








The extrusion system of a single screw extruder includes a screw, a cylinder, a funnel, a head, and a nozzle. The plastic is plasticized by the extrusion system into a uniform melt and is continuous under the resulting pressure through the screw of the extruder head.
What is the relevant information about single screw extruders?
How to improve the product quality of the single screw extruder?
What role does the heating and cooling system play in the single screw extruder?
Each product type in the production line for single screw extruders has its operating characteristics. Only if you know their operating characteristics can you fully measure the efficiency of the machine.
Slug extruder's one of the guys. Record the operating points of single screw extruders and use single screw extruders correctly and sensibly.
The use of a single screw extruder includes several connections such as machine setup, adjustment, test run, operation, maintenance, and repair. Its use has the common characteristics of general machines, mainly in the drive engine and in the speed reduction device.
The working system of the single screw extruder, however, is the extrusion system, which has unique characteristics. When using the single screw extruder, pay particular attention to its properties.
1. About the extrusion product quality of the single screw extruder:
Injection extruders must conform to the raw material formula and process, the product size must correspond to the extrusion equipment and the raw materials must be sufficiently mixed and plasticized to ensure stable extrusion pressure and product quality.
2. Improve extrusion efficiency:
It is related to the selection of the single screw extruder, the screw structure, and the material properties, which are relative and must be considered comprehensively. Simple method, you can choose a larger extruder, the nozzle is opened into a nozzle and several forms.
The heating and cooling system of the inlet extruder consists of a heating device and a cooling device. It is a necessary condition for the smooth running of the extrusion process. The heater and cooling system shall ensure that the polymer material is melted and plasticized and that the temperature conditions during the molding process meet the process requirement.
The cooling system is generally installed in the cylinder, in the screw, and the bottom of the funnel of the inlet extruder. The cylinder cooling may be water-cooled or air-cooled. In general, small and medium extruder air cooling is used; Large series single screw extruders usually use water cooling or a combination of both. The main use of sludge cooling is a central water cooling system, the purpose of which is to increase the rate of solidification of the material, to stabilize the volume of discharges, and, at the same time, to improve product quality. The cooling system at the bottom of the funnel serves mainly to enhance the conveying effect of solids and to prevent the material particles from sticking due to the increase in temperature, blocking the material opening and impairing the supply. In general, in the case of extruders with screw diameters over 90 mm and fast-running screw extruders, a cooling device shall be installed at the bottom of the funnel.
Nanjing JlEYA has worked for many years to meet every customers’ need for single screw extruder. Just connect them.
2022 CIM: Compounding Intelligent Manufacturing Conference is coming.
Nanjing Jieya team warmly welcome your visiting.
Booth no.: E10
Date: 2022.9.14-16
Address: Suzhou, China
See 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.
The underwater pelletizing machine is a smart machine with a touch screen, supports touch input, and is equipped with an Android system. The main engine of the underwater pelletizing machine is an extruder, which consists of an extrusion system, a transmission system and a heating and cooling system.
What are the possible failures of the underwater pelletizing machine and their solutions?
What are the advantages of the underwater pelletizing machine?
What are the applicable materials for the underwater pelletizing machine?
Cause analysis: underwater pelletizing machine cutter wears excessively or the cutter blade is damaged, the particle water flow is too low, the pelletizer vibration is too large, the cutter and the template are not tightly attached, the material melt index fluctuates, and the discharge flow rate is inconsistent. Excessive water temperature and other reasons can cause the shutdown of the underwater pelletizing system and cause the interlocking shutdown of the entire unit.
