The high efficiency of the single-screw extruderis mainly reflected in high output, low energy consumption, and low manufacturing cost. In terms of function, the plastic extruder has been used not only for extrusion molding and mixing processing of polymer materials but its use has been broadened to food, feed, electrode, building materials, packaging, ceramics, and other fields. So how to operate the single screw extruder? The following is a detailed introduction.
Here is the content list:
Preparation work before starting the machine
1. For single-screw extruder extrusion production of materials, should meet the required drying requirements, if necessary, further drying.
2. According to the variety of products, size, select the head specifications, the machine will be installed in the order of the column, installed head flange, die body, mouth die, porous plate, and filter network.
3. Connect the compressed air pipe, install the core mold electric heating rod head heating ring, check the water system.
4. Adjust the gap evenly in all parts of the mouth die and check whether the centerline of the main machine and the auxiliary machine are aligned.
5. Start the single-screw extruder of each running equipment, check whether the operation is normal, and find faults in time to eliminate.
6. Turn on the electric heater, the head, body, and auxiliary machine evenly heated up, to be the temperature of each part than the normal production temperature of about 10 degrees, constant temperature of 30 ~ 60 minutes so that the machine temperature inside and outside the same.
Start-up is an important part of the production, poor control will damage the screw and head, the temperature is too high will cause plastic decomposition, the temperature is too low will damage the screw, barrel, and head. The start-up steps are as follows.
1. Start the machine at low speed, idle, check the screw for any abnormalities and motor, amperage meter current no overload phenomenon, the pressure gauge is normal. Machine idling should not be too long to prevent the screw and barrel-scraping grinding.
2. Gradually add a small amount of material, wait for the material extrusion out of the die, before the normal addition of material. Before the plastic is extruded, no one should be in front of the mouth die to prevent casualties.
3. After the plastic is extruded, it is necessary to lead the extruded material slowly on the cooling and shaping, traction equipment, and start this equipment beforehand. Then, according to the control instrument indication value and the requirements of the extruded products, each link will be properly adjusted until the extrusion operation reaches the normal state.
4. Cutting and sampling, checking whether the appearance meets the requirements, whether the size meets the standard, quickly testing the performance, and then adjusting the extrusion process according to the requirements of quality, so that the products meet the standard requirements.
1. Stop feeding, extrude the plastic in the single screw extruder and turn off the power of the barrel and head for the next operation.
2. Shut off the power of the main machine and the auxiliary machines at the same time.
3. Open the head connection flange, clean the porous plate and various parts of the head, when cleaning, should use copper rods, copper pieces, after cleaning, apply a little oil. Screw, barrel clean up, if necessary, the screw from the end of the machine out of the top, clean up after recovery, in general, available for the transition of material cleanup.
4. Extrusion of polyolefin plastics, usually in the extruder full load shutdown (with material shutdown), when the air should be prevented from entering the barrel, so as not to oxidize the material and affect the quality of the product when continuing production. For polyvinyl chloride plastics, can also stop with material, then close the material door, reduce the temperature at the head connection body (flange) 10 ~ 20 degrees, to stop the machine after the material squeeze net.
5. Close the total power and cooling water main valve.
If you still have questions, you can consult our company. Our company's website is https://www.njjyextrusion.com/
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.
underwater pelletizing machine plays an irreplaceable role in the current industrial production process. Only when the underwater pelletizing machine is used correctly can the greatest effect be achieved.
What problems should be paid attention to when using underwater pelletizing machine?
What is the cause of the friction clutch failure of the underwater pelletizing machine and its solution?
How can the underwater pelletizing machine make the pellets cut out by pelletizing have no pores?
1. Pay attention to the temperature change of the underwater pelletizing machine at any time. When touching the sliver with clean hands, the temperature should be raised immediately. Until the sliver touches your hand, it is normal.
2. When the bearing part of the reducer burns, or is accompanied by noise, it should be repaired in time and refueled.
3. When the bearing parts at both ends of the bearing chamber of the underwater pelletizing machine are hot or there is noise, stop the machine for maintenance and add butter. During normal operation, add butter to the bearing chamber every 5-6 days.
4. Pay attention to the operating rules of the underwater pelletizing machine; such as: the machine temperature is high or low, the speed is fast or slow, and it can be dealt with in time according to the situation.
5. When the operation of the underwater pelletizing machine is unstable, pay attention to check whether the gap of the coupling anastomosis is too tight, and adjust it in time to loosen it.
Reason analysis: The instantaneous starting voltage of the main motor of the underwater pelletizing machine is too low, the friction disc and the friction disc are overheated, the friction disc and the friction disc are aging, and the air pressure of the friction disc is too low, etc., which can cause the clutch to disengage.
Solution: When starting the main motor of the underwater pelletizing machine, avoid peak power consumption and reduce the feeding load. The minimum restart interval is 30 minutes; in summer, when the main motor is restarted more than twice, it should be extended. Interval time or forced cooling with a fan. Blow with instrument wind and wipe off the dirt on the surface of the friction plate and friction plate with a rag. If the underwater pelletizing machine wears a lot or the surface becomes "vitrified", replace the friction plate and friction plate. Confirm whether the air pressure value can make the friction disc and the friction plate fit together.
