Brief introduction SPJ-6520 is mainly used as pretreatment filming agent before production in open-cycle cooling water system of steel, petrochemical, power, oil and other industries. It has good anti-corrosion effect in water pipes and heat exchanger, can be used as pretreatment filming agent for both cool and hot system. It can also be used as corrosion inhibitor during the normal operation. For better pre-film effect, the product is usually mixed use with SPJ-6521. SPJ-6520 is mainly composed by poly-phosphate compounds and additives. It is an ideal hybrid inhibitor. It can form a thin and dense anti-corrosion film on the metal surface and has the advantage of forming film fast, making up membrane well. In addition to corrosion, it has a threshold effect also. Reducing substances in cooling water won’t affect its inhibition and pre-film effect. It has the advance of safe operation and good compatibility also. Technical parameters Appearance Light yellow transparent liquid Odor No special odor Water soluble Easily pH (1%water solution) 6.0±1.0 Density (g/cm3, 20OC) 1.39±0.05 Usage SPJ-6520’s dosage is 350-450mg/L of the system water storage when use as pretreatment filming agent. When mix use with SPJ-6521, the ration between SPJ-6520 and SPJ-6521 is 3-5:1. The dosage is 20-50mg/L when the system in normal. Packing and storage The product is packed in 25L or 200L plastic drums, or packed according to customers’ requirements. It should be kept in cool, ventilated warehouses. Guaranty period: one year. The product is acid, so it can’t mix-use with strong alkaline, oxidizing, reducing substances. Users should wear personal protective equipment such as: rubber gloves, goggles, gas masks and chemical aprons when use the product. The product should be sealed when not in use.