2022 CIM: Compounding Intelligent Manufacturing Conference is coming.
Nanjing Jieya team warmly welcome your visiting.
Booth no.: E10
Address: Suzhou, China
Jieya team wish you have a nice holiday :)
(Nanjing Jieya is a professional manufacturer of twin screw compounding extruders with 20+ years experience and competitive price. We look forward to receive your inquiry.)
Nanjing JIEYA hereby sincerely invited you to attend 2021 China (Hainan) Degradation Exhibition.
Our booth no.: B06
Time: June 23-25
Add: Hainan International Convention and Exhibition Center
We warmly welcome your coming and look forward to cooperate with you ;)
The extrusion technology used by the single screw extruder is making waves in the food production industry. We know that single screw extruder can mass produce enterprise products of various shapes and textures. It allows a seamless and continuous operation process, which means that this means lower costs and higher production and sales.
What are the reasons and solutions for the poor discharge or blockage of the single screw extruder head?
What is the importance of single screw extruder temperature control?
What is the importance of single screw extruder speed control?
1. Reasons: (1) A certain section of the heater does not work, and the material is poorly plasticized. (2) The operating temperature is set too low, or the molecular weight distribution of the plastic is wide and unstable. (3) There may be foreign objects in the single screw extruder that are not easy to melt.
2. Treatment method: (1) Check the heater and replace it if necessary. (2) Verify the set temperature of each section, negotiate with the technician if necessary, and increase the temperature set value. (3) Clean and check the extrusion system and head of the single screw extruder.
Temperature control refers to the temperature of the single screw extruder during plastic extrusion, including the temperature control of the barrel, die and transition body. These temperature controls are related to the viscosity of the material, the sensitivity to temperature, and the aggregation state of the polymer. In general, the temperature of the die head and transition body of single screw extruder is low for medium and low viscosity materials, and the temperature of die head and transition body for high viscosity materials is high, and the fluidity is good.
Speed control means that for single screw extrude processing, if the screw speed increases, the shear rate increases. Thermoplastic melts are mostly non-Newtonian pseudoplastic fluids, and their viscosity decreases with the increase of shear rate, and fluidity Increasing the extrusion output also increases. However, if the shear rate is too large, the melt viscosity is too low, which will cause difficulties in the production and operation of single screw extrude. At the same time, the low-viscosity melt will flow backwards under the action of the screw back pressure, and the leakage flow will increase significantly, which will affect the output to a certain extent. , Again, the screw may even slip at high speeds, so the screw speed should be controlled within a certain range. In addition, in the production process of single screw extrude, the screw speed should be kept as stable as possible to avoid fast and slow. Otherwise, it will cause uneven discharge due to excessive changes in the melt viscosity of the material, which will affect normal production.
Nanjing JlEYA is a single screw extruder manufacturer established for more than five years. We work with customers from design to completion to ensure that all technical requirements are met.
A plastic extruder performs all of the following processes through a barrel with a screw and auger channel. The plastic pellets enter the barrel through a hopper at one finish of the barrel and are then transferred through the screw to the opposite finish of the barrel. What are the working principle and molding principles of a plastic extruder? The following is a detailed description.
Here is the content list:
Pressure and shearing, etc., convert the solid plastic into a uniform and consistent melt and send the melt to the next process. The production of the melt involves processes such as mixing additives such as masterbatches, blending resins, and re-crushing. The finished melt must be homogeneous in consistency and temperature. The pressurization must be high enough to extrude the viscous polymer.
To have sufficient pressure, the depth of the threads on the screw decreases as the distance to the hopper increases. The external heating and the internal heat generated in the plastic and the screw due to friction softens and melts the plastic. The design requirements for plastic extruders often vary from polymer to polymer and from application to application. Many options involve discharge ports, multiple loading ports, special mixing devices along the screw, cooling and heating of the melt with or without an external heat source (adiabatic plastic extruders), the relative size of the gap variation between the screw and the barrel, and the number of screws. For example, twin-screw plastic extruders allow for more thorough mixing of the melt than single-screw plastic extruders. Tandem extrusion uses the melt-extruded from the first plastic extruder as feedstock for the second plastic extruder, which is typically used to produce extruded polyethylene foam.
D L the characteristic dimensions of plastic extruders are the diameter of the screw (D) and the ratio of the length of the screw (L) to the diameter D L/D (D) (L/D. Plastic extruders usually consist of at least three segments. The first section, near the L/D) filling hopper, is the filling section. Its function is to allow the material to enter the plastic extruder at a relatively smooth rate. In general, this section will be kept at a relatively low temperature to avoid clogging the charging channels. The second section is the compression section, where the melt is formed and the pressure is increased. The transition from the charging section to the compression section can be abrupt or gradual (gentle). The last half, the metering section, is adjacent to the plastic extruder outlet and its main operate is that the uniformity of the fabric flowing out of the plastic extruder. In this section, the material should have sufficient residence time to ensure uniformity of composition and temperature.
