After years of development, plastic extruders have been derived from the original single screw twin screw, multi-screw, and even no screw. Plastic extruder (main machine) can be used with pipes, films, materials, monofilaments, flat yarns, packing belts, extruded nets, plates (sheets), profiles, granulation, cable coating, etc. Matching, forming a variety of plastic extrusion molding lines to produce a variety of plastic products.
1. The extruder is developing in the direction of large-scale, high-speed and high-efficiency
Foreign extruders with screw diameters of 200-250 mm are common, and special extruders with screw diameters larger than 400 mm are not uncommon. Increasing the screw diameter can increase the productivity of the extruder. When the diameter of the screw is doubled, the productivity of the extruder can be increased several times.
High-speed and ultra-high-speed extruders with a rotational speed of more than 300r/min have been used abroad, which has greatly improved the production capacity of the extruder. However, after the rotation speed is increased, problems such as poor plasticization will occur, and many new types of screws, such as separation type, kneading type, barrier type, split type, and combination type, appear. The aspect ratio of the screw also increased from 20:1 to 36:1, and some as high as 43:1.
2, modular
The auxiliary equipment of the extruder has also been perfected and standardized to meet the requirements of different plastic products. Modular production can adapt to the special requirements of different users, shorten the development cycle of new products, and strive for a larger market share; and specialized production can arrange the various system module components of extrusion molding equipment to be fixed-point production or even global procurement. It is very beneficial to guarantee the quality of the whole period, reduce costs and accelerate capital turnover.
3. Intelligent and networked
Extruders in developed countries have generally adopted modern electronic and computer control technology, process parameters for the entire extrusion process such as melt pressure and temperature, body temperature, main screw and feed screw speed, feed amount, each The parameters of the raw materials, the current and voltage of the motor are measured online, and the closed-loop control of the microcomputer is adopted. Some companies have adopted online remote monitoring, diagnosis and control to network control the extrusion molding line. This is extremely advantageous for ensuring the stability of the process conditions and improving the accuracy of the product.
4, customized
In order to adapt to the requirements of new materials and new processes, new or special extruders are constantly emerging. Such as three-screw extruder and planetary multi-screw, no-screw extruder, reactive extruder, two-color extruder, foaming extruder and so on. As China's extruder products are closely linked with strategic new industries, they have the advantages of high efficiency, energy saving and high cost performance. The export to developed countries is mainly low-end, and this part of consumption demand is rigid. Therefore, the plastic machinery industry will have broad market prospects. At the same time, we also need to see the challenges we face!
Industry demand:
(1) From the development of plastic products, provide all-round services such as products, process recipes, equipment and after-sales service to plastic machinery users.
(2) According to the requirements of users, design and manufacture suitable equipment for users to solve their technical difficulties.
(3) Timely draw on the technological development of relevant industries and apply the latest scientific and technological achievements to the industry. Such as the electronics, communications industry and automotive industry, the scientific and technological achievements of the aerospace industry.
(4) Keep up with the progress of materials science and adapt new equipment to the processing of new raw materials.
(5) Strive for high speed, high efficiency and energy saving of equipment operation.
preventive solution:
(1) Breaking the boundaries of the original industry and realizing plastic machinery to serve the larger market.
(2) Continue to learn from foreign advanced products and processes and equipment to develop Chinese plastic presses and improve their technical level.
(3) Avoiding domestic vicious competition and opening up foreign markets.
(4) Concentrate on making a big business in a certain local market.
(5) Increase investment in science and technology, accelerate the absorption of high-quality management and scientific and technical personnel, in order to further develop and strive to reach the international advanced level.
Several types of reactive filler such as Silica Fume or microsilica, metakaolin, work very well in mortar or concrete applications. Owes to secondary reaction with hydrated lime, reactive fillers can improve the long-term strength development and early strength at water immersion condition for various mortars which strength development are hindered by additives such as Redispersible Polymer Powder or Cellulose Ether. Some lightweight fillers like exfoliated vermiculite are also key ingredients for lightweight mortar, thermal insulation mortar or fireproof mortar based on cement or gypsum.
Concrete Additives,Concrete Admixture,Cement Admixtures,Water Reducing Admixtures
Shanghai Na Long Tech Co., Ltd , https://www.na-long.com