Belépés Facebookkal
[ Ablak bezárása ]
Jug Mould
The plastic can be pure resin or a mixture with various additives. The resin acts as a binder. The purpose of adding additives is to improve the physical and mechanical properties of pure resin, improve processing performance or to save resin.
Therefore, the most basic Plastic medical mould physical and chemical properties of plastics are determined by the properties of the resin. Resin can be divided into natural resin and artificial resin, the latter is also called synthetic resin.
Resins are all polymers, these polymers have unique molecular internal structure and molecular external structure. The internal structure of the polymer determines the most basic physical and chemical properties of the polymer; the external structure of the polymer determines the processing and physical mechanical properties of the polymer.
Polymers can be divided into non-crystalline (amorphous), semi-crystalline and crystalline according to the structural morphology between the chains after solidification. Therefore, plastics are also divided into amorphous and crystalline types.
When the crystalline plastic is solidified, there is a process of nucleation to crystal grain formation, forming a certain body state. Such as PE, PP, PA, POM, etc. are all crystalline.
When amorphous plastics solidify, the growth process without crystal nuclei and crystal grains is just the "freezing" of free macromolecular chains such as PS, PVC, PMMA, PC, etc.
According to the reflection of its plastics on heat, it can be divided into two types: thermoplastics and thermosetting plastics: Thermoplastics are characterized by being softened by heating and returning to solid state when cooled. This reversible process can be repeated many times. Such as: PS, PVC, PA, PP, POM, etc.; while thermosetting plastics are characterized by being transformed into plastic melts at a certain temperature, but if you continue to increase the temperature and extend the heating time, the inside of the polymer will undergo cross-linking and solidify. It can no longer be softened to the original state by heating, and can not be processed repeatedly. Such as: epoxy, furan, amino, phenolic, etc.
Garbage bin mould
It is a method in which the plastic material is first heated and melted in the heating barrel of the injection molding machine, and then the melt is pushed into the cavity of the closed mold by the reciprocating screw.
It can not only produce high-precision, high-quality products under high productivity,Bucket mould but also has a wide variety of plastics that can be processed, a large output (about 1/3 of the total amount of plastic) and a wide range of uses. Therefore, injection molding is an important part of plastic processing One of the molding methods
Extrusion molding
Extrusion is a method in which the plastic is continuously passed through the die in a flowing state by heating and pressing in an extruder.
It is generally used in the molding of plates, pipes, monofilaments, flat wires, films, wire and cable coatings, etc., with a wide range of uses and high yields. Therefore, it is one of the important molding methods in plastics.
Foam molding
It refers to the addition of suitable foaming agents to the foaming materials to produce porous or foamed products. The foamed products have low relative density, high specific strength, low raw material consumption, sound insulation, heat insulation and other volt points. There are PVC, PE and PS etc.
Products include: films, sheets, pipes, and profiles, etc. Foaming can be divided into chemical foaming and physical foaming.
Blow molding
Blowing (expanding film) molding (or hollow blow molding) refers to a molding method in which the hot thermoplastic parison or sheet in a closed mold is inflated into a hollow product by means of fluid (compressed air) pressure.
Plastic containers produced by this method. Such as various bottles, square, round or flat barrels, gasoline tanks, etc. have been widely used, and newly developed various industrial parts and daily products, such as double-walled box-shaped products, L-ring large drums. Stacking boards. Surfboards. Seat backs and desks, as well as front spoilers for automobiles, belt covers, instrument panels, air-conditioning vent pipes, etc., which have been applied in practice and processed materials From daily-use plastics to engineering plastics, blow molding has become one of the important molding methods in plastic processing.
After the general plastics are synthesized, they are all flour-like powders coming out of the synthesis towers of large petrochemical plants, which cannot be used to directly produce products. This is what people often say that the components of fat extracted from tree sap are the same. Plastic medical mould Known as resin powder, this is a pure plastic with poor fluidity, low thermal stability, easy aging and decomposition, and not resistant to environmental aging.
