The Underwater pelletizing machine cuts pellets on the plastic steel ejection surface without centrifugal action to eject them, but direct water pressure flows through the nozzle surface to drain.
What is contained in the extrusion system of the Underwater pelletizing machine?
What is the use of the Underwater pelletizing machine?
What are the causes and solutions for the high melting of the Underwater pelletizing machine?
The extrusion system includes a snail, a cylinder, a funnel, a nozzle, and a nozzle. Through the extrusion system, the plastic is plasticized into a uniform melt and continuously extruded by the screw under the resulting pressure.
(1) Screw: It is the most important part of the Underwater pelletizing machine. It is directly related to the scope and productivity of the extruder. It consists of high-strength corrosion-resistant alloy steel.
(2) Cylinders: The cylinder is a metal cylinder that is generally made of alloy steel or composite steel tubes clad with alloy steel, heat resistant, high-pressure resistant, strong, wear-resistant, and corrosion-resistant. The cylinder and the screw are matched to each other to realize the crushing, grinding, melting, plasticization, suction, and compaction of the plastic as well as the continuous and uniform supply of the rubber material to the molding system. In general, the barrel length of an Underwater pelletizing machine is 15-30-fold its diameter, so that the plastic is completely heated and plasticized.
Underwater pelletizing machines can be used for chemical fertilizers, white soot, inorganic salts, chlorinated isocyanic acid, bleaching powder, pesticides, oxides, etc. as well as for industrial recycling dust: such as cast iron dust, lead, zinc, aluminum dust, converter dust, filter dust, grinding dust, etc. The material is forced to be pressed and molded by mechanical pressure without adding a net, and the purity of the product is guaranteed. The process process process is short, energy consumption is low, and performance high. The dry powder is directly granulated without a subsequent drying process, which is more conducive to the connection and transformation of the existing production process. The granular strength is high and the increase in bulk density is more significant than in other granulation processes. The Underwater pelletizing machine is particularly suitable for occasions to increase the specific weight of the product collection. The operating flexibility is great, the range of applications is wide and the crushing force can be adjusted by hydraulic pressure.
Causes analysis: high filter masks, low melting index of polypropylene powder and high feed volume, low temperature of each section of the Underwater pelletizing machine results in the material being incompletely melted, and a low opening rate of the template impede the extrusion of the nozzle head material, etc. The reasons may cause the melting pressure to be too high.
Solution: If the Underwater pelletizing machine produces products with a low melting index, a filter with a low mesh width should be used and the throttle opening should be enlarged to reduce backpressure; the filter should be replaced in time and the quality of different additives and polypropylene powder should be monitored. Contains medium ash. Reduce the feed load. Without compromising the quality of the extruded product, increase the temperature of each section of the cylinder to increase the temperature of the polypropylene melt and increase the flow capacity of the material. After the extruder has been stopped, increase the temperature of the head of the Underwater pelletizing machine and keep it at a constant temperature for a while and rinse and then thoroughly clean the template.
The underwater pelletizing machine have been used in many fields Nanjing JlEYA maintains close relationships with customers in underwater pelletizing machine industry, and is committed to strengthening production and operation, improving quality and safety.
The twin screw extrudernot only has the characteristics of a single-screw extruder, but also has the advantages of convenient feeding, stable extrusion, and convenient exhaust. It is widely used in the production and processing of extruded products.
Why are twin screw extruders warmly welcomed now?
Choose a single-screw extruder or a twin screw extruder?
What are the technical points of the twin screw extruder?
Why are twin screw extruders warmly welcomed now?
The twin screw extruder can not only add more ingredients to the company's products, but also can choose to quickly complete the manufacturing. Considering that "new crown pneumonia" has put every industry into trouble, the market has been looking for a quick turnaround to pay for healthy food. In addition, you may need to make up for the loss of production and sales or increase production and sales based on the current situation. Twin-screw extension can help you, and considering the lower cost and higher production and sales, it can bring more profits.
Choose a single-screw extruder or a twin screw extruder?
The single-screw extruder is used for extrusion processing technology and equipment, and the particle raw materials stay in the extruder for a long time. This means that a single-screw extruder requires a longer period than a twin screw extruder to produce the products required by the enterprise. In addition, the twin screw extruder allows you to better control the complex operation process and actual operation. As everyone knows, these controls are much more complicated. This is very important for foods that need to be mixed and mixed. The production and manufacturing facilities are complete, and the actual effect of twin-screw extrusion is the best. For polymer materials, twin-screw extrusion is also particularly effective. Considering that the design concept of twin screw extruder has a relatively large flexibility, it can be used in many industries for very specific operation processes.
What are the technical points of the twin screw extruder?
