Following the customer’s needs, the gas-assisted injection molding combined with FLEXflow Technology is the ideal solution to inject the hollow handle of the chainsaw.

The mold is provided with 2 hot runner needle valve nozzles of the MA series with a conical seal. They are designed for medium shot weights and optimized for the polymer used in this special application: PA6-GF30 %. The servo-driven valve gate solution allows to control the stroke and force of each individual pin independently during the opening and closing phases. This ensures an optimum mold-filling process.

With the gas-assisted injection molding technology, nitrogen is subsequently injected under high pressure into the injected melt, which is consequently pushed against the cavity wall. FLEXflow solution can overcome one of the main issues of the pneumatic system: it allows for the perfect closing of the valve pin and it avoids the gas back up into the manifold.

Using the near perfect repeatability of the servo valve gate to control the process at each gate independently allows for maximizing the weight reduction benefit of the gas assist technology while simultaneously increasing yield by reducing the scrap rate.

The result is a hollow and thus lightweight injection-molded part. It also boasts high bend strength and a streak-free Class A surface without flow marks and other surface defects.

The system is composed by 2 FLEXflow drops Ma Series with conical valve gate. Each valve gate pin is activated by FLEXflow, our servo driven valve gate technology.

Read the full Case Study on Plastics Machinery Magazine!