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~

Dear Customers,

Nanjing Jieya is going to attend 18th China (Chengdu) Rubber, Plastic and Packaging Industry Exhibition.

We warmly welcome your visiting.

Time: 15-17th September, 2022

Booth number: 4132 in hall 4

Address: Chengdu Century New International Convention and Exhibition Center

Nanjing Jieya Extrusion Equipment Co, Ltd. is a professional manufacturer of twin screw compounding extruders with over 20 years experience in China. If you have any requirement, please kindly feel free to contact us by ella@njjieya.com.

First of all, the twin-screw extruder has the extruder principle of the single-screw extruder: solid conveying, melting, pressurization and pumping, mixing, stripping and devolatilization, but it is not simply the case. The research on twin-screw extrusion theory started late, coupled with its many types, complex screw geometry, and complex extrusion process, which brought many difficulties to the research. On the whole, the research on twin-screw extrusion theory is still In the initial stage, this is the so-called “more skill than science”. From the research of its extrusion process, it is roughly divided into three links:

  1. The change of the physical state of the polymer in the extrusion process, the principle of conveying solid melt The truth and laws of conveying and exhausting are established, and a mathematical and physical model is established to guide the design of the twin-screw extruder and the optimization of the extrusion process.
  2. It is necessary to clarify the extrusion process of two or more polymers and materials
  3. As a twin-screw extruder, the reaction process, speed, performance and screw configuration during extrusion reaction molding. The intrinsic link between operating conditions was modeled and used to guide reactive molding extrusion.

Nanjing Jieya team wish you have a nice holiday!

(We’re a China leading manufacturer of twin screw extruders, single screw extruders, two stage extruders and twin screw lab extruders with 20 years experience.)

 

Wear condition

Due to the convenience of opening, the wear level of the screw elements and the liner of barrel can be found at any time, so that effective maintenance or replacement can be carried out. It will not be discovered when there is a problem with the extruded product, causing unnecessary waste.

Reduce manufacturing cost

When making masterbatches, it is often necessary to change the color, if necessary to change the product, open the open processing area within a few minutes, and also analyze the mixing process by observing the melt profile over the entire screw. When changing the color of the ordinary twin-screw extruder, it needs to use a large amount of cleaning material to clean the machine, which is time-consuming, power-consuming and wastes raw materials. The split-type twin-screw extruder can solve this problem. When changing the color, the barrel can be quickly opened for manual cleaning in a few minutes, so that no or less cleaning materials are used, which saves costs.

Improve labor efficiency

During equipment maintenance, the heating and cooling systems of the common twin-screw extruder are often removed first, and then the screw is pulled out as a whole. The split-type twin-screw does not need, just loosen a few bolts, turn the worm gear box handle device to lift the upper half of the barrel to open the entire barrel, and then carry out maintenance. This not only shortens the maintenance time, but also reduces the labor intensity.

High torque, high speed

The development trend of twin-screw extruders in the world is to develop in the direction of high torque, high speed and low energy consumption. The effect of high speed is high productivity. Split-type twin-screw extruders belong to this category, and its rotational speed can reach 500 rpm. Therefore, it has unique advantages in processing high-viscosity and heat-sensitive materials.

Wide range of applications

Wide range of applications, suitable for processing a variety of materials

High yield, high quality

With other advantages of ordinary twin-screw extruder, it can achieve high output, high quality and high efficiency.

Nanjing Jieya is a professional manufacturer of twin screw compounding extruders since 2004.We have different pelletizing systems to meet customers’ requirements.Today we will briefly introduce 4 main pelletizing systems below:

Water Cooling Strand Pelletizing

In strand pelletizing, polymer strands exit from the die head and are transported through a water bath. After cooling, the strands are cut into the pellets using the pelletizer.

This pelletizing system is suitable for filler/color masterbatch and engineering plastics.

It has the advantage of low cost and easy operation.

Air Cooling Strand Pelletizing

In air cooling strand pelletizing, polymer strands exit from the die head and the strands are cooled by conveyor belt and automatically conveyed to the strand pelletizer. The cooling is done by special air fans with high cooling capacity.

Air cooling strand pelletizing line can be used to processing and application of partial high polymer material, including PVC, LLDPE, masterbatch, hihg filling caco3 masterbatch, degradable masterbatch, high density carbon masterbatch, and so on.

Underwater Pelletizing

Underwater pelletizing system is good for most of polymers. Especially for TPU and TPV or similar elastomer, its advantage plays well.

It consists of drive valve, die head, pelletizing unit, bypass line, water recycling unit and centrifugal dehydrator.

It is widely used for elastomer plastics, modified plastics, hot melt adhesive, micro plastics, biobased plastics, medical plastics, recycled plastics, etc with the advantage of wide applications and high efficiency.

Water Ring Die Face Pelletizing

For water ring die face pelletizing , molten polymer flows into multiple holes arranged in a circular pattern in a die plate and is cut into pellets as it emerges from the die face. The cutting is accomplished by a series of rotating knives that are also arranged in a circular pattern. After that, it goes into the centrifugal dewatering for water removal.

It is suitable for filler masterbatch, carbon black masterbatch, grafting compounding, etc.

Kindly feel free to contact us if you have any requirements.

Nanjing Jieya is a professional manufacturers of twin screw extruders and single screw extruders with over 20 years experience. We warmly welcome your inquiry~

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.

