The runner is the conduit for the melt from the sprue to the gate. The cavities should be
placed in the mould in a way which minimizes heat loss and the effect of the runners on
flow, by keeping them as short and free of bends as possible. In cross section, a full
round runner is desirable because it has minimum surface to volume ratio,
and therefore
minimum heat loss and pressure drop. When a runner has to be on one side only of the
parting line, then a trapezoidal shape is preferable to half round.
In multi-cavity systems, in order to fill each cavity as one, the runner and gate
system must be balanced.
placed in the mould in a way which minimizes heat loss and the effect of the runners on
flow, by keeping them as short and free of bends as possible. In cross section, a full
round runner is desirable because it has minimum surface to volume ratio,
and therefore
minimum heat loss and pressure drop. When a runner has to be on one side only of the
parting line, then a trapezoidal shape is preferable to half round.
In multi-cavity systems, in order to fill each cavity as one, the runner and gate
system must be balanced.
0 comments:
Post a Comment