How is drying equipment anti-corrosion?

Drying equipment is one of the most commonly used equipment in chemical production, such as in the production of fertilizers, especially ammonium carbonate-based small nitrogen fertilizer production, centrifuges are one of the drying equipment is one of the most widely used unit equipment, can be considered, drying equipment has been used throughout the various sectors of national production. For drying equipment, can never simply think that it is only a thermophysical method of dehydration machinery. Due to the drying process to deal with different materials, different types of moisture content, the product indicators are different. Equipment installation sites are different, the manufacture of drying equipment for the selection of materials, equipment type and manufacturing, installation methods have different requirements. Correctly dealing with the above problems is one of the important factors for the successful design of drying equipment. The following introduces several kinds of anti-corrosion in the material and manufacturing some of the contents of the main points



1 phosphate a passivation process

In the vibrating fluidised bed dryer manufacturing, 70% of the parts are carbon steel layout. Process turnaround time is long, because of other features generate a lot of rust, paint before the need to use a lot of labour to remove rust. Phosphating a passivation chemical process, is to resolve the electrical and electrochemical response, resolved to deal with a one-time punishment, can make the rusty steel workpiece, the appearance of the original colour of the metal, at the same time in the metal appearance to generate a dense rust film layer, can be arranged in the humid atmosphere for more than a dozen days, but also will not corrode. Its operation is simple, can improve the working environment, can improve the working environment, reduce labour intensity, save manpower and material resources. To phosphating - passivation treatment and punishment solution contains emulsifier, molybdate, soluble molybdate, soluble phosphate and various acids, etc., the principle is not only used in the above models, don't similar layout or rack can accept this method of anti-corrosion treatment and punishment.



2 electrostatic powder coating in the drying configuration of the application of manufacturing

Traditional paints and coatings are liquid, which contains a large number of organic solvents such as fat ketone and hydrocarbons, to the birth, storage and transport, construction has brought a series of poor, flammable and explosive and is very unquiet. Because of certain toxicity, volatilisation to the atmosphere, the tension of pollution of the environment. Flash this, coating experts at home and abroad are committed to the development of new coatings with solution or without solution. One of such new coatings is powder coating. Vibrating fluidised bed dryer machine cover, mostly made of cold rolled stainless steel plate, and thus the cost is very high. Why use stainless steel and not accept ordinary carbon steel, because the configuration in the state of affairs will fight to a variety of corrosive materials and gases, and stainless steel corrosion resistance in addition to good performance, and therefore accept stainless steel cold-rolled plate made. With ordinary carbon steel held electrostatic spraying polyester resin powder coating, its anti-corrosion ability to complete and stainless steel comparable. Because the powder coating has a solid, long-lasting, decorative features, and has outstanding outdoor weathering and heat resistance, at the same time has outstanding resistance to corrosion and chalking performance, outstanding light and colour performance, so the electrostatic powder coating is completely practical in the dryer shell corrosion.



3 Austenitic nickel-chromium stainless steel welding exploration

 Drying configuration, there are many plate welding layout parts, most of the plate for 1Cr18Ni9Ti (18-8 type). Welding process often corrosion, fracture and other problems. Tension affects the life of goods and the use of performance. The difference between austenitic stainless steel and ordinary carbon steel lies in the poor thermal conductivity, large expansion coefficient when heated, and high resistance value. Because of these characteristics of austenitic steel, it is necessary to accept in addition to the welding process to welding. Intergranular corrosion is one of the intense problems of high alloy steel. This steel itself high corrosion resistance, but the welding process lowers the corrosion resistance. Austenitic steel welding corrosion situation: group, local, intergranular corrosion. A domestic factory introduced foreign drying configuration, bag filter stainless steel frame due to improper welding methods to destroy the structure of the material junction layout into the intergranular corrosion, drying process of the material contains acidic factors, the steel frame quickly caused by fracture.