广东现货屋面镀铝锌彩钢板
彩涂卷预处理工艺
1、在进行彩涂卷线设计时,首先要考虑的三个基本要素为:质量、产品的多样化、高产，随着彩涂卷需求量的增加,对这三个要素的要求更加严格。影响涂层机组生产的因素很多,如带钢预处理、涂机和固化炉等,但最关键的两个因素是涂机和固化炉。预处理工艺的主要目的是除去带钢表面的油脂和杂质,并通过钝化,在钢板表面形成一层化学转化膜,以提高涂层与带钢基板间的附着力和带钢耐腐蚀能力。预处理工艺为:脱脂※刷洗※热水冲洗※表面调整※热水冲洗※钝化※烘干。
2、表面调整是生产某些产品时在磷酸盐或铬酸盐处理之前增加的一种表面处理工艺。使用含Ni、F离子的弱酸性药剂对带钢表面进行喷淋处理,其目的是提高涂层性能和涂敷型钝化剂的附着能力,并去除镀锌基板表面晶粒边界处析出的Al、Pb等物质,这种工艺尤其以日本的为代表。钝化通常需使用磷酸盐或铬酸盐对基板进行处理,钝化方法主要有喷淋型、浸入型和涂敷型。随着用户对涂膜均匀性要求越来越高和人们对环境保护的日益重视,涂敷型钝化方法倍受关注。涂敷型钝化采用辊涂法将处理液涂敷到带钢表面,形成金属与涂层之间的隔离膜。采用这种方法,钝化过程容易控制且膜厚均匀,同时废液很少或几乎没有,有利于环境保护。
3、在预处理工艺布置上有两种设计,一种是在入口活套前设预清洗段,活套后设预处理段,这种设计被欧洲的一些彩涂线供应商普遍采用,如法塔·亨特公司;另一种设计是只在活套后设预处理段,活套前不设预清洗段,这种设计为亚州的彩涂线供应商所采用,如新日铁公司和浦项公司。第一种设计优点是当原料表面质量不好时,设置在入口活套前的预脱脂处理段可将来料表面的大颗粒杂质处理掉,避免将大颗粒杂质带入活套,粘在活套的辊上,对后面的来料表面质量产生影响,缺点是消耗大、成本高;第二种设计是考虑完全能在预处理段将带钢表面处理干净,无需在活套前设预清洗段,增加运行成本。
Color coating preprocessing process
1. In the design of color coating rolling line, the first three basic elements should be considered are: quality, product diversification and high yield. With the increase of the demand for color coating rolling, the requirements for these three elements are more strict. There are many factors affecting the production of coating units, such as strip pretreatment, coating machine and curing furnace, but the two most critical factors are coating machine and curing furnace. The main purpose of the pretreatment process is to remove the grease and impurities on the surface of the strip steel, and to form a chemical conversion film on the surface of the steel plate through passivation to improve the adhesion between the coating and the strip substrate and the corrosion resistance of the strip steel. The pretreatment process is: defatasing scrub hot water washing surface adjust hot water flushing passivation drying.
2. Surface adjustment is a surface treatment process added in the production of some products before the phosphate or chromate treatment. The weak acid agent containing Ni and F ions is used to spray the strip surface, the purpose is to improve the coating performance and the attachment ability of the coated passivation agent, and remove Al, Pb and other substances precipitated at the grain boundary on the surface of the galvanized substrate. This process is especially represented by Japan. Passivation usually requires the use of phosphate or chromate to treat the substrate, and the passivation methods mainly include spray type, immersion type and coating type. With users 'increasing requirements for coating uniformity and people's increasing attention to environmental protection, coating type passivation methods have attracted much attention. The coating passivation applies the treatment solution to the surface of the strip steel to form a separation film between metal and coating. Using this method, the passivation process is easy to control and the film thickness is uniform, with little or no waste liquid, which is conducive to environmental protection.
3. There are two designs in the pretreatment process layout, one is pre-cleaning section before the entrance cover and pretreatment section after the cover. This design is widely adopted by some paint line suppliers in Europe, such as Fatah Hunter Company; the other design is only pre-cleaning section after the cover, which is adopted by paint line suppliers in Asia, such as Nippon Railway Company and POSCO Company. The advantage of the first design is that when the surface quality of the raw material is bad, the pre-skim treatment section set before the inlet sleeve can dispose of the large particle impurities into the surface and the influence on the surface quality of the incoming material with the high consumption and high cost; the second design is to increase the operation cost.
粤ICP备19012422号
