What are pouring runner role and working condition requirements

Functions and roles of gating system, mainly is the injection of molten material from the nozzle, use the shortest possible time, faster velocity, smooth transmission, full of everywhere in the cavity, at the same time to transfer to the injection pressure equilibrium melting mould parts, to ensure smooth molding plastic products.
working conditions of the pouring runner for this requirement is as follows.
1. Each flow in gating system should do good to shorten the distance.
2. For liquid flow channel unobstructed, small flow resistance, temperature drop less loss, but it can't decompose is expected to rise.
3. Discharge of air inside the cavity.
4. Gate residual traces will not affect the appearance.
5。 Melt the front end of the cold material could not enter inside the cavity, avoid affecting product quality.
6。 Each port must have certain taper to facilitate products material handle when stripping away.