶硅酸钠、一水葡萄糖、无水乙醇、磷酸三钠、乙酸乙酯
- 主营：保险粉、硫酸铜、消毒液、水玻璃、杀菌剂、消毒剂、滑石粉、阻燃剂、加维粉、氯化镁、玉米葡、葡萄糖、硫酸锌、乳化剂、丙三醇、消毒水、漂白粉、防腐剂、酸亚铁、硫酸钙、自来水、氯化钙、填充剂、防霉剂、添加剂、麦芽糖