








The single screw extruder is mainly used for extruding soft and hard polyvinyl chloride, polyethylene, and other thermoplastic. It can be a variety of plastic products such as bubble sheets, extruded pipes, press plates, ribbons, etc. process and can also be used for melting granulation. The plastic extruder is characterized by advanced design, high quality, good plasticization, and low energy consumption. It uses an evolutionary drive and is characterized by low noise development, stable operation, great durability, and long service life.
What are the relevant parameters of a single screw extruder?
What are the properties of a single screw extruder?
For which materials can a single screw extruder be used?
The relevant parameters of the insertion extruder are arranged from left to right: the first field is the plastic machine code as S; the second box is the extruder code as J; the third field is the code for the different construction firms of the extruder. The three bars are combined, the plastic extruder is SJ; the ventilated plastic extruder is SJP; the plastic foam extruder is SJF; the extruder with plastic input is SJW; the plastic shoe extruder is SJE; The cascade plastic extruder is SJJ; the double-screw extruder is SJS; the conical double-screw extruder is SJSF; the multi-screw extruder is SJD. The fourth box is for auxiliary machinery with the code name F; in the case of an extruder unit with the code name E. The fifth parameter refers to the snail diameter and the ratio of length to snail diameter. The sixth field refers to the product's pattern sequences, which in the order of letters A, B, C... is arranged and the sample number is not given in the first sample.
(1) The material support of the inlet extruder is mainly based on friction, which limits the conveyance performance of the inlet extruder. The addition of powder, paste, fiberglass, and inorganic fillers is difficult.
(2) If the head pressure of the inlet extruder is high, the counter current increases, which reduces the productivity of the inlet extruder.
(3) Injected exhaust gas extruder material has a low surface regeneration effect in the suction zone, so the suction effect of the inlet extruder is poor.
(4) Injection extruder is used for certain processes, such as polymer dyeing, heat-resistant powder processing, etc. not suitable. The single screw extruder is a high-speed and high-yield extrusion based on a high level.
single screw extruder series, single screw extruders can be used for the processing of PP, PE, PS, ABS, PMMA, PVC, and other thermoplastic tubes, plates, plates, rods, profile materials, and plastic granulation products. For different raw materials and product specifications, the screw assumes different length-diameter ratios and compression ratios, and the flow assumes different structures. Choose the right cylinder, screw, and drive mechanism to meet the processing requirements of high-quality products.
The use of single screw extruders is becoming increasingly widespread. Nanjing JlEYA has been concentrating on single screw extruders for several years. They will make every effort to meet the needs of users.
Each type of product in the plastic extruder line has its operating characteristics, and a detailed understanding of its operating characteristics is necessary to give full play to the effectiveness of the machine. The following is a detailed description of the operating procedures and maintenance methods for plastic extruders.
Here is the content list:
Operation procedures
Maintenance methods
The plastic extruder is one of the machine types, master the extruder operation points, the correct and reasonable use of a plastic extruder. The use of plastic screw extruder includes a series of links such as installation, adjustment, commissioning, operation, maintenance, and repair of the machine, and its use has the commonality of general machines, mainly in the drive motor and reduction and speed change device. However, the working system of the plastic screw extruder, the extrusion system, is unique, and special attention should be paid to its characteristics when using the plastic screw extruder. Extruder manuals generally have clear provisions for the installation, adjustment, and commissioning of the machine, here the main points of the operation, maintenance, and repair of the plastic screw extruder are briefly described as follows: in particular, to correctly grasp the structural characteristics of the screw, heating and cooling management instrumentation characteristics and assembly, the correct extrusion process conditions, the correct operation of the machine.
1.Pastic extruder equipment should be placed in a ventilated position to ensure that the heat of the motor work prolongs its life; the machine should be kept well grounded.
⒉Regularly check the tool screws, the plastic extruder after 1 hour of use, with tools to tighten the moving knife, fixed knife screws, to strengthen the fixed between the blade and the knife frame; should be regularly filled with lubricating oil to ensure the lubrication between the bearings; to ensure the sharpness of the cutting edge of the tool, should always check the tool to ensure its sharpness, to reduce unnecessary damage to other parts caused by the blunt lack of the blade; regularly check whether the belt is loose, and timely tightening.
3. Restart - Before starting the plastic extruder for the second time, the remaining debris in the machine chamber should be cleared to reduce the starting resistance. Periodically open the inertia cover and pulley cover to clear the ash outlet under the flange, which can cause the powder to enter the shaft bearing.
