How to choose the right injection molding machine?(1)

How to choose the right injection molding machine?(1)

1. Select the right model: The model and series are determined by the product and plastic.
Since there are many types of injection machines, it is necessary to correctly determine which injection molding machine or series the product should be produced from at the beginning, such as general thermoplastics or bakelite raw materials or PET raw materials. Color, two-color, multi-color, interlayer or mixed color, etc. In addition, some products require conditions such as high stability (closed loop), high precision, ultra-high rate of fire, high injection pressure, or rapid production (multi-loop), and the appropriate series must also be selected for production.
2. Determine whether the "Large Column Inner Distance", "Mold Thickness", "Mold Minimum Size" and "Die Plate Size" of the machine are appropriate from the mold size to confirm whether the mold can be placed.
The width and height of the mold must be smaller than or at least one side smaller than the inner distance of the large column;
The width and height of the mold should be within the size range of the mold plate;
The thickness of the mold must be between the mold thickness of the injection molding machine;
The width and height of the mold must meet the minimum mold size recommended by the injection molding machine, and it is too small;
3. Determine whether the "mold opening stroke" and "mold stroke" are sufficient for taking out the finished product by the mold and the finished product.
The mold opening stroke must be at least more than twice the height of the finished product in the direction of opening and closing the mold, and the length of the sprue must be included;
The stroke of the supporting mold must be enough to eject the finished product;
4. The "clamping force" tonnage is determined by the product and plastic.
When the raw materials are injected into the mold cavity at high pressure, a mold supporting force will be generated. Therefore, the clamping unit of the injection molding machine must provide enough "clamping force" to prevent the mold from being opened. The calculation of the clamping force requirement is as follows:
Obtain the projected area of ​​the finished product in the direction of the switch mold from the appearance size of the finished product;
Die support force = projected area of ​​the finished product in the direction of the switch mold (cm2) × number of mold cavities × pressure in the mold (kg/cm2);
The pressure inside the mold varies with the raw material, generally 350～400kg/cm2 for raw material;
The clamping force of the machine must be greater than the clamping force, and for the sake of safety, the clamping force of the machine usually needs to be 1.17 times greater than the clamping force;
At this point, the specifications of the clamping unit have been preliminarily determined, and the tonnage of the model has been roughly determined, and then the following steps must be carried out to confirm which injection unit has a screw diameter that meets the requirements.