Injection molding machine for sale | Do you know the important technical parameters of injection molding machine?
1. Injection volume
It is defined as the maximum weight of PS plastic injected into the air. When the material of plastic products is different from PS, the injection volume is converted to: M = CB / 1.05 (where B is the density of the plastic and C is the injection volume expressed by PS plastic). The total weight of the product should be controlled within 85% of the injection volume, the maximum value should be taken for non crystalline plastics, and the smaller value should be taken for high viscosity plastics.
2. Clamping force
It is defined as the final locking force formed by the template to the mold when the molten material is injected into the mold cavity at the end of mold closing. The clamping force is usually calculated by the product of the average pressure in the cavity and the projected area of the cavity. The average pressure in the cavity is generally 20-40mpa.
3. Injection pressure and injection rate
In the specifications of injection molding machine, injection pressure is the highest pressure in the barrel during injection, not the highest pressure of injection system oil pressure. The relationship between injection pressure and oil pressure is inversely proportional to the ratio of screw cross-sectional area and injection cylinder area.
Injection rate refers to the amount of molten material ejected from the nozzle in unit time, and its theoretical value is the product of the cross-sectional area of the barrel and the velocity.
4. Die thickness and maximum opening stroke
In the specification parameters of injection molding machine, there are usually maximum and minimum mold thickness, which represent the mold thickness of the injection molding machine.
The moving stroke of the injection molding machine is limited, and the required opening distance to take out the parts must be less than the maximum opening stroke of the injection molding machine. For the injection mold with single parting surface, the opening stroke is s > = H1 + H2 + 5 ~ 10 (mm), H1 is the demoulding distance (usually equal to the height of the mold core), H2 is the height of the part (including the gating system). For the three plate injection mold with double parting surface, the opening distance needs to increase the separation distance between the fixed template and the gate plate.
5. Relevant dimensions of die installation part
The length and width of the mold should be compatible with the size of the injection molding machine template and the distance between the pull rods to ensure that the mold can be successfully installed on the template through the distance between the pull rods. When positioning, it should be considered that the center of the main channel of the die coincides with the center line of the barrel nozzle;
The size of the locating ring on the mold should be consistent with the size of the locating hole on the fixed template of the injection molding machine, and the gap fit should be adopted; The spherical radius of the nozzle of the injection molding machine should be consistent with the spherical radius at the beginning of the main runner of the mold; The pin size of the front and back mold should match the screw hole arrangement on the fixed mold of the injection molding machine.
6. Ejection stroke
The ejection stroke should be reasonably selected according to the appearance of the product and the design structure of the mold. Generally, the ejection stroke of the machine is fixed. When ordering the machine, the ejection stroke should be larger, so as to be suitable for more kinds of products.