At the end of the barrel, the plastic melt leaves the plastic extruder through a head that is designed in an ideal shape for the extruded melt stream to pass through.
Another important part is the drive mechanism of the plastic extruder. It controls the rotational speed of the screw, which determines the output of the plastic extruder. The power required is determined by the viscosity (flow resistance) of the polymer. The viscosity of the polymer depends on the temperature and flow rate and decreases with increasing temperature and shear. Plastic extruders are equipped with screens that keep impurities out of the screen. To avoid downtime, the screens should be able to be changed automatically. This is especially important when processing resin with impurities, such as recycled material. The extruder's screw is divided into feeding section, plasticizing, melting section, temperature according to the process parameters of the plastic particles, the model according to the diameter of the screw 20, 36, 52, 65, 75, 95, 120, 135. Plastic particles heated by the movement of the screw to change the original state, there are many types, depending on the specific application. The capacity of the frequency conversion is proportional to the diameter of the screw and then adjusted according to the different raw materials.
The extrusion method of plastic extruders generally refers to the melting of plastic at a high temperature of about 200°C. The melted plastic is then passed through a die to form the desired shape. Extrusion molding requires a deep understanding of the characteristics of plastics and extensive experience in mold design and is a technically demanding molding method.
Extrusion molding is a method of a continuous flow of material through a die by heating and pressurizing in an extruder, also known as "extrusion molding". Compared with other molding methods, it has the advantages of high efficiency and low unit cost.
Extrusion is mainly used for molding thermoplastics, but it can also be used for some thermosets. Extruded products are continuous profiles, such as tubes, rods, wires, sheets, films, wire, and cable cladding, etc. In addition, it can also be used for mixing, plasticizing and granulating, coloring, blending, etc. plastics.
The extruded products can be called "profiles", which are also called "profiles" because of their irregular cross-sectional shape.
A single-screw extruder consists of an Archimedes screw rotating in a heated barrel. It is widely used because of its simple structure, easy manufacturing, high processing efficiency, and low price, and is the most technically mature and used type of extruder at present. The following is a detailed introduction to single-screw extruders.
Here is the content list:
The design concept of a single-screw extruder
Single-screw extruder features
Uses of single screw extruder
(1) Single-screw extruders are high-speed, high-output extrusions based on high quality, and the design concept of low-temperature plasticization ensures the extrusion of high-quality products. Two-step overall design to strengthen the plasticizing function and ensure the adjustment of high-performance extrusion.
(2) A special barrier of the single-screw extruder, integrated mixing design to ensure material mixing effect and high torque output, extra-large thrust bearing.
(3) The gears and shafts of a single screw extruder are high-strength alloy steel, carburized, ground teeth treatment, high hardness, high finish, and ultra-low noise. PLC intelligent control, the linkage between main and auxiliary machines is possible.
(4) Single screw extruder easy to monitor human-machine interface, easy to understand the processing and machine status, and the control method (temperature control instrument) can be changed as needed.
(5) The material of the single screw extruder is 38CrMoAL/A nitride treatment, which is wear-resistant. It has a combination of air-cooled and water-cooled cooling for strict temperature precision control, and the unique air inlet design makes it a perfect water-cooling device.
(6）Single screw extruder with grooved surface feeding bottom sleeve of screw barrel has enhanced feeding function, which provides a guarantee for high speed and high output extrusion.
1. Hard gearbox, AC or DC stepless drive speed regulation.
2. New screw structure, melt and mix uniformly to ensure low melt temperature and high output
3. Screw barrel material adopts nitride steel 38CrMoAIA nitride treatment, and the surface alloy treatment has higher hardness.
4. Cast copper, cast aluminum heater, air-cooled and water-cooled according to requirements.
5. Advanced electrical control system of single screw
Pipe extrusion of single-screw extruder: it is suitable for PP-R pipe, PE gas pipe, PEX cross-linked pipe, aluminum-plastic composite pipe, ABS pipe, PVC pipe, HDPE silicon core pipe, and various co-extruded composite pipes.
Sheet and plate extrusion: applicable to PVC, PET, PS, PP, PC, and other profiles and plates extrusion. Extrusion of various other plastics such as silk, rod, etc.
Profile extrusion: adjusting the extruder speed and changing the structure of the extrusion screw can be applied to the production of various plastic profiles such as PVC, polyolefin, etc. Modified pelletizing: It is suitable for blending, modifying, and enhancing pelletizing of various plastics.
Nanjing JlEYA is a leading extruder manufacturer specializing in a twin-screw extruder, micro twin-screw extruder, plastic extruder, and parallel twin-screw extruder, which are widely used in compounding, modification, polymerization, devolatilization, reaction, recycling, and other fields. After 17 years of development for many years, now we have a 20,000 square meters plant, 300+ sets of annual sales, and export to more than 60 countries.
The structure of the engineering plastic twin screw extruder barrel is basically similar to that of the single-screw extruder screw barrel. From the appearance structure, the twin-screw extruder barrel is also divided into an integral barrel and a segmented barrel. The engineering plastic twin screw extruder is an upgrade of the single screw extruder, which has also greatly improved the efficiency of use.