In order to improve the above defects, heat stabilizers, anti-aging agents, anti-ultraviolet agents, plasticizers, etc. are added to the resin powder. After granulation modification, its fluidity is increased, and the resin powder is produced to adapt to various processing techniques. Plastic varieties with special properties and different grades. Therefore, there are many grades of the same type of plastic. According to the processing method, there are injection molding grade, extrusion grade, and blown film grade; according to performance, there are high rigidity, toughened, etc. .
The plastic materials commonly used by medical device manufacturers are plastic particles that can be used directly after modification. For products with special properties that are not available in the market, equipment factories can introduce granulation production lines and process and produce plastic granules through different formulation designs.
Since it is in contact with the liquid medicine or the human body, the basic requirements of medical plastics are chemical stability and biological safety. In simple terms, the components in the plastic material cannot be precipitated into the liquid medicine or the human body, will not cause toxicity and damage to the tissues and organs, and are non-toxic and harmless to the human body. In order to ensure the biological safety of medical plastics, medical plastics usually sold on the market are certified and tested by medical authorities, and users are clearly informed which grades are medical grade.
According to the structure and strength requirements of the equipment products, we choose the appropriate plastic type and the appropriate brand, and determine the material processing technology. These properties include processing performance, mechanical strength, use cost, assembly method, sterilization and so on. The processing properties and physical and chemical properties of several commonly used medical plastics are now introduced.
The plastic can be pure resin or a mixture with various additives. The resin acts as a binder. The purpose of adding additives is to improve the physical and mechanical properties of pure resin, improve processing performance or to save resin.
Therefore, the most basic physical and chemical properties of plastics are determined by the properties of the resin. Resin can be divided into natural resin and artificial resin, the latter is also called synthetic resin.
Resins are all polymers, these polymers have unique molecular internal structure and molecular external structure. The internal structure of the polymer determines the most basic physical and chemical properties of the polymer; the external structure of the polymer determines the processing and physical mechanical properties of the polymer.
Polymers can be divided into non-crystalline (amorphous), semi-crystalline and crystalline according to the structural morphology between the chains after solidification. Therefore, plastics are also divided into amorphous and crystalline types.
When the crystalline plastic is solidified, there is a process of nucleation to crystal grain formation, forming a certain body state. Such as PE, PP, PA, POM, etc. are all crystalline.
When amorphous plastics are solidified, the growth process without crystal nuclei and crystal grains is just the "freezing" of free macromolecular chains such as PS, PVC, PMMA, PC, etc.
According to the reaction of plastics to heat, it can be divided into two types: thermoplastics and thermosetting plastics: Thermoplastics are characterized by being softened by heating, and returning to solid state when cooled. This reversible process can be repeated many times. Such as: PS, PVC, PA, PP, POM, etc.; while thermosetting plastics are characterized by being transformed into plastic melts at a certain temperature, but if the temperature is continued to increase, and the heating time is extended, the inside of the polymer will undergo cross-linking and solidification. It can no longer be softened to the original state by heating, and can not be processed repeatedly. Such as: epoxy, furan, amino, phenolic, etc.
What is the mold used to make a resin table?
1. What is the mold used to make the resin table?
A typical fence structure can be done. Because the river table is mostly in the form of a board surface and not very thick, it can generally be made without any special molds. You can find some pvc boards or other flat boards as frame fences, both are ok. If you use glass plates or metal plates, you can use some mold release materials, such as mold release wax, for smoother demolding.
What is the mold used to make a resin table?
2. What material is used to make resin mold?
A typical resin glue mold is referred to as a glass fiber reinforced plastic mold, or glass fiber mold, which is generally composed of glass fiber and resin hand-laid laminated composite.
The main materials of the resin glue mold are glass fiber, resin glue and mold gel coat. Other materials include some mold release wax, curing agent, polishing wax and so on. Glass fiber has 30g surface mat without alkali, 300g chopped strand mat and 400g gingham cloth. The resin includes vinyl resin or unsaturated resin and epoxy resin, etc. The mold gel coat generally uses vinyl system.
