The common runner system, also known as the runner syst […]
The common runner system, also known as the runner system or gating system, is the necessary passage for molten plastic from the injection nozzle of the injection machine to the cavity. Its function is to smoothly introduce molten plastic from the nozzle of the injection moulding machine into the cavity of the Dustbin Mould and to transfer the injection pressure and the holding pressure to various parts of the plastic products during the filling and solidification of the melt. The runner system comprises the main runner, a shunt runner and a gate. Let's take a look at the basic principles of the design of the dustbin mould runner.
For multi-cavity layout, the balanced runner should be used as far as possible, i.e. the gate position of each cavity should be the same and the runner length should be the same.
1. Heat and pressure losses should be small, the flow passage should be shortened as much as possible, the section size should be as large as possible, bending should be reduced as much as possible, and the surface roughness should be low, but the problem of small material consumption should also be considered.
2. The gating system should be able to capture the "cold material" with a lower temperature to prevent it from entering the cavity and affecting the quality of plastic parts.
3. The gating system should be able to smoothly guide the plastic melt to fill all corners of the mould cavity so that the mould cavity gas can be smoothly discharged.
4. The gating system shall be able to prevent shrinkage, deformation, dimensional deviation and other defects of plastic parts.
5. The gate should be cut off conveniently without affecting the appearance of the product.
6. Improve production efficiency, reduce post-processing of plastic parts as much as possible, and shorten forming cycle.