The meshing co-rotating twin-screw extruder has excellent mixing and good adaptability. It is currently one of the preferred continuous mixing equipment for polymer modification (blending, filling, reinforcement, reactive extrusion). It is most commonly used in equipment. The most common among users is that a piece of equipment is often used, and the replacement of the product is only achieved by replacing the machine head. In fact, the meshing co-rotating twin-screw extruder has an excellent performance: its combined screw and barrel are’universal’-that is, by changing the combination order of the screw and barrel, it can realize the different materials and formulations best use effect.
However, in my country, many users of co-rotating twin screw extruders do not seem to understand or pay much attention to this point. Some enterprises (even scientific research institutes), with multiple products or topics, always use a twin-screw extruder, but since the twin-screw extruder was purchased and scrapped, the screw (barrel) was hardly disassembled After the combination, always use the kind of combination provided by the manufacturer, a screw (barrel) combination in the end. It is conceivable that this will not achieve the desired effect.
The extrusion process of the material in the meshing co-rotating twin-screw extruder is a complex and changeable process, which is affected by many factors. A slight development may affect the performance of the product. In summary, there are three main The influence is the screw configuration (barrel configuration), material characteristics and operating conditions.
The screw and barrel of the co-rotating twin screw extruder are combined. The screw is composed of several threaded components, such as threaded conveying components, kneading disc components, toothed disc components, etc.; its barrel is also composed of different barrel sections (closed, with exhaust port, with liquid filling port, feeding port) . Users can combine different types and different numbers of thread (barrel) components in a certain order according to specific materials, formulations and performance requirements of the mixture to be prepared, which can efficiently complete the planned mixing task. At this time, the combination of screw and barrel is special. If the requirements of materials, formulations and mixing performance of the preparation are changed, the screw and barrel should be recombined to adapt to the new requirements. This is the versatility of this machine.
However, in actual production, there is often a phenomenon that a combination of screw and barrel can cope with multiple formula products. Strictly speaking, a screw combination only has a good mixing effect for one or similar formulations and mixing processes. Therefore, in addition to in-depth understanding of the materials and formulations used and the mixing tasks to be completed, the users of this machine must also understand the performance of the co-rotating twin screw extruder, especially various thread (barrel) components Have a clear understanding of the performance and combination rules and application occasions. The screw-barrel assembly is generally carried out by a combination of experience-theory-experiment. Some twin-screw extruder manufacturers may also provide 1 or 2 combinations according to user requirements. But more combinations depend on users to develop according to their own products and formulas.

Extruder is an important equipment for plastic molding processing and granulation. Normal use of extruder can give full play to the efficiency of the machine and maintain a good working state. Careful maintenance must be carried out to prolong the service life of the machine.
The main faults of the extruder are abnormal noise, abnormal noise and abnormal vibration caused by wear or damage of transmission components, poor lubrication, etc., as well as stuck foreign objects and blocked materials.
In order to avoid failures, in addition to strictly performing daily maintenance, maintenance and repairs according to requirements, you also need to know these:
First, the extruder screw wear
1. Causes of extruder screw wear
The normal wear of the screw and barrel of the extruder mainly occurs in the feeding zone and the metering zone. The main cause of wear is caused by the dry friction between the chip particles and the metal surface. When the chip is heated and softened, the wear is reduced.
Abnormal wear of the screw and barrel will occur when the screw loop and foreign body are stuck. The loop refers to the screw being locked by the condensed material. If the screw extruder lacks good protection devices, the powerful driving force may be broken. Screw jamming will produce unusually large resistance, causing serious damage to the screw surface and serious scratches on the barrel. Scratches on the barrel are difficult to repair. The design principle of the barrel ensures that the service life is longer than that of the screw. For the normal wear of the barrel, it is generally not repaired. The method of repairing the screw thread is often used to restore the radial clearance of the inner bore of the barrel and the outer diameter of the screw.
2. The solution to the screw wear of the extruder
The local damage of the screw thread is repaired by the method of surfacing special anti-wear anti-corrosion alloy. Generally, inert gas shielded welding and plasma argon arc welding are used, and metal spraying technology can also be used for repair. First, grind the outer surface of the worn screw to a depth of about 1.5mm, then weld the alloy layer to a sufficient size to ensure sufficient machining allowance, and finally grind the outer diameter of the screw and the side of the thread to the outer dimension of the screw size.
Second, abnormal noise
1. If it occurs in the reducer, it may be caused by bearing damage or poor lubrication, or it may be caused by gear wear, improper installation adjustment, or poor meshing. It can be solved by replacing bearings, improving lubrication, replacing gears or adjusting gear meshing.
2. If the noise is a sharp scraping sound, the deflection of the barrel should be considered, which may cause the possibility of scraping the shaft head and the transmission sleeve. It can be solved by adjusting the barrel.
3. If the barrel emits noise, the screw may be bent or the set temperature is too low, which may cause excessive friction of the solid particles. It can be processed by straightening the screw or increasing the set temperature.
Third, Abnormal vibration
If this situation occurs at the reducer, it is caused by the wear of the bearings and gears, and the bearing or gear can be replaced. If it occurs at the barrel, it is due to the mixing of hard foreign materials in the material. If necessary, install a strong magnetic device in the hopper to absorb iron filings.
Forth, Ring-shaped plugging material at the entrance of the screw
This kind of failure is mainly due to the cooling water cut-off or insufficient flow rate. It is necessary to check the cooling system and adjust the cooling water flow and pressure to the specified requirements. It is also possible that a large regrind in the raw material blocks the feed port and the feed port needs to be cleaned.