One: The different materials used by the underwater pelletizing machine must be separated clearly;
Two: The products produced by the underwater pelletizing machine should be dewatered as much as possible after being crushed and cleaned;
Three: The vent hole on the screw of the underwater pelletizing machine should be unblocked.
Nanjing JlEYA has various underwater pelletizing machines that can provide the increasing of products, and make them more effective, reliable, and consistent.
Nanjing Jieya Extrusion Equipment Co., Ltd. (referred to as "Jieya") was established in 2004. It has the manufacturing capacity of various types of production lines with an annual production and sales of more than 350 sets. Its comprehensive capability ranks in the forefront of the Nanjing twin screw extruders industry. The company focuses on the R&D and manufacturing of various production lines centered on co-rotating twin-screw extruders and single-screw extruders. The product applications cover compounding, modified granulation, polymerization, devolatilization, one-step molding, and recyclable resources, etc.
Project Director Mr Chen introduced that every industry has competition, but specific to a certain market segment, the competitors involved are different. Traditional physical blending and modification is the largest market for twin-screw extruders, so the competition is the most intense. For Jieya, the bio-degradable plastic market was changed greatly in 2021, and a considerable part of Jieya’s orders in 2021 also came from this market.
Mr Chen explained that the reason why bio-degradable plastics are singled out from the traditional blending and modification market is that there have been many entrants in this market in the past two years, which has led to the rapid expansion of the market scale. Therefore, from traditional compounding and extrusion to processing bio-degradable plastics, is it necessary to carry out certain technical reserves? Mr Chen said frankly that it depends on how much bio-degradable plastics companies want to achieve. Just like melt blown materials in 2020, some companies have astonishing shipments, and some companies choose to take the quality to a higher level. The bio-degradable material made by special equipment must be of higher quality.
Around 2010, Jieya began to get involved in bio-degradable-related projects. During this period, we saw the ups and downs of major companies, and also witnessed the gradual growth of some companies from small to large. Most of these surviving companies are in the bio-degradable market. They started foreign trade before they became popular, and some companies even achieved a market share of about 30% in the export of Chinese vest bags.
He also talked about some distressing points in the biodegradable market: at present, the Chinese government has not clearly stipulated the definition and criteria of "bio-degradable". For example, some regions regard photo-degradable as a kind of bio-degradable. Many people oppose this. Mr Chen said that at present, most people in the Chinese market think that 'bio-degradable' is compostable and degradable, and garbage must be sorted and recycled before composting is possible.
However, Mr Chen is still very optimistic about the development of bio-degradable plastics. Bio-degradable must be the general trend of future social development, but the specific direction remains to be verified. Jieya has a layout for the main bio-degradable plastic categories, such as targeting for many PBAT projects launched in China in the past two years, we are actively discussing with customers whether we can directly use the twin-screw extruder in the polymerization stage to directly make modified materials (without extruding PBAT raw materials). Jieya has also followed up on the project of carbon dioxide production of PPC bio-degradable materials and PGA synthesized with glycolide. At present, the bio-degradable plastics market is still developing and improving. What we need to do now is to develop the corresponding twin-screw technology with the industrial chain. Based on the accumulated experience of a large number of practical applications to continuously improve the stability of the equipment.
Under the big goal of carbon neutrality, some very big changes have taken place in industries such as home appliances and automobiles. The intuitive impact is that Jieya has recently received some projects for recycling, dismantling, and regranulating waste household appliances, as well as the crushing, recycling, and regranulation of some new energy battery shells, which is also one of the important markets for Jieya in 2021. Mr Chen said that these manufacturers have multiple production lines and large projects, but they are usually new entrants, and usually require suppliers to provide them with whole-plant project planning, so they put forward higher requirements for suppliers' project experience and service capabilities.
Fluorochemicals, another key application area for which Jieya is recognized. Fluoroplastics are also known as "plastic kings". Their corrosion resistance, solvent resistance, weather resistance and temperature resistance are relatively good, so they are often included in the field of special engineering plastics. The most well-known is the PVDF used with lithium battery binder. In 2021, Jieya also undertook some projects in this field.
Mr Chen believes that the Chinese market is developing very fast, and twin-screw extruder enterprises must keep abreast of customer needs in order to gain a foothold in the market. Therefore, Jieya is also seeking new development in the upstream links. For example, the twin-screw devolatilization extrusion unit developed to meet the growing demand of downstream customers for products with low VOC and low residue; as well as corrosion resistance and wear resistance under high temperature conditions. The extrusion unit meets the production needs of special products under severe working conditions.
The success of Nanjing Jieya in the market is inseparable from the technical advantages of its twin-screw extruder equipment: its core components are all self produced, including high-torque gearboxes, extruder barrels, extruder screw elements, screen changer, die, etc. The product quality is stable and controllable, which can meet the personalized customization needs of customers, and the delivery time is flexible. In addition, Jieya stable team has also played a huge advantage. It is said that its sales, technology, management, and after-sales teams have an average of more than 10 years of experience in the industry. They have rich industry experience and are relatively clear about the pain points of various market segments. Provide complete personalized solutions, and can also undertake large and complex complete system projects.