Solution: After stopping the underwater pelletizing machine, visually check whether the cutting edge of the cutting knife is excessively worn or damaged. If so, replace the cutting knife completely. Check and confirm whether the granular water leaks internally, whether the filter and cooler of the granular water tank are blocked. If they are blocked, they should be cleaned manually; check whether the inlet and outlet pressures of the granular water pump are normal. If not, check the valves on the granular water pump and the pump pipeline. Check whether the alignment between the cutter shaft and the underwater pelletizing machine is out of tolerance, whether the bearing assembly of the cutter shaft is damaged, and whether the cutter rotor is out of balance. During operation, check whether there is any gap in the contact between the four moving wheels of the pelletizing trolley and the guide rail. Control the volatile matter in the polypropylene powder and eliminate the vibration of the cutter and cutter shaft when it flows through the template hole. Reduce the temperature of the hot oil at the template of the underwater pelletizing machine, check the temperature distribution of the cylinder and the template, and whether the flow, pressure and temperature of the cooling water of the cylinder are normal; confirm the time setting for the "water, knife, material" to reach the template to prevent particles The water reaches the template prematurely and freezes the template hole. After closing the head of the underwater pelletizing machine, the feed volume should be quickly increased to the set load of the extruder.
The underwater pelletizing machine is a new model for pelletizing plastic materials that are elastic, easy to foam at low temperature, difficult to form, and have poor flow properties. The underwater pelletizing machine breaks through the traditional method of stranding pelletizing in the past. It overcomes the shortcomings of instability, uneven particles, easy agglomeration, and low output during the granulation of elastomer raw materials.
The underwater pelletizing machine is suitable for EVA, TPU and other materials with high viscosity and high viscosity of elastomers, and also suitable for conventional materials such as PP, PE, ABS, PA, and PC.
The widespread use of underwater pelletizing machines has continuously increased the demand for them in the market. Nanjing JlEYA, as a Chinese pioneer in underwater pelletizing machine, can ensure the machines’ quality and after-sales service.
PVC compounding extruder is divided into RPVC pipe and SPVC pipe, RPVC pipe is easy to cut, welding, bonding, heating can be bent and therefore very easy to install and use. SPVC pipe has excellent chemical stability excellent electrical insulation and good flexibility and colorability this pipe is often used to replace rubber pipe to transport liquid and corrosive media also used as cable casing and wire insulation pipe, etc. So how do choose raw materials and the operation of PVC compounding extruder? The following is a detailed introduction
Here is the content list:
Raw material selection
Safety operating procedures
PVC compounding extruder in the production of hard pipe resin should be selected from the lower polymerization degree of SG-5 resin polymerization degree of the higher its physical and mechanical properties and heat resistance is better, but the resin liquidity is poor to bring some difficulties in processing, so generally choose viscosity of 1.7 ~ 1.8 × 10-3Pa-s SG-5 resin is appropriate. Hard pipe generally uses lead-based stabilizers whose thermal stability is good commonly used trisodium lead but its lubricity is poor usually and good lubricity of lead, barium soap type and use. Processing hard tube lubricant selection and use are very important to consider both internal lubrication to reduce intermolecular forces to reduce the viscosity of the melt are conducive to molding and to consider external lubrication to prevent the melt and hot metal adhesion to make the product surface shiny. Internal lubrication is generally used metal soap type external lubrication with low melting point wax. Filler mainly with calcium carbonate and barium barite powder calcium carbonate to make the pipe surface performance of good barium can improve the molding of the pipe easy to shape both can reduce costs but the amount of too much will affect the performance of the pipe pressure pipe and corrosion-resistant pipe is best not to add or add less filler.
1. Personnel without induction test and operation training cannot operate the extruder independently.
2. People who have poor eyesight and slow response can not be on duty to operate.
3. Before starting the machine to do a good job of environmental health around the PVC compounding extruder equipment, equipment around the pile of items not related to production.
4. Check the safety settings of the extruder before production for damage and test whether it can work effectively. Check whether the connection bolts are loose and whether the safety guards are firm.
5. Check the lubrication parts, remove the dirt, and refill the lubricant.
6. PVC compounding extruder barrel and die heating constant temperature time to ensure that the material temperature does not reach the process requirements when driving production.
7. Before starting the screw drive motor to use the hand plate support V pulley, should be flexible rotation, no blocking phenomenon; then start the lubricating oil pump work 3min before starting the screw rotation at low speed.
8. Screw airlift time should not exceed 2 ~ 3min.
9. PVC compounding extruder barrel before adding material to check the barrel, hopper, there is no foreign matter; raw materials should be free of metal, sand, and other impurities to Prevent damage to the screw.
10. The screw starts, the transmission parts work sound normal, the main motor current within the allowable rated value, before allowing the barrel to add material, adding material should first be a small amount of evenly added material.
