Overview of the current situation and development of basket grinders

0 Introduction
the process of coating production is to mix pigment solid particles into the liquid coating, so that it forms a uniform fine suspension dispersion. The original particles of the pigment are very small, their particle size is about 0.01 to 2 m, because the raw particles in the process of processing and storage, often glued to each other into the aggregate (secondary particles), its particle size may increase to more than 100 m, so in the paint manufacturing needs to remove the aggregate aggregation, and stable and uniform dispersion in the coating. In the production process of coatings, the selected grinding dispersion equipment plays a very important role in the dispersion of pigments in coatings, the best pigment performance (coloring force, covering force, weather resistance, etc.), and the resulting performance of coatings and coatingsTherefore, how to improve the dispersion effect in coating production, the development and use of high-efficiency dispersion equipment, as well as the selection of high-quality raw materials and the best formula has become one of the important topics in paint production.
The following four steps are usually used in the production of
coatings:
(1) pre-dispersion: the process is mainly mixed and has a certain dispersion effect;
(2) grinding dispersion equipment: the main equipment for coating production. At present, there are a variety of types, common vertical sander, horizontal sander, three-roll grinder and so on. The basket grinder described in this paper is the grinding dispersion equipment in the production of coatings.
(3) paint.
(4) filter packaging.
1 basket grinder status quo
1. The generation of 1 basket grinder
compared to horizontal grinders and vertical grinders that have been used in the coatings industry for decades, basket grinders are new equipment that has only been used in recent years. The head of the basket grinder is secured to a basket filled with grinding media. When working, the grinding basket is immersed in the slurry. The mixing rod in the grinding basket movements at high speed, generating a strong suction force, and the slurry is drawn into the basket containing the grinding medium for dispersion and grinding. And under the effect of centrifugal force, the material in the basket is thrown out of the basket, forming an efficient cycle grinding. Compared with the traditional horizontal sander and vertical grinder, the basket grinder does not require a pump and line system, the grinding basket can be lifted, cleaned and serviced conveniently, easy to change color, less residue, high efficiency and fineness of grinding. The generation of basket grinders complements the limitations of traditional grinding equipment such as horizontal grinders and vertical grinders. At present in Germany, the United States, Singapore and other countries are specialized in basket grinder manufacturing and development of professional factories, domestic enterprises are also actively engaged in basket grinder manufacturing and research work.
1. Application of 2 basket grinders
Since the advent of sanders in the United States in the 1950s, horizontal grinders, vertical grinders and earlier three-roll grinders have been widely used in the coating industry, and these traditional devices have different functions to meet the different needs of coating production. However, there are different limitations. Such as dispersing machine: for the production of high-grade coatings, can only be used for pre-dispersion, but not to achieve the medium and high-grade coatings required slurry crushing effect; However, open operation, so that the working environment is bad, poor operation safety and scattered material loss, complex structure, debugging difficulties, low production efficiency. Based on the above factors, basket grinder has been widely used in coating production since its inception, with its convenient and efficient characteristics.
2 basket grinder status quo
At present, basket grinder in coatings, inks and other multi-variety, multi-color grinding field is more and more widely used. Some people think that because the basket grinder can be used to pull the cylinder for ingredients and grinding dispersion, there is no delivery pump and lines, easy to clean, so it is particularly suitable for small-volume, multi-
varieties of production. This is a misunderstanding of the scope of use of basket grinders. "The immersion grinder——— is simple and efficient, published in the 9th issue of PCI Magazine in 2003, states: "... They consider 'immersive' grinders (basket grinders) suitable for small batches, low viscosity and easy-to-grind products. We don't think they understand immersion grinding techniques or mislead you. ...... Because of its distinctive work efficiency, immersion basket grinders can be called <>." From the use of basket grinder practice, as long as the design is reasonable, a strong cycle so that basket grinder for high viscosity, a large number of materials are also suitable, grinding fineness and efficiency is also ideal.
German VMA has applied basket grinders to the dispersed grinding of 3 t reactors (2004). Domestic enterprises have also successfully applied basket grinders to the dispersed grinding of 3 t reactors in 10 000 t/a coating automation lines, and used them well in practice. If the 3 t reactor uses a traditional horizontal sander for dispersion grinding, it will require a 75 kW high-speed dispersion machine and an 80 to 90 L horizontal sander, and a high-speed dispersing machine will be required to disperse the slurry through the horizontal sander closed The grinding cavity (more than 80 L horizontal grinder volume is already very large) for circular grinding, its efficiency is much lower than the basket grinder, fineness and particle size distribution is not as good as the basket grinder grinding effect in the kettle.
the development of the 3-basket grinder
3. 1 Different structures and types of basket grinders
As mentioned above, there are many countries in the world where decentralized grinding equipment manufacturers are manufacturing and selling basket grinders. The structure of the basket grinder also varies from manufacturer to manufacturer. Can be divided into two categories:
(1) as a fine grinding equipment, before grinding with a basket grinder needs to be pre-dispersed by a high-speed disperser and then by a basket grinder for refined grinding. At present, this kind of basket grinder accounts for the vast majority.
(2) as an integrated equipment for decentralized grinding, no high-speed dispersion machine is required for pre-dispersion, but the two processes of dispersion and grinding will be achieved by a machine of a basket grinder and one process. This is a very innovative basket grinder, for the process of simplification, efficiency improvement, are of positive significance.
3. 2 Scattering and grinding as one basket grinder
The basket grinder is based on an innovative idea: if the basket grinder is turned into two machines: it can be used as a high-speed dispersor when pre-dispersed, and then ground by a basket equipped with grinding media, you can save the high-speed dispersion machine, pump, pipeline and other complex processes and equipment and the attendant installation, maintenance, cleaning costs and work. Pre-dispersion and fine grinding can be done with just one basket grinder. Especially for solid content, high viscosity materials can also achieve a good grinding effect. This is unmatched by traditional equipment in the past. The successful development of this machine has made a new leap in the efficiency and dispersion grinding performance of the basket grinder.
3. 3 Introduction to the first dispersion and then grinding basket grinder
The new first dispersed and then grinding basket grinder inherits the characteristics of the basket grinder dispersing two processes in one machine, one process, and can also be used as a disperser alone (when the dispersion disk in the working position, the grinding basket does not drop). For materials that need to be ground, the function of dispersion and grinding can also be achieved (high efficiency grinding of the material can be performed when the grinding basket is reduced to the working position).
3. 4 Control system introduction (functional optional)
(1) control system with PLC as the control core, text display as the control mode of human-machine dialogue interface;
(2) human-machine dialogue interface can talk to people about equipment maintenance, operation, failure and other information;
(3) operation interface intuitive and convenient, program control, simple operation;
(4) all-round security considerations, the abnormal state of the wrong operation is invalid;
(5) real-time monitoring, fault, error alarm, easy maintenance.
4 Conclusion
basket grinding equipment manufacturers will make more efforts in the future, and continuously improve the applicability, durability, reduce costs to achieve a better cost-effective, and in automatic control to achieve better functions.
coatings industry is in a period of high growth. Basket grinding equipment has the unique advantages of economy, efficiency and energy saving, as long as the equipment manufacturers to provide high-quality pre-sale, sale, after-sales excellent service, basket grinding opportunities have been more and more widely used.