4. Replacement parts - When replacing knives, the clearance between the moving and fixed knives should be 0.8 MM for crushers over 20 HP and 0.5 MM for crushers under 20 HP. The thinner the recycled material is, the gap can be adjusted appropriately larger.
If you need to know more, you can consult our company. The company focused on co-rotating twin-screw compounding extruders with the core of the various R&D and manufacturing, such as a twin-screw extruder, mini twin screw extruder, plastic extruder, parallel twin-screw extruder, and so on, the application covers compounding mixing modified granulation, polymerization, devolatilization, step molding, renewable recycling, and other fields.
Nanjing Team sincerely invite you to attend The 15th China Chongqing Rubber, Plastics Industry Exhibition.
Our booth no.: S2544
Time: May 27-30, 2021
Address: Chongqing International Expo Center
Wish to meet you at there ;)
The development and application of twin screw extruders are increasingly eye-catching. Many aspects of the performance of single and twin screw extruders that dominate the extrusion industry can no longer meet the requirements of blending, filling, reinforcement, toughening and other modifications.
What is the structure of the twin screw extruder?
How does the twin screw extruder prevent material degradation?
What are the structural characteristics of the twin screw extruder?
The twin screw extruder, a unique modular screw block is designed on the screw shaft, which is broken three times within a pitch, called a mixing screw block. Corresponding to these gaps, there are three rows of mixing blocks arranged on the inner sleeve of the barrel. The pin and the screw reciprocate in the axial direction at the same time in the process of radial rotation. The twin screw extruder moves in the axial direction once every time it rotates. Due to this special movement mode and the effect of mixing and sorting screws and pins, the material is not only sheared between the mixing pins and the irregular trapezoidal mixing blocks. And it is transported back and forth. The countercurrent movement of the material adds a very useful axial mixing movement to the radial mixing. The melt is continuously cut, turned, kneaded and stretched, and the twin screw extruder regularly interrupts the simple Layered shear mixing.
Due to the simultaneous mixing in the radial and axial directions of the twin screw extruder, the mixing effect is enhanced and the best dispersion mixing and distributed mixing are ensured, so the homogenization time is short. In addition, the mutual engagement of the mixing pin and the screw block also improves the self-cleaning ability of the barrel. The twin screw extruder can ensure stable working pressure through proper screw block combination, without uncontrollable pressure and temperature fluctuations, and prevent material degradation in the barrel.
1. The main machine barrel and screw are assembled by building blocks
The barrel of the twin screw extruder is composed of multiple sets of open and closed barrels. The split barrel can be opened quickly and conveniently for easy cleaning and maintenance; the screw is composed of various mixing sleeves on the mandrel Composed of screw block and conveying screw block. The barrel and screw can be flexibly formed into an ideal form according to different types of materials and different technological requirements.
2. Unique design of gear box and swing box
The twin screw extruder realizes the axial reciprocating movement of the screw while rotating. Every time the screw rotates, it reciprocates once, and the thread is interrupted three times, thus producing a strong mixing effect. The mixing effect is in the axial direction rather than the radial direction, and occurs between the thread and the pin. All materials in the screw channel are subjected to uniform shear stress, instead of a thin layer of material being sheared.
Great products begin with the best engineering staff, and Nanjing JlEYA is ready to assist you with your technical requirements for twin screw extruder.
A twin screw extruder is composed of several parts such as a transmission device, feeding device, barrel, and screw, etc. The role of each part is similar to that of the single screw extruder. So what are the main differences between the twin screw extruder and single screw extruder? The following is the detailed introduction
Here is the content list:
l Cross sectional profile
l The way of material transfer
l The material flow velocity field
The difference from the single screw extruder is that the twin screw extruder has two parallel screws in an "∞" shaped cross section. Twin screw extruders for profile extrusion are usually closely meshed and heterogeneously rotating, although a few also use co rotating twin screw extruders, which generally operate at relatively low screw speeds of about 10 r/min. High speed meshing co rotating twin screw extruders are used for blending, venting, or as continuous chemical reactors, with maximum screw speeds ranging from 300 600 r/min. Non engaging extruders are used for mixing, venting, and chemical reactions, and their conveyors are very different from those of engaging extruders, and are closer to those of single screw extruders, although they are fundamentally different.
