Cycle Time should be as short as possible without compromising product quality. The cycle time includes the following phases: injection time, holding time, plasticizing time, cooling time, ejection time, and low-pressure clamping time. Additionally, the speed of mold opening, clamping, and ejection also relate to time factors.

1. Injection Time

This includes holding time. Generally, a longer injection time results in fuller parts. However, while pursuing quality, production efficiency must also be considered. Moreover, excessively long injection times can lead to overpacking, which may cause issues such as parts sticking in the mold, ejection deformation, or oversized dimensions. Therefore, when setting the injection time, all factors should be considered, and the time should be minimized as much as possible while meeting quality requirements.

2. Plasticizing Time

This depends on the screw rotation speed and backpressure settings. However, one key principle is that the plasticizing time must always be shorter than the cooling time.

3. Cooling Time

The cooling time directly affects the overall cycle time. Longer cooling times lead to longer cycle times and lower production efficiency. Therefore, when setting high-pressure cooling time, it should be as short as possible, provided that part formation is smooth and no issues such as deformation occur.

4. Ejection Time

Ejection time should generally be coordinated with robotic handling. In fully automated production using robots, the ejection dwell time is typically set to 1.5–2 seconds. In semi-automatic production, if retracting the ejector pins too early causes parts to fall or get stuck, the dwell time should be extended to around 5 seconds.

5. Low-Pressure Protection Time

This plays a crucial role in protecting both personnel and the mold. By properly adjusting the low-pressure position and pressure, the low-pressure protection time should be set between 1–3 seconds. A shorter protection time reduces the risk of potential damage.