1. The unbalanced force of the movable components and s […]
1. The unbalanced force of the movable components and sliding cores in the mold will cause flash. 2. The parallelism between the adjusting head and the diode is not enough or the pressure of the adjusting system is too large. 3. The injection volume set by the barrel is insufficient, that is, if the buffer pad is too small, the injection time will be too long and the injection time will be too small, resulting in flash or dissatisfaction of the parts.
What is a fly edge? Flash, also known as overflow, burr, burr, etc., mostly occurs at the opening and closing positions of the mold, such as the parting surface of the movable mold and the static mold, the sliding part of the slider, the absolute gap of the insert, and the hole of the ejector. etc., flash is largely due to the failure of the clamping force of the mold or machine. Basic reason: From the perspective of plastics, flash is caused by the pressure in the mold cavity exceeding the clamping force, or because the mold parts are damaged.
1. First, analyze the stage in which the flash occurs? (filling stage, or filling stage)
1. First look at the filling process (short-shot products) to determine whether to adopt the staged molding method;
2. Determine in which stage the flash occurs, whether it is the filling stage or the feeding stage.
2. Flash occurs in the filling stage
1. Reason analysis: Since the cavity is not filled during the filling period, it is usually not caused by the pressure in the cavity being too large to exceed the clamping force to expand the mold, so there are possible reasons: During the filling period, the mold parts are deformed; the mold parts Damaged or the parting surface does not fit properly; because the filling speed is too fast or the plastic temperature is too high, the plastic viscosity is too low, and burrs appear in the area where the parting surface does not close tightly.
2. For different reasons, the solutions that can be taken include: modifying the mold structure; reducing the deformation of mold parts by adding gaskets in the center of the template; appropriately slowing down the injection speed or appropriately reducing the temperature of the plastic.