Seiki – Spear System
The spear has a double heater structure consisting of a tip heater and a body heater.
The spear tip has been modified to directly heat itself.
There are a large variety of spears available to accommodate different resin types and applications.
Principle and Features of Spear System
Spear probe has long service life because of its thermal valve principle having no sliding part.
The resin at the sprue and runner is kept molten to maintain constant fluidity. Depending on the temperature of the gate land and a die, a very small amount of the resin solidifies along with the resin inside of the cavity.
After the molded product is removed, the spear tip is heated up to instantly melt the solidified resin at the gate land just before the next injection.
Overall structure of Spear System
Spear System consists of a spear (embedded into the die), a manifold, and a controller for output (temperature) control.
Spear System lineup
- Series SPT
- The newly-developed external heating topless probe is equipped with a tip heater.
- It is best suited for molding high-function plastics for extremely small mechanical parts.
- It can be used for multiple cavity moulds as well, taking advantage of its compactness of minimum 7mm pitch.
- Unlike a conventional block method, gate layout can be arranged flexibly.
- Applicable to small parts molding, as small as using a 15t machine.
- Minimum resin content and first-in-first-out flow path prevent the resins from deterioration and contamination.
- Tip replacement between several types is available to suit to the resin.
- Series ESXL
- Specifically for side gating.
- Best suited to medical parts.