大型储罐防腐蚀质量控制

Anti-corrosion quality control of large storage tanks

大型储罐防腐蚀质量控制的好坏与以下几个因素有关:(1)涂料的控制。根据使用温度和环境要求选用涂料;(2)防腐蚀的过程控制。底漆涂装时间间隔宜控制在2～4 h、重涂涂层的最大时间间隔宜为2～7 d,控制涂料配置的熟化时间和使用期限;(3)涂装的温度与湿度控制。可涂装的环境温度为5～35℃,湿度不宜大于80%;(4)检测指标的控制。表面粗糙度宜控制在40～75μm。表面可溶性氯化物不超过5μg/cm2,罐内介质浸润区域不超过3μg/cm2。漆膜厚度控制应根据设计文件规定的内容实施。绝缘型涂层表面电阻率应不超过1013Ω、导电型涂层控制在108～1011Ω、绝缘层不允许存在孔隙,导电涂层的孔隙不应超过2个/m2。

The anti-corrosion quality of large storage tanks are affected by the following factors ： 1. Coating control. The coating shall be selected based upon the service temperature and environmental requirements; 2. Anti-corrosion process control. The time interval between coating applications shall be controlled at 2 - 4 hours, the maximum time interval between re-coated coating is 2-7 days, and the curing time and service life of coatings shall be controlled; 3. Control of temperature and humidity of coating application, the proper ambient temperature for coating application is 5 - 35 ℃, the humidity shall be no higher than 80% ; 4. The control of testing indexes. The surface roughness shall be controlled between 40 - 75 p,m, the soluble chlorides in in-tank medium-soaked area shall not be higher than 3μg/cm^2 and 5μg/cm^2 for other area; The film thickness should be controlled based upon the requirements in the design document. The resistivity of insulation coating should be no less than 1013 ohm, and that of conductive coating should be controlled between 10^8 ohm and 10^11 ohm. No pores are allowed for insulation layer, and the porosity of the conductive coating should be no more than 2 per square meter.