








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 plastic extruder is a common plastic machinery equipment, in the process of the daily operation of the extruder, the extruder will have a variety of failures, affecting the normal production of plastic machinery, the following we will analyze the extruder failure.
Here is the content list:
Unstable host current
The main motor can not start
The head is not discharged smoothly or blocked
The main electric starting current is too high
The main motor makes an abnormal sound
1. Production reasons.
(1) Uneven feeding.
(2) The main motor bearing of the plastic extruder is damaged or poorly lubricated.
(3) A section of the heater is out of order and does not heat up.
(4) The screw adjustment pad is not correct, or the phase is not correct, and the component interferes.
2. Treatment methods.
(1) Check the feeder, troubleshooting.
(2) Overhaul the main motor of the plastic extruder, replace the bearings if necessary.
(3) Check whether each heater is working properly, replace the heater if necessary.
(4) Check the adjustment pad, pull out the screw to check whether there is interference with the screw.
1. Causes.
(1) There is a mistake in the start-up procedure of the plastic extruder.
(2) The main motor thread has a problem, whether the fuse is burned ring.
(3) The main motor-related chain device to function
2. Treatment methods.
(1) Check the program, reboot the machine in the correct boot sequence.
(2) Check the main motor circuit.
(3) Check whether the lube oil pump of the plastic extruder is started and check the status of the chain device associated with the main motor. The oil pump is not on and the motor cannot be turned on.
(4) The inverter induction power has not been discharged. Turn off the main power and wait for 5 minutes before starting again.
(5) Check whether the emergency button is reset.
1. Causes.
(1) A section of the heater does not work, and the material is not plasticized well.
(2) The operating temperature setting is low, or the molecular weight distribution of plastic is wide and unstable.
(3) There may be foreign substances that do not melt easily.
2. Treatment methods.
(1) Check the heater of the plastic extruder and replace it if necessary.
(2) Verify the set temperature of each section, and if necessary, consult with the technician to increase the temperature setting.
(3) Clean and check the extrusion system and the head.
1. Causes.
(1) Insufficient heating time and high torque.
(2) A section of the heater does not work.
2. Treatment methods.
(1) Apply hand pan machine when starting, if not easy, extend the heating time or check whether each section heater is working properly.
1. Produced by.
(1) The main motor bearing of the plastic extruder is damaged.
(2) The main motor silicon controlled rectifier line in silicon controlled damage.
2. Treatment methods.
(1) Replace the main motor bearings.
(2) Check the silicon-controlled rectifier circuit, if necessary, replace the silicon-controlled components.
Our company's website is https://www.njjyextrusion.com/. If you still have questions, you can contact us on the official website.
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 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.
Nanjing Jieya is a professional manufacturer of twin screw compounding extruders since 2004. Our extruders series include SHJ series, HT series, JY series, SJ series, etc. Today we will tell you the differences between SHJ series twin screw extruders and HT series high torque twin screw extruders from three main points below:
1. Torque grade
The torque rating grade of our SHJ series twin screw extruder is T/A3≤8 while HT series is 9≤T/A3≤13.5. Our HT series adopt high torque gear box, which is suitable for customers that pursuit high efficiency machines.
2. Power transmission
SHJ series use clutch for power transmission while HT series use torque protector, for example, R+W brand, Bibby brand, etc.
3. Output
The output of HT series twin screw extruder is much higher than SHJ series.
So HT series can further improve the performance of extruders.But surely, price is higher than SHJ series.
Today, we loaded 2x40HQ export to Vietnam.
One is SHJ-50 twin screw extruder, the other is SHJ-72 twin screw extruders. Both extruders are used for making filler masterbatch.
Nanjing Jieya is a leading manufacturer of twin screw compounding extruders with over 20 years experience. We will offer you the top quality with best price.
We warmly welcome your inquiry.
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.)
PVC compounding extruder is made by mixing PVC resin with stabilizers, lubricants, and other additives through granulation and then extrusion, or by using powder in one extrusion. what are the application areas of PVC? The following are the details.
Here is the content list:
General soft products
PVC film
PVC foam products
PVC coated products
PVC paste resin
PVC transparent sheet
PVC rigid sheet
Other applications of PVC
General soft products can be extruded into cables, wires, and hoses by the extruder: shoe soles, slippers, various plastic sandals, as well as toys and auto parts by the injection molding machine with various molds.
PVC film After mixing and plasticizing PVC with additives, transparent or colored film of specified thickness can be made by using a three-roller or four-roller calendar, and calendered film can be processed by this method. It can also be cut and heat laminated to process raincoats, tablecloths, curtains, packaging bags, inflatable toys, etc. The wide transparent film can be used for greenhouse, plastic shed, and ground film; the film stretched in both directions can be used for shrink packaging due to its characteristics of shrinkage by heat.
Soft PVC can be used as sandals, insoles, foam slippers, and shockproof and cushioning packaging materials. In addition, it can also be extruded into low-foaming hard PVC sheets and profiles by extruder, which is a new type of building material and can be used as a substitute for wood.
Artificial leather with backing is made by coating PVC paste on cloth or paper and then plasticizing it at 100 degrees Celsius or above (or PVC and additives can be calendered into film and then pressed together with backing); while artificial leather without backing is directly calendered by calender into soft sheet with a certain thickness and then pressed with the pattern. It can be used to make leather bags, leather boxes, book covers, sofas, and car cushions, etc. It can also be made into flooring leather, which is used as the flooring material for buildings.
PVC emulsion or micro-suspension resin is dispersed in a liquid plasticizer to make it swell and plasticize into the plasticized sol, and then add stabilizer, filler, coloring agent, etc. After full stirring for de-bubbling, PVC paste is prepared, and then processed into various products such as coat hangers, tool handles, Christmas trees, etc. by casting, impregnating, or laminating processes.
Impact modifier and organotin stabilizer are added to PVC, which is mixed, plasticized, and calendered into transparent sheets. Then it can be made into thin-walled transparent containers by thermoforming and can be used for vacuum blister packaging such as moon cake boxes, etc. It is an excellent packaging material and decoration material.
PVC hard sheet and plate After adding stabilizer, lubricant, and filler to PVC and mixing, it can be extruded into various caliber hard pipes, shaped pipes, corrugated pipes, and other products by using an extruder, and used as a downpipe, drinking water pipe, electric wire casing or staircase handrail, etc.; the calendered sheet can be overlapped and hot-pressed to make various thicknesses of hard sheets, which can be cut into various desired shapes and can be welded into various chemical resistant tanks, ducts and containers by using PVC welding rod with hot air, etc.
PVC can be processed into rigid profiles using an extruder and used for window and door assembly. In some countries, the doors and windows assembled by PVC rigid profile have occupied the market of windows and doors together with wooden windows and doors, aluminum windows, etc.
If you want to buy PVC compounding extruder, you can consult our company, our company's website is https://www.njjyextrusion.com/