1.You can directly know the wear pattern of quick-wear parts. Thanks to the easy opening, the wear of the threaded elements and barrel bushings can be detected at any time and can be effectively repaired or replaced. No unnecessary waste is caused by the fact that problems with the extruded product are only discovered when they occur.
2.Reduce the cost of production. When manufacturing masterbatches, it is often necessary to change colours and if a change of product is necessary, to open the open processing area within a few minutes time and additionally to analyse the mixing process by looking at the melt profile on the entire screw. The current common twin-screw extruder requires a large amount of clearing material to clear the machine when changing the colour, which is time-consuming, power-consuming and a waste of raw material. The split twin-screw extruder, on the other hand, solves this problem by quickly opening the barrel for manual cleaning in just a few minutes when changing colours, thus saving costs by using no or less cleaning material.
3.Enhance the efficiency of labour. When repairing equipment, ordinary twin-screw extruders often require the heating and cooling system to be removed before the screw can be withdrawn in its entirety. The split twin-screw does not need to be removed, as long as a few bolts are loosened and the upper half of the barrel is lifted by turning the worm gearbox handle device to open the entire barrel for maintenance. This shortens maintenance time and reduces labour intensity.
4.High torque, high speed. The current trend in the world of twin-screw extruders is towards high torque, high rotational speed and low energy consumption, the effect of high rotational speed being high productivity. This is the case with the split twin-screw extruder, which can reach speeds of up to plus 500 rpm. This gives it a unique advantage in the processing of highly viscous, heat-sensitive materials.
5.A wide range of applications for processing a wide range of materials; high output, high quality and high efficiency can be achieved.
The Deficiency of Twin Screw Extruder Machine in Production
Parallel and co-rotating twin-screw extruders, commonly used for plastic modification, plastic dyeing and plastic reinforcement. At present, domestic twin-screw extruders, in the production process, have encountered a variety of problems, such as the following.
- the unstable properties of the pellets during production
- the need for constant recipe adjustment
- the increasing severity of particle defects
- frequent replacement of screw parts.
- the cost of the recipe does not decrease but increases, etc.
The Problems of Twin-screw Extruder
The equipment serves production, so solving problems that arise in production is also a key consideration when designing the equipment. The actual problems are combined to discuss the directions in which twin-screw extruders need to be optimised.
Decrease in physical properties of the product
Plastic melt in the screw extrusion, due to the traditional extruder screw and barrel of the relative fit clearance is too large, resulting in too much backflow phenomenon, resulting in the formulation of the components of repeated shear, excessive shear quickly increased the internal shear heat of the melt, different degrees of damage to the formulation components, such as the early cracking and volatilization of small materials.
The flaw of the particle(Particles with air holes, flow marks, scars, low yield, high power consumption)
A large extrusion gap causes melt backflow, which reduces screw extrusion and conveying capacity per unit time.
Low head pressure; resulting in uncompacted particles.
Low output; counter-current causes repeated shearing, which invariably consumes too much electrical energy and increases granulation costs.
The surface of the granules is not bright, the screw is not easy to clean when the material is replaced, and the barrel is rusty and blocked
The barrel is the core component of the extruder, Kairong Group has substantially improved the precision of the flow paths within the extrusion system. Both the barrel and screw are made of special imported plastic machine special alloys. The barrel and screw are made of a special imported alloy for plastic machines. The surface finish is mirror-like, which reduces frictional resistance to melt advancement and facilitates colour change and cleaning, which is essential for the production of coloured masterbatches and highly demanding plastic masterbatches.
In terms of barrel cooling, Kairong Group uses a dual-channel oil cooling system, which not only avoids rapid cooling of the barrel but also reduces the accumulation of carbon and rust blockage in the barrel cooling holes.
Poor powder dispersion
The threaded sleeve arc tends to the theoretical design value; minimizes the kneading space and improves the mixing function of the threaded sleeve; application analysis, for example, PP and PET two kinds of white masterbatches, requires not only good dispersion, but also high viscosity, if too much shear, the dispersion will, of course, be good, but the viscosity will drop, which directly affects the spinning colouring effect.
Physical and chemical properties do not meet the requirements
Too many shear blocks increased small material shear heat, physical properties decline and chemical properties do not meet the requirements. As the twin-screw is a combination of the block-type threaded sleeves, in general, for color masterbatch, the screw L/D is relatively long (50 machines 44:1 to 48:1; 2090-2280MM).
Positioning the core shaft of the threaded sleeve, generally for involute tooth side positioning, so the linear positioning accuracy of the core shaft is particularly important in determining whether the first and last threaded sleeve phase in the screw combination can overlap in a straight line, which is related to the Archimedes spiral line pinch effect of the threaded sleeve on the two screws; if the accuracy is not high, the threaded sleeve pinch effect will be lost and can only be met by increasing the number of pinches blocks Shear effect, and the number of the shear block is too much, not only increases the resistance and brings too much shear heat, easy to cause the decomposition of raw materials and the loss of formula components, loss of physical properties.
Nanjing Kairong Group is a professional manufacturer of twin screw extruder. Any interest in plastic granules making machine please feel free to contact us.