Physical properties of thermoplastic - injection molding machine

Date：2016-07-12 14:12:51

Can the physical characteristics of plastic injection molding machines after the thermoplastic molding their secondary processing into thermoplastics and thermosetting plastics, this process is suitable only for injection molding machines available for secondary processing of thermoplastics, such non-crystalline plastic separator crystallinity categories. Highly crystalline plastic mechanical strength, heat resistance, but poor transparency, a plastic such as polyethylene, polypropylene, polybutene-1, poly-4-methylpentene-1, polyoxymethylene, polyamide, polyester, polyvinylidene chloride, fluorine plastic, chlorinated polyether. Non-crystalline plastic mechanical strength is poor crystalline plastic, but the heat resistance and transparency, this kind of plastic polyvinyl chloride, polystyrene, ABS, PMMA, polycarbonate, polyphenylene oxide, polysulfone and the like.

Different types of plastic, although having some similarities, but personality differences, be sure to do the proper selection of products or aids simulation time can produce compliant products. The temperature of the distillation column by gasoline gasoline temperature adjustment control back flow display by the rotameter. Light diesel gasoline distillation bottoms.

Injection molding machine thermoforming mold thermoplastic molding plaster molds and tin mold needs. Only the transition plaster mold is a mold, the final mold is manufactured of tin.

Because gypsum hemihydrate and water after water into gypsum (CaSOO), gypsum plaster water solubility than half a much lower solubility, gypsum constantly condense, and hemihydrate gypsum continues to dissolve, eventually all turned into gypsum, in the process of change, all the excess water to evaporate. Because the condensation was gypsum volume increased by 1%, so with plaster made of male and female mold, the inner and outer surface smooth, easy to crack tin mold.

Tin melting point of 231.85 ℃, ordinary tin ingots in the crucible of iron melts very easily, and most of thermoformed plastic optimum molding temperature of 120 ~ 220 ℃, so the male and female molds made of tin with a qualified majority of the heat molded plastic processing, for polysilicate, nylon, oriented polyester, polysulfone plastic, optimum molding temperature exceeds 231 ℃, is available, lead, tin, antimony alloy (80% lead, 10% tin, antimony 10% ) made mold forming. Consider shrinkage plastic injection molding machine, the design of the die size to be bigger, so that the final size made accurate parts.

Colored plastic injection molding machine in order to make plastic products with a desired color can be added organic dyes or inorganic pigments in plastics, the former mostly with good miscible resin suitable for transparent products manufactured; the latter in the resin dispersion very good, the system is suitable for transparent products.

Commonly used organic dyes are: 1) azo dyes (including insoluble and poorly soluble), such as aniline yellow, light yellow, golden red C, Li Rubine; 2) phthalocyanine pigments such as sodium Costello Blue Mongolia , Mona Los Tello green.

Commonly used inorganic pigments are: 1) class chrome yellow, the color with the mixture in an amount depending, PbCrO higher the content of the deeper the color, there are lemon yellow, orange chrome yellow and red chrome molybdenum; 2) cadmium pigments cadmium yellow, cadmium red, cadmium selenide; 3) iron oxide red iron oxide, iron oxide yellow, iron oxide black; 4) class titanium dioxide, barium titanium white, titanium white calcium; 5) carbon black. Above dyes and pigments are easy to buy.

The method of plastic mixed colors, with red, yellow and blue as the primary color, with a group called the secondary color hue to another color, other colors redistributed between the secondary colors called tertiary colors.

Various components with different content in plastics, color hue, lightness and purity are also different. For example: secondary colors: red + yellow = orange red apricot red + blue = purple Qinglian color dark pink yellow + blue = green grass green sky blue light color green emerald three color: orange + purple = brown, purple + green + orange = = gray olive green color, blue + yellow + red = brown. In order to improve the plastic and the filler imparting new properties to plastics, usually filling to a powder in a plastic or fibrous filler. Plus plastic clay, mica, asbestos, talc, etc., can improve the rigidity of the plastic, temperature resistance; plastic clay was added after the sintering can be improved insulation; plastic paint can be increased by adding wood flour affinity; plastics Carbon Black can improve the aging properties of plastic; plastic plus copper, aluminum can improve the thermal and electrical conductivity.

Injection molding machine production apparatus of the present process of self-made culverts induction furnace, induction furnace is made based on the principle of electromagnetic induction. Furnace surface is bounded to the heating coil is placed in the furnace core culverts below the surface to be heated tin mold placed over the surface of the furnace. Furnace surface is non-permeable sheet (asbestos or ceramic plate). In a multi-strand copper wire wound heater wire to circle through frequency or high frequency alternating current. When the furnace is not placed face to be heated tin mold, the cooking surface side alternating magnetic field of the magnetic circuit is substantially air magnetic resistance greatly. At this point only a small heating coil in the no-load current. When tin mold to be heated placed on the induction furnace, most of the air had been replaced by a soft magnetic iron magnetic circuit reluctance is reduced, an alternating magnetic field greatly enhanced.

Alternating magnetic field to generate a lot of eddy currents die tin, tin obtained heat mode, temperature rise. Make melt molding plastic injection molding machine. The size of the induction furnace power depends on the size and processing aids may be ,, generally designed to 1kW and 2kW two, the power supply system can be designed as a single-phase or three-phase type two kinds.

The production process for the production of a Fresnel lens as an example. Fresnel lens is an optical element having a stepped surface. Adjacent ladder smaller the pitch, the more accurately meet the conditions reduce the residual aberrations at a smaller lens thickness. Stepped up to the smallest pitch 0.05mm, the ladder can be concentric, spiral or parallel grooves. The first two cases are part of a stepped cone or a sphere. Case 3 is a planar or cylindrical portion.

Plastic Fresnel lens made of poly methyl methacrylate (PMMA).

1) Select the flatness of the glass piece is placed on the platform, the Fresnel lens mold or wood stick to the original flat glass, cardboard and used to do a paper circle around.

2) with a camel hair brush to remove dust on the Fresnel lens ring, and in its coat of thick soapy water.

3) The humidity adjusted too uniform hemihydrate gypsum poured circle paper, dried, torn paper circle Serve plaster mold nightside.

4) on the plaster mold nightside slightly trimmed, coated with thick plaster male mold translated into soapy water.

5) the plaster male mold kerosene smoked black circle around on paper, translated into tin die.

6) The colorless, transparent plastic granular fill in the blank die in tin, in the induction furnace pressure to a flat stainless steel plate, adjusting the current heating, which is formed into a Fresnel lens on its surface.

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