What are the advantages of spraying ETFE anti-corrosion coating on the head
Information summary:The advantages of ETFE (ethylene tetrafluoroethylene copolymer) anti-corrosion coating sprayed on the head can be explored from multiple dimensions such as material properties, protective performance, and process adaptability. It is widely used in fields such as chemical engineering, environmental protection, and energy due to its excellent comprehensive performance. Here is a specific analysis:
The advantages of ETFE (ethylene tetrafluoroethylene copolymer) anti-corrosion coating sprayed on the head can be explored from multiple dimensions such as material properties, protective performance, and process adaptability. It is widely used in fields such as chemical engineering, environmental protection, and energy due to its excellent comprehensive performance. Here is a specific analysis:
1、 The anti-corrosion advantages brought by the intrinsic characteristics of materials
1. Extreme corrosion resistance
ETFE coating has almost "zero penetration" resistance to strong acids (such as sulfuric acid, nitric acid), strong bases (such as sodium hydroxide), salt solutions, and organic solvents (such as benzene, carbon tetrachloride). For example, in a 98% concentrated sulfuric acid environment, ETFE coatings can withstand high temperatures of 150 ℃ for a long time without degradation, while traditional epoxy resin coatings experience swelling and damage above 80 ℃.
Typical scenario: After spraying ETFE on the head of a chemical reaction vessel, it can simultaneously resist the dual corrosion of chlorine gas and hydrochloric acid mist, and its service life is extended from 2-3 years for ordinary coatings to more than 10 years.
2. Weather resistance and aging resistance performance
The ETFE coating has a UV aging resistance level of ASTM G154-05 standard level 8. In outdoor or strong UV environments (such as photovoltaic equipment heads), the glossiness attenuation is less than 5% within 10 years, while the polyvinyl chloride (PVC) coating shows powdering and cracking after 5 years.
2、 Physical performance optimization and user experience
1. High wear resistance and impact resistance
The Shore hardness of ETFE coating reaches D65-70, with a wear resistance of only 0.01g/1000 times (Taber wear test), making it suitable for flushing media containing solid particles (such as slurry and powder conveying equipment). For example, after spraying ETFE on the mortar tank head used in mines, the wear amount is reduced by 80% compared to uncoated heads, and the maintenance cycle is extended from 6 months to 3 years.
2. Low friction coefficient and self-cleaning properties
The surface friction coefficient of ETFE is only 0.05-0.1 (better than 0.08 for PTFE), making it difficult for dust and viscous liquids (such as syrup and ink) to adhere. For example, after spraying ETFE on the head of food processing equipment, the amount of cleaning water used is reduced by 40%, and no chemical cleaning agents are required, which meets the FDA food contact material standard (21 CFR 177.1350).
3、 Temperature adaptability and safety characteristics
1. Stability within a wide temperature range
ETFE coating can maintain stable performance in the temperature range of -200 ℃ to 150 ℃:
Low temperature scenario: After spraying ETFE on the head of a liquefied natural gas (LNG) storage tank, it maintains flexibility in an environment of -162 ℃ to avoid corrosion penetration caused by coating brittleness;
High temperature scenario: In a steam environment of 120 ℃, the ETFE coating maintains a tensile strength retention rate of over 90% for chemical heat exchanger heads, while the fluororubber coating can only maintain 60%.
2. Flame retardant and low toxicity
The oxygen index (LOI) of ETFE reaches 29% (higher than the flame retardant standard of 26%), and only decomposes a small amount of non-toxic gas (mainly hydrogen fluoride, with a concentration below the danger threshold) when exposed to fire, making it suitable for scenarios with high fire safety requirements (such as pharmaceutical workshops).
4、 Process and construction advantages
1. Coating uniformity and adhesion
Through electrostatic spraying or hot melt sintering processes, ETFE coating can form a uniform film layer of 0.5-2mm on complex curved surfaces of the head (such as elliptical and butterfly heads), with an adhesion force of 50N/cm (ASTM D3359 standard), far higher than the 5-10N/cm of ordinary paint. For example, the fluidized bed impregnation method is used to spray ETFE on the head of large pressure vessels, which can eliminate weak points in the coating at welds, corners, and other parts.
2. Construction efficiency and maintenance costs
Single spraying can form the product without the need for multiple layers of coating, and the construction period is 50% shorter than traditional anti-corrosion methods such as lining glue; If there is local damage, it can be repaired with hot melt patches without the need for overall rework. According to statistics from a certain chemical enterprise, the full lifecycle maintenance cost of ETFE coated heads is 60% lower than that of lead lined heads.