Nanjing JIEYA attend Chinaplas 2021 held in Shenzhen. We sincerely welcome your visiting.
Our booth no.: 7Q25
Time: April 13-16, 2021
Address: Shenzhen World Exhibition Center
Look forward to meet you at there.
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 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/
The difference between single screw extruder and twin screw extruder: one is a screw, the other is two screws. Both are driven by a motor. The power varies with different screw sizes. The power of 50 conical twin screw extruder is about 20kW, and 65 is about 37kW. The output is related to the material and the screw size. The output of 50 conical twin screw extruder is about 100-150kg/h, and 65 conical twin screw extruder is about 200-280kg/h. The output of a single screw is only half than twin screw extruder.
Extruders can be divided into single-screw, twin-screw and multi-screw extruders according to the number of screws. Today, the single-screw extruder is the most widely used and is suitable for extrusion processing of general materials. The twin-screw extruder has the characteristics of less heat generated by friction, relatively uniform shearing of the material, large conveying capacity of the screw, relatively stable extrusion volume, long residence of the material in the barrel, and uniform mixing.
The single-screw extruder occupies an important position both as a plasticizing and granulating machine or a molding and processing machine. In recent years, the single-screw extruder has made great progress. The large-scale single-screw extruder for granulation produced in Germany has a screw diameter of 700mm and an output of 36t/h.
The main sign of the development of single-screw extruder lies in the development of its key part, the screw. In recent years, people have carried out a lot of theoretical and experimental research on screws. There are nearly 100 types of screws. The common ones are separation type, shear type, barrier type, split type and wave type.
From the perspective of single-screw development, although the single-screw extruder has been relatively complete, with the continuous development of polymer materials and plastic products, new and special single-screw extruders with more characteristics will emerge. In general, single-screw extruders are developing in the direction of high speed, high efficiency and specialization.
The twin-screw extruder has good feeding characteristics, is suitable for powder processing, and has better mixing, exhaust, reaction and self-cleaning functions than single-screw extruders, and is characterized by processing plastics and blends with poor thermal stability. It shows its superiority even more.
The main machine of the plastic extruder is the extruder, which is composed of an extrusion system, transmission system, and heating and cooling system. The following is a detailed description of the composition of the plastic extruder.
Here is the content list:
Heating and cooling device
A homogeneous melt is plasticized bypassing the plastic through the extrusion system, which consists of a screw, barrel, hopper, head, and die.
The function of the drive system is to drive the screw, supplying the torque and speed required by the screw during the extrusion process, usually consisting of an electric motor, reducer, and bearings.
The manufacturing cost of the reducer is roughly proportional to its size and weight, provided that the structure is the same. Because the shape and weight of the reducer are large, it means that more materials are consumed in the manufacturing, and the bearings used are also larger, which increases the manufacturing cost.
For a similar screw diameter extruder, the high speed and high potency extruder consume additional energy than the traditional extruder, the motor power is doubled, and also the reducer seat range is raised consequently is critical，however a high screw speed means that an occasional reduction magnitude relation. For the same size reducer, the gear modulus of the low reduction ratio increases compared to the large reduction ratio, and the capacity of the reducer to bear the load also increases. Therefore, the rise in volume and weight of the reducer isn't linearly proportional to the rise in motor power. If the extrusion volume is employed because of the divisor and dividend by the burden of the reducer, the high speed and high potency extruder can have a smaller range and the normal extruder will have a larger number.
In terms of unit output, the small motor power and the small weight of the reducer of the high speed and high-efficiency extruder means that the manufacturing cost per unit output of the high speed and high-efficiency extruder is lower than that of the normal extruder.
Heating and cooling are necessary to enable the plastic extrusion process to proceed.
(1) Extruders usually use electric heating, which is divided into resistance heating and induction heating, with heating sheets installed in each part of the body, neck, and head. The heating device heats the plastic inside the barrel from the outside to warm it up to the temperature required for the process operation.
(2) The cooling device is installed to ensure that the plastic is in the temperature range required for the process. Specifically, it is to exclude the excess heat generated by the shear friction of the rotating screw to avoid the plastic from decomposing, scorching, or shaping difficulties due to the high temperature. Barrel cooling is divided into two kinds of water-cooled and air-cooled, generally small and medium-sized extrusion machine using air-cooled is more appropriate, large is more water-cooled or a combination of two forms of cooling; screw cooling is mainly used in the center of water-cooled, the purpose is to increase the rate of solid material delivery, stabilize the amount of rubber, while improving product quality; but the cooling at the hopper, one is to strengthen the role of solid material delivery, to prevent the plastic grain sticky blockage because of the heating the second is to ensure the normal work of the transmission part.
If you are engaged in the industry related to the extruder, you can consider our cost-effective products. Our company is a leading extruder manufacturer specializing in a twin-screw extruder, micro twin-screw extruder, plastic extruder, and parallel twin-screw extruder in China.