If you want to know the specific mold materials to be used, it is recommended that you contact your local composite material distributor. Generally, they will provide you with a complete list of mold making materials based on your actual situation.
Jug Mould
In the production of die casting, the mold often encounters the defense methods of the pouring system, the overflow system, the runner, the inner gate, and the overflow groove.
1. Pouring system, overflow system
① The diameter of the pressure chamber should be selected according to the required specific pressure and the fullness of the pressure chamber. At the same time, the deviation of the inner diameter of the sprue sleeve should be appropriately enlarged by a few more than the deviation of the pressure chamber diameter, so as to avoid The internal diameter is different from the axis, causing the punch to jam or wear serious problems, and the wall thickness of the crate mould sleeve should not be too thin. The length of the sprue sleeve should generally be less than the ejection lead of the injection punch, so that the paint can escape from the pressure chamber.
② The inner hole of the pressure chamber and the sprue sleeve should be finely ground after heat treatment, and then ground along the axis. The surface roughness is less than or equal to Ra0.2μm.
③ The diverter and the cavity forming the paint have a recessed depth equal to the depth of the runner, and its diameter matches the inner diameter of the sprue sleeve, with a 5° slope along the demolding direction. When a coating-introduction sprue is used, the fullness of the pressure chamber can be increased because the effective length of the pressure chamber is shortened.
2. Requirements for the mold runner
① The entrance of the runner for cold horizontal molds should generally be located at a position above 2/3 of the inner diameter of the upper part of the pressure chamber to prevent the molten metal in the pressure chamber from entering the runner prematurely under the action of gravity and starting to solidify in advance.
② The cross-sectional area of ??the runner should be gradually reduced from the sprue to the inner gate. In order to expand the cross-section, negative pressure will appear when the molten metal flows through, which can easily inhale gas on the parting surface and increase the flow of molten metal. The vortex in the air. Generally, the cross section at the exit is 10-30% smaller than that at the entrance.
③ The runner should have a certain length and depth. The purpose of maintaining a certain length is to stabilize the flow and guide. If the depth is not enough, the molten metal will cool down quickly, and if the depth is too deep, the condensation will be too slow, which will affect the productivity and increase the amount of recycled material.
④ The cross-sectional area of ??the runner should be greater than the cross-sectional area of ??the inner gate to ensure the speed of the molten metal. The cross-sectional area of ??the main runner should be larger than the cross-sectional area of ??each branch runner.
⑤ The two sides of the bottom of the runner should be rounded to avoid early cracks. The two sides can be inclined at about 5°. The surface roughness of the runner part is less than or equal to Ra0.4μm.
3. Inner gate
① The parting surface should not be closed immediately after molten metal is injected into the mold, and the overflow groove and exhaust groove should not impact the core directly. After the molten metal enters the mold, the flow direction is as far as possible along the cast ribs and fins, and fills from the thick wall to the thin wall.
② When selecting the position of the inner gate, make the molten metal flow as short as possible. When using multiple internal gates, it is necessary to prevent several molten metal from converging and impacting each other after entering the mold, resulting in defects such as vortex entrapment and oxidation inclusion.
③ The thickness of the inner gate of the thin-walled parts should be appropriately smaller to ensure the necessary filling speed, and the setting of the inner gate should be easy to cut, and the casting body should not be damaged (eat meat).
4. Overflow tank
① The overflow groove should be easy to remove from the casting, and try not to damage the casting body.
② When opening an exhaust groove on the overflow groove, pay attention to the position of the overflow port to avoid premature blockage of the exhaust groove and make the exhaust groove inoperative.
③ There should not be several overflow openings or a very wide and thick overflow opening on the same overflow groove, so as to prevent the cold liquid, slag, gas, paint, etc. in the molten metal from returning to the cavity from the overflow groove , Resulting in casting defects.
Taizhou Huangyan Jtp Mould Co.,ltd is known as one of the best China Plastic Bucket mould Manufacturers and Plastic Bucket mould factory for plastic household items