There are two templates on top of the injection molding machine, one is not moving, called fixed template; the other one can be moved, called moving template. The mold is fixed on these two templates by screws and pressure plates respectively. When the mold is opened, the moving template of the injection molding machine moves, which drives the mold to open.
After the mold is made, the injection molding is done, and the injection molding machine is put on to start beating the product. However, there are many models of injection molding machines
, each of which has its own parameters. The design of the mold must be able to meet the requirements of the injection molding machine model provided by the customer, otherwise, it will not be produced.
There are many design parameters of the injection molding machine
, the following focuses on several parameters related to the mold.
1. Injection volume
The injection volume is the maximum mass value (or volume value) of melt that can be injected at one time during the production of the injection molding machine
, which represents the maximum injection capacity of this type of injection molding machine. The amount of melt used in a mold should be less than the injection volume of the injection molding machine
. Otherwise, the product will not be satisfied and cannot be produced.
2. Clamping force
The clamping force is the compression force of the injection molding machine
on the template when the mold is closed. The clamping force required for the molded product must be less than the rated clamping force of the selected injection molding machine. Otherwise, the molten glue will easily run away from the parting surface and produce flying edges.
Clamping force = clamping force constant × product projection area, i.e.: P = Kp × s
3. Tie rod spacing
There are four tie rods at the dead center of the fixed and dynamic template of the injection molding machine
, their role is to ensure that the injection molding machine has sufficient strength and rigidity, and is also responsible for sliding the template. However, it tends to limit the mold profile size because the mold is lifted in from the middle of the tie bar when it is installed.
The mold outline size cannot be larger than there for the tie bar spacing at the same time. If one of the mold length sizes exceeds the tie bar spacing, then see if the mold is lifted into the tie bar workshop by rotation, if rotation lifting in is also not possible, then the mold size can only be changed, or the injection molding machine can be replaced.
4. Nozzle size calibration
The injection molding machine
nozzle head is generally spherical, in the selection of the gate sleeve, should make the radius of the sphere of the gate sleeve and the radius of the nozzle sphere coincide. In order to prevent the high-pressure melt from the nozzle and the contact gap of the gate sleeve overflow, the general radius of the ball of the gate sleeve should be more than the nozzle radius, while the small end of the mainstream should also be slightly larger than the size of the nozzle hole so that the nozzle and the gate sleeve alignment is easier.
5. Calibration of fixed ejector device
The classification of the ejector device
(1). Center ejector mechanical ejector
(2). Double-sided mechanical ejector
(3). Center top bar hydraulic ejector and double top bar mechanical ejector on both sides
(4). Center rod hydraulic ejector and other auxiliary cylinders combined action