【概 述】
铝酸钙生产方法是按比例将铝土矿和石灰石破碎后成球，送入回转窑，在1300℃锻烧冷却后粉碎包装即为铝酸钙产品，铝酸钙产品分水处理用、炼钢除渣剂、高铝水泥三大类。
凡以铝酸钙为主，氧化铝含量约50％的熟料，磨制的水硬性胶凝材料，称为高铝 水泥。
【理化指标】
高铝水泥用铝酸钙执行标准为：《中华人民共和国标准（GB201-2000）》。
SiO2≤10％，Fe2O3≤3％。
【产品分类】
高铝水泥的标号系按本标准规定的强度检验方法测得的3天抗压强度表示，分为425、525、625和725四个标号。
【包 装】
水泥袋装时应采用防潮纸袋（四层普通包装纸，三层防潮纸），每袋净重50±1公斤。如水泥生产单位与购货单位双方同意，可以改变包装方式。纸袋上须清楚标明工厂名称、水泥的名称、标号、重量和包装日期及编号。其他包装时也须标有相同内容的标志，或附有相同内容的卡片。
注：包装纸袋应符合JG59－63《水泥包装用纸袋》标准。
【用 途】
（1）配制不定形耐火材料。
（2）配制石膏矾土膨胀水泥、自应力水泥等特殊用途的水泥。
（3）抢建、抢修、抗硫酸盐侵蚀和冬季施工等特殊需要的工程。
【注意事项】
1．在施工过程中：一般不得与硅酸盐水泥、石灰等能析出氢氧化钙的胶凝物质混合，使用前拌和设备等必须冲洗干净。
2．不得用于接触大碱性溶液的工程。
3．高铝水泥水化热集中于早期释放，从硬化开始应立即浇水养护。一般不宜浇注大体积混凝土。
4．高铝水泥混凝土后期强度下降较大，应按最低稳定设计。高铝水泥混凝土最低稳定强度值以试体脱模后放入50±2℃水中养护，取龄期为7天和14天强度值之低者来确定。采用标号525号以上的水泥、小于0.40的水灰比和400公斤／米3以上的水泥用量时，即可配出最低稳定强度200公斤／厘米3以上的混凝土。
5．若用蒸汽养护加速混凝土硬化时，养护温度不高于50℃。
6．用于钢筋混凝土时，钢筋保护层的厚度不得小3厘米。
7．未经试验，不得加入任何外加物。
8．不得与未硬化的硅酸盐水泥混凝土接触使用；可以与具有脱模强度的硅酸盐水泥混凝土接触使用，但接茬处不应长期处于潮湿状态。
High alumina refractory cement, refractory cement，silicate cement
Aluminate cement (high alumina cement, also known as the original refractory cement) is used in the configuration of unshaped refractory, expansive cement, self-stressing cement and chemical building materials, etc. for special needs such as winter construction project.
Standard: GB201-2000
Cement Type: CA-50-5 type, 6, 7, and 8
Chemical Composition (%):
Al2O3 | SiO2 | Fe2O3 | R2O |
≥50,＜60 | ≤8.0 | ≤2.5 | ≤0.40 |
Fineness: Specific surface area is not less than 300m2/mg, as the agreement made by both sides.
Setting time: Initial setting time is not earlier than 30min and the final setting time not later than 6h.
Strength: The strength of every age value shall not be less than the value of the following table.
Compressive Strength (Mpa) Bending Strength (Mpa)
6h | 1d | 3d | 6h | 1d | 3d |
20 | 40 | 50 | 3.0 | 5.5 | 6.5 |
The net weight of bagged cement is 50Kg, and shall not be less than 98% of marked weight. The total mass of 20 random bags should not be less than 1000Kg. The packaging can be changed by consultation. Special attention should be paid to moisture protection and not mixed with other varieties of cement in the transport and storage, stored period not exceeding for three months and expired or damp clotting, should be re-tested before being used.
1) During the construction, do not mix it with aluminate cement and lime that has hydroxide the cementitious material, and before using the mixing equipments must be washed clean.
2) Do not be used in alkaline solution engineering.
3) It should be immediately watered for conservation from the beginning of hardening.
4) The concrete curing temperature shall not exceed 50 ℃ when accelerating the hardening of refractory cement.
5) When used for steel reinforced concrete, the protective layer thickness should not be less than 60mm.
6) Do not add any external material if not tested.
7) Do not contact with any non-hardening Portland cement.
