What is medical extrusion: Main steps in extrusion Process?
29 January 21
Advantages and Disadvantages of Extrusion
For efficient and high-quality processing of polymers, medical extrusion punching technique has been developed. The continuous technological process involves forcing the melt of the starting material through the hole to form the finished product. Extruders are common for the production of:
- Sheets
- films
- Pipelines
- diffusers for lamps
- protective sheaths of wires and cables
- and other molded blanks with a constant cross section
General characteristics of the medical extrusion method
The wide functionality of modern extruders allows technologists to work with a variety of raw materials within the framework of production tasks. The following polymers can be successfully applicable:
- shockproof plastic
- elastomer
- nylon
- polyvinyl chloride
- Polypropylene, etc.
The medical extrusion technology also allows passing various rubber, starch-containing and protein-containing mixtures, and plastics. Moreover, it comes through the extrusion forming head.
Extrusion Benefits
When molding articles with a constant cross-section, the technique provides greater flexibility. Similarly, it allows for mass production of parts and blanks. For this purpose, one or more types of polymers are good to use as raw materials. It has extrusion and other advantages that provide the technology with a stable competitive position in various industries.
- Budget costs
A solid injection of capital does not require when launching a complete production line. Furthermore, the method is unique by its minimal cost.
Sustainability
In production, you can recycle raw materials. Moreover, it reduces the amount of waste and pollution on the planet to maintain an ecological balance.
Continuous work
The medical extrusion die-forming line runs continuously. Therefore, it allows factories to operate 24 hours a day with multiple shifts. It is to achieve desired profitability. Enterprises are effectively increasing their turnover and expanding the scale of their activities.
Medical extrusion Refinement
Upon completion of the molding, the parts remain warm, so they can be further modified. If necessary, we can adjust the geometry, dimensions and other parameters in accordance with the requirements of the established standards. Post-extrusion processing is one of the ways leading to the reduction of factory rejects and defects to extremely low values.
Speed
In many companies, large quantities of parts from polymer melt produce in the shortest possible time. Medical extrusion comes by high speed. So there are no problems with the release of the agreed volume of commercial products. Similarly, its quality of which strictly complies with the standards.
Automation
All stages are automated. Moreover, the probability of human error reduces. The workshops use equipment that has a prolonged resource, simple control, and additional options.
Disadvantages of medical extrusion technology
Some disadvantages of extrusion molding should not be ruled out. This format for the production of molded products from plastic and polymers restricts the manufactured product line, imposes some restrictions on the format of products.
The difference in size is also noted, which occurs due to the expansion of plastic raw materials due to exposure to temperatures. It is difficult to reliably predict or predict the exact degree of expansion, because many phenomena affect this indicator.
This means that the manufacturer must prepare for a possible deviation of the overall dimensions of the goods from the standard established dimensions.
How plastics are extruded?
More than 50% of the thermoplastics on the market come by extrusion. This technology assumes continuous forcing of the polymer raw material melt through the forming head. The profile of the finished products comes by the geometry of the extrusion hole. And their length is not specific by anything.
Main steps in Medical Extrusion
The first stage of the production process is the supply of prepared plastic raw materials. They are in the hopper, into the extruder barrel. These can be:
- Granules
- Powders
- Flakes
Auxiliary additives present in the composition to improve the performance properties of finished products – UV inhibitors, dyes. These materials enter the feed throat at the rear of the barrel and then contact the auger.
We heat thermoplastics to a viscous consistency by the mechanical energy generated by heaters and rotating screws. Temperature conditions of medical extrusion are tightly control. Uneven heating and overheating is not good to allow. This is fraught with degradation of the polymer structure.
If too much heat heats up due to friction and pressure inside the cylinder, the cooling fans are turned on.
Further, the viscous mass passes through a mesh filter. This step is necessary to remove the smallest dirt. Then the melt is injected into a die to give a predetermined shape, and the semi-finished or finished product is left to cool.
To avoid distortion of the surface during the hardening process, they are responsible for the choice of cooling technologies. The products places under a stream of cold air, pulled through a water bath or special rolls.
Extrusion benefits
The technology has undeniable advantages:
- Automation. Processes can be automated as much as possible. The absence of a human factor eliminates the risk of defects in the produced batches during continuous production in a 24/7 format.
- Possibility of revision. Parts come out of the extruder warm. Moreover, it allows for the necessary revision and adjustments to the geometric shape with little time and labor.
- High-speed stamping. Large orders for the supply of extrudates come out in a short time. In addition, the punching speed on thermoplastic forming machines is fast.
What products are created using medical extrusion technique?
Modern and functional equipment for medical extrusion of acetal, polyethylene, polycarbonate, nylon, PVC, etc. installs in the shops of the production company .
Furthermore, it is used for the production of profiles of various complexities:
- garden irrigation hoses
- rods
- water pipes
- Packaging films, sheets.
The products meet strict quality standards and are durable. Extruders are also good to process plastic waste. Subsequently, they are good to pre-store, crushed and cleaned from impurities. If recycled plastics have a low viscosity and high elasticity values, they go into a combination extruder. Similarly, in the screw part comes with the disk part.
Extrusion molds are manufactured in four stages, they are as follows:
Design of a product, first carried out in a sketch-drawing view, and then by means of a three-dimensional model created on a computer. Its creation is a key stage in the manufacture of a mold. Since it is on it that the customer, working together with the designers, is able to make the necessary adjustments to its appearance;
Testing of the finished mold
Modern trends in the production of products and various products bring to the consumer the desire to have a unique product. Subsequently, they come with certain differences and properties that differ from other analogues.
In order to meet the desire of the manufacturer to sell the product, and the user to buy it, you can turn to the medical extrusion manufacture of unique molds. Similarly, you can expect unique design features in them. To achieve these goals, our company can manufacture custom-made molds. In addition, we take into account customer requirement.