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The best way to choose a vertical injection molding machine

In General, injection molding industry for many years most of the customers have the ability to judge for themselves and choose the appropriate injection molding machines to produce. 
However, in some situations, clients might require manufacturers to help to decide which specification of injection molding machines, customers may only samples of a product or idea, and then asked whether machine manufacturers capable of producing or which model is better suited. In addition, some special products, you may need a special mix device such as the accumulator, closed-loop, injection-compression can be produced more efficiently. Therefore, how to determine the appropriate injection molding machines to produce, is an extremely important issue. Provide the following information to readers.
Usually impact shot out machine select of important factors include mold, and products, and plastic, and forming requirements,, so, in for select Qian must first collection or has following information: mold size (width, and height, and thickness), and weight, and special design,; using plastic of type and the number (single raw materials or multiple plastic); injection finished of appearance size (long, and wide, and high, and thickness), and weight,; forming requirements, as quality conditions, and production speed,.
After obtaining the above information, you can follow these steps to choose the suitable injection machine:
1, right: determined by the products and plastic models and series.
Due to the injection machine very many kinds, so should start to correctly judge the product by what kind of injection molding machines, which series or production, such as thermoplastic plastics or wood raw material or PET raw materials, is monochrome, color and more color, laminated or process color. In addition, some products require a high stability (closed-loop), high precision, high speed, high pressure or rapid production (loop) and other conditions, must also select the appropriate series production.
2, lock up: determined by the product and plastic "clamping force" tonnage.
When raw materials to high pressure injection die cavity inside a hold mode when the power clamping unit of injection molding machine must therefore provide sufficient "clamping" dies from being open. Calculation of clamping force requirements are as follows:
Products dimensions to find the products in the switching direction of projection area;
Hold mode = finished switching direction of projection surface area (cm2) × die cavity ×-mould pressures (kg/cm2);
Internal mould pressure different depending on raw materials, raw materials generally take 350~400kg/cm2;
Machine the clamping force required is greater than the last model, and just to be sure, machine the clamping force usually needs to be greater than hang on mode power 1.17 times more than double.
Decisions so far have been preliminary specification of mould clamping unit and can generally determine machine tonnage, you must then perform the following steps to confirm which comparison of screw diameter injection unit required to meet.
3, put it down: by the die size to determine the machine "column from", "mould thickness", "die minimum size" and "mould plate size" is appropriate, to verify that mold can lay down.
Mould width and height required less than or at least less than the large column from within; best height and width of the mold in the die plate dimensions within the boundaries of mold thickness to be between injection molding machine mold thickness between mould width and height required to meet the recommended minimum die size injection molding machine, not too small.
4, produced from molds and finished product to determine "opening stroke" and "holds the stroke" enough to take out.
Opening stroke required is greater than the height of the finished products in the switching direction at least twice or more, and the same sprue (Sprue) the length of the scroll of stroke required adequate finished product the top.
5, full shot: by product weight and number of die cavity judgement needed "shot" and select the appropriate "screw diameter".
Calculating the number of die cavity to be considered finished weight (a die-a few points);
For stability reasons, injection quantity for the finished weight of 1.35 times more than double the weight required for projected volume of finished product within 75%.
6, shot it well: made of plastic to determine "screw the compression ratio" and "injection pressure" condition.
Some engineering plastics require high injection pressure and suitable screw compression ratio design, better results, so in order to make the finished shot was better, when choosing a screw will also need to consider the needs of shooting and compression problems.
In General, the smaller diameter of the screw higher injection pressure is available.
7, shooting fast and "shoot speed" to confirm.
Some products needs to stabilize its rapid-fire overhead rate, such as thin type of product, in this case, you may need to confirm the adequacy of injection rate and the rate of fire of a machine, will there be a match accumulator, a closed-loop control devices. In General, under the same conditions, provides high radiation pressure screw is usually relatively low rate of fire, on the other hand, can provide a shot in the lower pressure screw is usually higher rate of fire. Therefore, when choosing a screw diameter, injection, injection pressure and injection rate (projected) that need to cross considerations and choices.
In addition, the circuit design can be used to synchronize compound action to shorten the time.


 

However, "there is no free lunch", performance upgrade and modification of the machine can increase the productivity, of course, but often increased the cost of investment and operation costs, therefore, benefit assessment should think carefully before investing to measure in order to have maximum benefits to the most appropriate model.