11. When adjusting the die gap or clearing the dirty material, the operator should wear gloves and not face the barrel and die to prevent the molten material from spraying out of the die and scalding the body.
12. Extruder driving operation is not allowed to repair, and no one is allowed to do any work on the equipment at this time.
13. In case of the following phenomena, should be an emergency stop.
Bearing parts of the high temperature, lubricating oil (grease) out; motor odor, smoke, or shell temperature is too high; speed box lubricating oil temperature, smoke; transmission parts emit irregular abnormal sound; machine work produces violent vibration; screw suddenly stop rotating.
14. PVC compounding extruder equipment on the safety cover and the location of the safety alarm device is not allowed to change at will, not to mention artificially caused by the malfunction.
15. Find that the equipment leakage, oil leakage phenomenon should be timely maintenance troubleshooting, no water, oil flow around the machine.
If you have questions about how to use the PVC composite extruder, you can contact us on the official website. We are happy to answer for you.
Twin screw extruder is developed based on the single screw extruder, which has been widely used in the molding process of extruded products because of its good feeding performance, mixing and plasticizing performance, exhaust performance, and extrusion stability. So what are the advantages of a twin screw extruder? The following is a detailed introduction.
Here is the content list:
l Wear and tear
l Reduce production costs
l Increase output
l Improve labor efficiency
l High torque and high speed
Wear and tear
Since twin screw extruders are easy to open, the degree of wear of threaded elements and barrel bushings can be detected at any time, so that effective repair or replacement can be carried out. It is not necessary to find out only when there is a problem with the extruded product, which causes unnecessary waste.
Reduce production costs
When producing masterbatches on twin screw extruders, it's usually necessary to alter colors, and if a product amendment is critical, to open the open process space within several minutes, in addition to analyzing the mixing process by looking at the melt profile on the entire screw. The current common twin screw extruder needs to be cleared with a large amount of clearing material when changing colors, which is time consuming, power consuming, and a waste of raw material. The split twin screw extruder can solve this problem. When changing the color, it only takes a few minutes to quickly open the barrel for manual cleaning, so that no or less cleaning material can be used, saving costs.
Increase output
Twin screw snack extruders use side feeding technology to improve the integrity of the material and greatly increase production. The position and shape of the feed opening also have a great influence on feeding efficiency. With the same parameters, the output increases with an increase in the feed area. A rectangular cross section has a higher feed efficiency than a circular cross section for the same inlet area. The use of side by side twin screw feeds is also based on this consideration.
Improve labor efficiency
During equipment maintenance, ordinary twin screw extruders often have to remove the heating and cooling system before the screw can be withdrawn as a whole. In contrast, the split twin screw does not need to be opened by loosening a few bolts and turning the worm gearbox handle device to lift the upper half of the barrel, and then the entire barrel can be repaired. This shortens the maintenance time and reduces the labor intensity.
High torque and high speed
At present, the event trend of twin screw extruders within the world is to develop within the direction of high torsion, high speed, and low energy consumption, and also the impact of high speed is high productivity. The split twin screw extruder belongs to the current class, and its speed will reach and five hundred revolutions per minute. Therefore, its distinctive benefits in process high viscousness and warmth sensitive materials.
In the high speed, high torque core technology, asymmetric and symmetric high torque gearbox currently only Germany and Japan related manufacturers master the core technology, its speed can reach up to 1800 rpm or more, and domestic also master this core technology, such as Nanjing JlEYA extrusion company, is also currently one of the main choices of domestic high end material processing manufacturers, belongs to the domestic independent innovation national encouragement projects.
If you want to buy twin screw extruders, you can consider our cost effective products. We insist on the tenet of "quality first, customer first" and warmly welcome new and old customers to cooperate with us.
The company focuses on twin screw extruders, micro twin screw extruders, plastic extruders, parallel twin screw extruders, and other research and development and manufacturing as the core of the isotropic rotary twin screw mixing and extruding machine, the application range covers the mixing and modification of granulation, polymerization, deswelling, step molding, recycling, and other fields.
Malfunctions that are caused by inadequate or improper maintenance can result in high repair costs and unnecessarily long gearbox down times. Regular servicing and inspection work are therefore imperative!
