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[Valve Gate System] & [Spear System]
Precise systems that meet various user needs




Advantages of runnerless molding
Utilize the material to the fullest.
100 % of the material is processed into the product.
No need for secondary processing.
Shorter molding cycle improves profitability.
Stabilize the quality of the product.
Automated molding process contributes to the operation stability.
A difference in Valve Gate System and Spear System
The most difference is gate sealing. Valve gate system open / close the gate by mechanical piston reciprocating motion.On the other hand, Spear system open / close the gate by solidifying / melting the small amount of resin at gate by thermal heat transfer of mold temperature factor and tip heater generation factor.

About the Valve Gate
Mechanical valve gate system activate the valve pin by pneumatic reciprocating motion.
We have full-line valve gate systems including options, with the length of 85- 400mm, gate size of 0.8 - 8.0mm, also in accuracy and function range. Depends on application, valve gate system with tip heater function is available.
Principle and Features of the Valve Gate System
"Topless" structure, -- the gate is cut directly into the cavity in order to the most cooling.With a double heater system (the probe has separate heaters for a tip and a body), the tip heater synchronizes the molding cycle to employ the intermittent heating method. This system also facilitates the molding of the crystalline resins.
Overall structure of the Valve Gate System
The system consists of valve gates, manifold (assembled inside the mold), temperature controller, air controller and air source in the factory to activate the valve pins.
Cross -section of the Valve Tip
With Tip heater (Valve pin forward) Without Tip heater (Valve pin retracted)
About the Spear
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 the Spear System
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 the Spear System
The spear system consists of a spear (embedded into the die),
a manifold, and a controller for output (temperature) control.
Cross -section of the Spear Tip

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