In the single screw extruder, the solid conveying section is friction dragging and the melt conveying section is viscous dragging. The frictional properties of solid materials and the viscosity of molten materials determine the conveying behavior. If some materials have poor frictional properties, it is more difficult to transfer the material to the single screw extruder if the feeding problem is not solved. In twin screw extruders, especially meshing twin screw extruders, the material transfer is to some extent a positive displacement transfer, the degree of positive displacement depending on the proximity of the screw prongs of one screw to the relative screw grooves of the other screw. The screw geometry of a closely meshed anisotropic rotary extruder yields a high degree of positive displacement transport characteristics.
The flow velocity distribution of the material in a single screw extruder has been described fairly well, whereas the flow velocity distribution of the material in a twin screw extruder is quite complex and difficult to describe. Many researchers have analyzed the velocity field of the material without considering the material flow in the engagement zone, but the results of these analyses are very different from the actual situation. This is because the mixing characteristics and overall behavior of a twin screw extruder depend mainly on the leakage flow that occurs in the engagement zone, yet the flow in the engagement zone is quite complex. The complex flow spectrum of the material in a twin screw extruder exhibits macroscopic advantages that cannot be matched by a single screw extruder, such as adequate mixing, good heat transfer, high melting capacity, good venting capacity, and good control of the material temperature.
If you want to know more, you can consult our company. Nanjing JlEYA is the leading manufacturer extruder manufacturer specializing in a twin screw extruder, mini twin screw extruder, plastic extruder, and parallel twin screw extruder in China, which is widely used in compounding, modification, polymerization, devolatilization, reaction, recycling, etc. After 17 years of development, now we have a 20,000 square meters workshop with annual sales of over 300+ sets, export over 60 countries.
JIEYA has the most experienced technical core team, with extensive experience in system integration of the development manufacturing, materials processing, application technology, and other fields.
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:
Extrusion system
Transmission system
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.
With the development of modern industry, the underwater pelletizing machine has become an important production equipment used in all aspects of production.
What is the working principle of the underwater pelletizing machine?
What is the operating procedure of the underwater pelletizing machine?
What are the reasons why people choose underwater pelletizing machine?
The material using the underwater pelletizing machine will pass through the feeding port, and under the action of the rotating screw, it will be rolled into a dough and roll forward along the screw groove. Due to the shear, compression and agitation of the screw, the material will be further mixed and plasticized. , The temperature and pressure gradually increase, showing a state of viscous flow, and passing through the machine head with a certain pressure and temperature, and finally a product of the desired shape is obtained.
(1) Check the rotation direction of the impeller of the underwater pelletizing machine. From the feed inlet, the impeller should turn counterclockwise, otherwise the motor connection should be adjusted.
(2) The starting sequence of the underwater pelletizing machine and the material conveying equipment is as follows:
Discharge belt conveyor→PL vertical impact crusher→feeding belt conveyor
The crusher must be started without load, and the material can only be fed after the crusher is running normally.
(3) The feed size is strictly in accordance with the feed size specified by the various models. It is forbidden to enter the underwater pelletizing machine with the size of the material larger than the specified size, otherwise it will cause the impeller imbalance and excessive wear of the impeller, and even block the impeller flow path and The central feed pipe prevents the crusher from working normally. When a large piece of material is found, it should be removed in time.
(4) When the discharge belt conveyor stops running, the feeding should be stopped immediately, so the discharge belt conveyor should be interlocked with the feeding system to open and stop. Otherwise, the impeller will be crushed and the motor will be burnt.
(5) The feeding of the underwater pelletizing machine should be uniform and continuous.
(6) During the operation of the underwater pelletizing machine, there must be no violent vibration or abnormal noise, otherwise, it should be stopped immediately for inspection, and the machine can only be driven in order after the fault is removed.
(7) The observation door should be sealed tightly during the working process of the underwater pelletizing machine.
The difference between the underwater pelletizing machine and other similar products is that it has a steady stream of water flowing through the mold surface, and it is in direct contact with the mold surface. The size of the pelletizing chamber is just enough to allow the pelletizing knife to rotate freely across the die surface without restricting the temperature of the water flow. The molten polymer has been extruded from the die, and the rotating knife cuts the pellets. And then the pellets are taken out of the pelletizing chamber by the temperature-regulated water and enter the centrifugal dryer. In the dryer of the underwater pelletizing machine, the water will be drained back to the storage tank, cooled and recycled; the pellets pass through the centrifugal dryer to remove the water.
This is how we see the irreplaceable role of underwater pelletizing machine in our daily lives and industrial production. Nanjing JlEYA, the pioneer of underwater pelletizing machine producing company in China, knows that every application is special. You can go and get more information about them