What are the reasons why people choose engineering plastic twin screw extruder?
What is the workflow of engineering plastic twin screw extruder?
What are the essential devices in the engineering plastic twin screw extruder?
1. Improve labor efficiency
When the equipment is repaired, engineering plastic twin screw extruder only needs to loosen a few bolts, turn the worm gear box handle device to lift the upper part of the barrel to open the entire barrel, and then perform repairs. This not only shortens the maintenance time, but also reduces the labor intensity.
2. High torque and high speed
The development trend of engineering plastic twin screw extruder in the world is towards high torque, high speed, and low energy consumption. The effect of high speed is high productivity. engineering plastic twin screw extruder belongs to this category, and its speed can reach 500 rpm. Therefore, it has unique advantages in processing high-viscosity, heat-sensitive materials.
3. Wide range of applications
engineering plastic twin screw extruder has a wide range of applications and can be applied to the processing of a variety of materials
4. High output, high quality
engineering plastic twin screw extruder has other advantages of ordinary extruder, and can achieve high output, high quality and high efficiency.
The engineering plastic twin screw extruder used for profile extrusion is usually tightly meshed and rotated in different directions, although a few also use co-rotating twin screw extruders, generally operating at a relatively low screw speed, about 10 r/ min. The high-speed meshing co-rotating engineering plastic twin screw extruder is used for compounding, venting or as a continuous chemical reactor. The maximum screw speed of this type of extruder is 300-600r/min. Non-intermeshing extruder is used for mixing, venting and chemical reaction. Its conveying mechanism is quite different from intermeshing extruder, which is closer to the conveying mechanism of single screw extruder, although there are essential differences between the two.
Among the straightening devices used in engineering plastic twin screw extruder, the most common one is eccentric, and various types of bending of the core are one of the important reasons for the insulation eccentricity. In sheath extrusion, scratches on the sheath surface are often caused by the bending of the cable core. Therefore, the straightening device in various engineering plastic twin screw extruder is indispensable. The main types of straightening devices are: drum type (divided into horizontal and vertical); pulley type (divided into single pulley and pulley block); winch type, which has multiple functions such as dragging, straightening, and tension stabilization; Press wheel type (divided into horizontal type and vertical type), etc.
The engineering plastic twin screw extruders are used more and more widely in daily life, but its quality has a great influence on the experience of use. Nanjing JlEYA has focused on the production and development of engineering plastic twin screw extruders for more than several years, and they have always put the needs of customers as their top priority.
The single screw extruder is mainly composed of 3 parts: extrusion system, transmission system, and heating and cooling system. The following is a detailed introduction to the basic structure of the single screw extruder.
Here is the content list:
Heating and cooling system
The main role of the extrusion system of the single-screw extruder is to melt and plasticize the polymer material to form a uniform melt, to realize the transformation from the glassy state to the viscous flow state. And in this process to establish a certain pressure, by the screw continuous extrusion delivery to the head die. Thus, the extrusion system plays an important role in the molding quality and output of the extrusion process.
The extrusion system mainly includes the feeding device, screw, and barrel, which is the most critical part of the extruder, of which the screw is the heart of the extruder, the material through the rotation of the screw in order to move in the barrel and get pressurized and part of the heat.
The drive system of a single screw extruder is usually composed of a motor, reducer, and bearing, whose role is to drive the screw and supply the torque and torque required by the screw in the extrusion process. During the extrusion process, the screw speed is required to be stable and does not change with the change of screw load to ensure the uniform quality of the product. However, in different situations, the screw is required to be able to achieve variable speed in order to achieve a machine that can adapt to the requirements of extruding different materials or products of different shapes. In most extruders, the change of screw speed is achieved by adjusting the motor speed. The drive system of the single-screw extruder is also equipped with a good lubrication system and a device for rapid braking.
The heating and cooling system of a single screw extruder consist of a heating device and cooling device, which are necessary for the extrusion process to be carried out smoothly. The heating and cooling devices must ensure that the polymer materials are melted and plasticized and the temperature conditions during the molding process meet the process requirements.
The cooling device is generally set up in the extruder barrel, screw and hopper bottom, and other parts. Barrel cooling can be water-cooled or air-cooled, air-cooled is generally used for small and medium-sized single-screw extruders; large single-screw extruders are mostly water-cooled or a combination of the two forms. The cooling device at the bottom of the hopper is mainly to strengthen the solid material conveying effect, to prevent the material particles from becoming sticky due to the heating, blocking the material mouth and thus affecting the feeding. Generally, for extruders with a screw diameter of 90mm or more and high-speed extruders, a cooling device must be installed at the bottom of the hopper.
Our company focuses on twin-screw extruders, micro twin-screw extruders, plastic extruders, parallel twin-screw extruders, and other kinds of research and development and manufacturing as the core of the isotropic rotary twin-screw compounding extruder. If you still want to know more, you can consult our company.