Innovative Application of KY Double Screw Extruder in Powder Coating Processing Industry

The co-rotating double screw extruder, also known as the intermeshing co-rotating parallel double screw extruder, has the advantages of high conveying efficiency, strong dispersing and mixing ability, good self-cleaning performance, even distribution of residence time, and good adaptability. It is widely used in the modification of different plastics and rubber.

Key breakthroughs in KY double screw extruder technology

As a well-known manufacturer of parallel co-rotating double screw extruders, Nanjing KY has developed more than 500 types of material processes with its strong technical strength and advanced processing equipment. Expanding its market application domains is the direction and core competitiveness of KY's development. Currently, under the exploration of their technical personnel, KY parallel co-rotating double screw extruders have achieved technological innovation and application in the powder coating processing industry!

Powder coating is a solid synthetic resin coating composed of solid resins, pigments, fillers, and additives. Unlike ordinary solvent-based and water-based coatings, the dispersing medium of powder coating is not a solvent or water, but air. Its advantages include no solvent pollution, 100% film formation, low energy consumption, and easy storage and transportation.

How can double screw extruder technology be applied to powder coating processing?

There are two categories of powder coating: thermosetting and thermoplastic. The market is dominated by thermosetting powder coatings, which can be widely used in industries such as automotive, appliances, hardware, building materials, oil and gas pipelines, aerospace, and military.

China is the world's largest producer and consumer of powder coatings. According to statistics, in 2020, China's total production and sales of powder coatings were approximately 2.3 million tons, of which the sales of thermosetting powder coatings were approximately 2.12 million tons, a year-on-year increase of 10.4%, and the overall sales maintained a high growth rate. The production of powder coatings in China is mainly concentrated in the Yangtze River Delta, Pearl River Delta, and the Bohai Rim region. Among them, the Yangtze River Delta region has the highest proportion of powder coating production, averaging around 45% in the past five years. The production enterprises in the Yangtze River Delta mainly include Akzo Nobel, Huacai, Wenzhou Libang, Yushi, Changming, and other enterprises in Zhejiang Province; Huajia, Mejia, Sangrus, and other enterprises in Anhui Province; and Huaguang, Lao Hu, and other enterprises in Jiangsu Province.

The preparation process of powder coating is quite complicated. Special resins, color fillers, curing agents, and other additives are first pre-mixed in a mixer according to a certain proportion, and then melted, dispersed, and evenly distributed through the parallel co-rotating double screw extruder process, and finally extruded, pressed, crushed, and sieved to form powder coating. The key to determining the quality of powder coating lies in the dispersion and distribution effect of the parallel co-rotating double screw extruder during the process.

During this process, inorganic color fillers in the powder coating system are dispersed by the shearing force of the double screw in the section of mutual intermeshing, and the agglomerated particles are uniformly distributed in the base resin by the super surface renewal ability of the double screw, forming uniform islands to better ensure the excellent film formation, dispersibility, and leveling properties of the powder coating.