The plastic raw material processing process of the blister machine is mainly to melt, flow, and cool into a finished product after the rubber particles are heated and then cooled. It is also a process in which the plastic changes from particles to different shapes. The following will discuss the different stages. To explain the process.
1. Blister machine melting
The heater allows the raw material particles to gradually melt into a fluid flow, which is mainly suitable for temperature adjustment of different raw materials. Increasing the temperature will tend to speed up the flow of raw materials, which can increase efficiency but may not guarantee yield. It must be suitable Balance.
In addition, the good effect and the characteristics of high thermal cracking of PP are that it is best to make the raw materials smoothly flow to the die during production to avoid insufficient filling or backflow. Backflow means that the flow of raw materials is faster than the output rate. The increase in average flow efficiency is equal to the increase in MFR, which is one of the available processing methods.
Blister machine tightening device
However, the abnormal MFR distribution may lead to increased instability, which may increase the defect rate. However, the PP product is not a product with high dimensional precision because of the application, so the impact is not big.
2. Blister screw
Most of the PP processing is driven by the screw to drive fluidity, so the design of the screw has a great influence. The size of the diameter affects the output, and the compression ratio affects the pressure value and the output and the effect of the finished product. This also includes a variety of materials. The mixing effect.
The raw material flow mainly depends on the heater, but the frictional heat of the raw material will also generate frictional heat to accelerate the fluidity, so the screw compression ratio is small and the flow is small, and the rotation speed must be increased. The frictional heat will be more than that of the screw with a large compression ratio.
Features of high-speed vacuum blister machine
Therefore, it is often said that there is no master in plastic processing, and the person who carefully understands the performance of the machine is the master. The heating of raw materials is not only a heater, but also the frictional heat and suffocation time.
So this is a practical problem, and experience helps solve production problems and efficiency. If the screw needs to have a particularly good mixing effect, sometimes two-stage different screws or twin-shaft screws are designed and different types of screws are divided into sections to achieve various mixing effects.
3. Blister machine mold or die head
The plastic reshaping of the blister machine relies on the mold or die head. The injection molded product is three-dimensional, and the mold is also more complicated. The shrinkage rate must be considered. The others are flat, strip, and needle-shaped continuous product molds. Special shapes are classified as special shapes and need to pay attention to the problem of cooling and shaping immediately.
First board automatic blister machine purchase
Most of the design of the blister machine is like an injection syringe, and the extrusion force driven by the screw will cause huge pressure on the small outlet, which improves the production efficiency. When the die head is designed as a flat surface, how to make the raw materials evenly distributed on the entire surface, the design of the hanger die head is very important, and the exquisite pressing opportunity increases the stable raw material supply of the fish gill pump.
4. Cool
In addition to the sprue gate pouring raw materials, the injection mold also has a cooling water channel cooling raw material design. The extrusion molding relies on the cooling water channel in the roller to achieve the cooling effect, except for the air knife, the cooling water is directly poured on the blowing bag, and the cooling method such as hollow blowing.
Blister machine extension
Automatic vacuum blister machine
The reprocessing and extension of the finished product will enhance the effect. For example, the strapping belt is driven by the front and rear rollers at different speeds to cause the extension effect. The tensile strength of the oriented extension part of the finished product is strengthened and it is not easy to tear, but it is very easy to tear in the horizontal direction.
Molecular weight distribution also affects the extension effect during high-speed production. All extruded products including fibers have different extensions. Vacuum and pressure forming can also be regarded as another form of extension.
6. The blister machine shrinks
Any raw material has the problem of shrinkage. The shrinkage is caused by thermal expansion and cold shrinkage and internal stress generated during crystal formation. Generally speaking, thermal expansion and contraction are easier to overcome. It can be done by extending the cooling time in processing, and continuing to maintain the pressure. The crystalline raw material often has a larger shrinkage difference than the amorphous material, which is about one thousandth for PP. Sixteen, but ABS is only about four thousandths. This part of the difference is very big to overcome on the mold, or often add additives to reduce the shrinkage to overcome, the extrusion plate is often added with LDPE to improve the necking problem.
Shenzhen Yonghengsheng Machinery Manufacturing Co., Ltd. has been committed to research and development for 16 years to provide Shenzhen blister machine, Shenzhen blister machine, Shenzhen vacuum blister machine, Shenzhen thick film blister machine, Shenzhen blister machine, Shenzhen thermoplastic molding machine, Plastic machine hotline: 0755-84817776