All servicing and repair work is only allowed to be performed with the gearbox stationary and by trained,authorized and appropriately instructed personnel.
Refilling lubrication oil
The oil level is to be checked regularly.It must never be below the bottom mark. In the case that the oil level drops below the minimum,it is imperative that the lubricant is topped up. The oil is only allowed to be topped up with the drive units shut down. A funnel with a filter is to be used for toppcng up (filter mesh 40um). The gearbox is always to be filled with the same type of oil as used previously It is not allowed to mix different oils or oils from different manufacturers.
Changing oil
The effectiveness of the oil reduces with increasing use due to soiling (foreign bodies and water) and chemical changes(ageing products). When the soiling and/or ageing is/are excessive, it is necessary to change the oil. Regular oil analyses provide information on the effectiveness of the gearbox oils. For larger quantities of oil it is recommended to make oil changes dependent on the results of an oil analysis.A missed oil change increases the risk of damage and can result in premature failure of the gearbox.
The first oil change should be made at approx.2500 perating hours.Subsequent oil changes depend on the state of the oil and are to be performed every 4,000 to 6,000 operating hours, however at the latest after one year.
The gear box is the core part of the twin screw extruders, we shall pay attention to its maintenance for long servicelife.
The main system of the plastic extruder is the extrusion system, which includes screw, barrel, hopper, head, and die. The plastic is plasticized into a uniform melt by the extrusion system and is continuously extruded from the head by the screw under the pressure established in the process. The following are details about the plastic extruder extrusion system introduction.
Here is the content list:
Screw
Barrel
Hopper
Head and mold.
The screw is the most important part of the extruder, which is directly related to the application range and productivity of the extruder and is made of high-strength and corrosion-resistant alloy steel.
The barrel is a metal cylinder, generally made of heat-resistant, high-pressure strength, strong wear-resistant, corrosion-resistant alloy steel or composite steel tube lined with alloy steel. The barrel and the screw cooperate to realize the crushing, softening, melting, plasticizing, exhausting, and compacting of the plastic, and to continuously and evenly deliver the rubber to the molding system. Generally, the length of the barrel is 15-30 times its diameter, so that the plastic is fully heated and fully plasticized as a principle.
The bottom of the hopper is equipped with a cut-off device to adjust and cut off the material flow, and the side of the hopper is equipped with a sight hole and a calibrated measuring device.
The head is composed of alloy steel inner sleeve and carbon steel outer sleeve, the head is equipped with a molding mold, the role of the head is to transform the rotational movement of the plastic melt into a parallel linear motion, evenly and smoothly into the mold sleeve, and give the plastic to the necessary molding pressure. The plastic is plasticized and compacted in the barrel and flows through the neck of the head through a certain flow path through the porous filter plate into the forming mold of the head. The mold core and mold sleeve are properly matched to form an annular gap with decreasing cross-section so that the plastic melt forms a continuous dense tubular cladding layer around the core line. To ensure that the plastic flow channel in the head is reasonable and to eliminate the dead angle of the accumulated plastic, there is often a diversion sleeve placed, and to eliminate the pressure fluctuation of plastic extrusion, there is also a pressure equalization ring set. The head is also equipped with a die correction and adjustment device to facilitate the adjustment and correction of the concentricity of the die core and die sleeve.
The extruder head is divided into an angled head (120o angle) and a right angle head according to the angle between the head material flow direction and the screw centerline. The shell of the head is fixed to the body with bolts, the die inside the head has a die core sitting and is fixed to the head inlet port with a nut, the front of the die core seat is equipped with a die core, the die core and the center of the die core seat has a hole for passing the core line, the front of the head is equipped with an even pressure ring for equalizing the pressure, the extrusion package forming part is composed of die sleeve seat and die sleeve, the position of the die sleeve can be adjusted by bolts through the support to adjust the die sleeve to the die core The position of the die sleeve can be adjusted by bolts through support to adjust the relative position of the die sleeve to the die core, which is convenient to adjust the uniformity of the thickness of the extruded layer.
If you want to buy a plastic extruder or want to know more, you can visit our official website. Our website is https://www.njjyextrusion.com/