In the extrusion process of the twin screw extruder, the material is transformed from the glass state to the molten state. In addition to the balance between the heat required for plasticization of the material and the amount of heat supplied, the material is melted. Pressure is also a very important control indicator. Because the material is affected by the compression ratio of each section of the die resistance screw during the extrusion process, it does not exist under normal pressure. For different die, the compression ratio of each section of the screw is basically constant and immutable. Under the premise of the same extrusion speed, increase or decrease the feed rate, the volume of the screw material in the feeding section will change, and the volume of the material in the exhaust section will remain unchanged, so the compression section of the feeding section changes with the compression ratio, and its melt pressure follows Increase or decrease; under the premise of the same feed rate, increase or decrease the extrusion rate, the volume of the screw material in the feeding section will also change. The volume of the material in the exhaust section remains unchanged, so the compression section of the feed section changes with the compression ratio, and its melt pressure increases or decreases accordingly; the feed speed increases or decreases simultaneously with the extrusion speed, because the volume of the screw material in the feed section remains unchanged , Only due to the increase or decrease of the speed, the melt pressure change.
Due to different fields and different types of twin screw extruder, they are widely used in many industries. To meet these growing demands, Nanjing JlEYA has committed to providing the increasing of twin screw extruder.
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.
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.
Weigh the complete feeding system (silo, feeder and bulk material) through static scales and control the discharge flow of bulk materials through variable speed motors or electric vibrators. Material is discharged from the system (via screw, vibrating tube or trough), the "loss" measured per unit of time (dv/dt) is compared to the required feed rate (preset value), the actual (measured) The difference between the flow rate and the desired (preset) flow rate generates a corrective signal through the dosing controller, which automatically adjusts the dosing rate to maintain the accurate dosing amount without process lag. When the weight measured in the silo reaches the low level of the silo (refilling), the controller will control the feeding system according to the volumetric feeding, and then the silo will be reloaded quickly (manually or automatically), and the weight loss controller will restart . In a batch loss-in-weight system, the design is similar to a continuous loss-in-weight system, however, the accuracy of the final weight of the feed (batch) cycle is higher than the actual feed amount control. The controller accomplishes fast dosing by providing a high dosing signal to the variable speed drive, then transitions to a low dosing control signal for precise control at the end of the batch. Technical parameter
Metering accuracy ≤0.5%
Ingredient accuracy ≤0.5%
Batching measurement control range 0.01-300t/h
Scope of application
Continuous stabilized soil, cement batching in concrete mixing plants, sintering quantitative control feeding, coal powder quantitative control feeding and batching of various thick slurries, etc.
Product introduction of loss-in-weight scale: the loss-in-weight feeder consists of a hopper, a feeder (single and double-shaft screw feeder), a weighing system and a regulator. During operation, the hopper, material and feeder are weighed continuously. As the material is delivered, the actual rate of weight loss is measured and compared to the desired rate of weight loss (set point). Automatically corrects for deviations from setpoint by adjusting feeder rates. Thus, the material can be fed continuously and evenly and accurately.
Applicable scope: granule, powder, calcium carbonate, talcum powder, resin film powder, flour, starch, etc. Powder gravimetric feeder: solves the problem of feeding metering and feeding with poor fluidity while pellet gravimetric feeder solve any bridging problems that may occur.
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.
Degradable plastics refer to a class of plastics whose various properties can meet the requirements of use, remain unchanged during the shelf life, and can be degraded into environmentally harmless substances under natural environment conditions after use. Therefore, it is also called environmentally degradable plastic.
There are a variety of new plastics: photodegradable plastics, biodegradable plastics, light/oxidative/biodegradable plastics, carbon dioxide-based biodegradable plastics, thermoplastic starch resin degradable plastics.
There are two main areas for the use of degradable plastics: one is the area where ordinary plastics were originally used. In these areas, the difficulty of collecting used or post-consumer plastic products will cause harm to the environment, such as agricultural mulch and single-use plastic packaging, and the second is areas where plastics are used instead of other materials. The use of degradable plastics in these areas can bring convenience, such as ball tacks for golf courses, and seedling fixing materials for tropical rainforest afforestation.
Specific applications are:
1.Agriculture, forestry and fishery, plastic film, water-retaining materials, seedling pots, seedbeds, rope nets, slow-release materials for pesticides and agricultural fertilizers.
2.Packaging industry, shopping bags, garbage bags, compost bags, disposable lunch boxes, instant noodle bowls, buffer packaging materials.
3.Sporting goods, golf tacks and tees
4.Hygiene products, women's hygiene products, baby diapers, medical mattresses, disposable haircuts.
5.Medical materials, bandages, clips, small sticks for cotton swabs, gloves, drug release materials, and surgical sutures and fracture fixation materials.
Nanjing Jieya also manufactures twin screw compounding extruder for bio-degradable material. We warmly welcome 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 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 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:
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/