Plastic Injection Mold Manufacturing Since 2005

How do you calculate cycle time of injection molding?

Table of Contents

Injection molding is a cyclic process. It is an important measure of the efficiency of the injection molding process, as it can impact the production rate and the overall cost of the parts.

It is a complex process that requires precise timing of several crucial steps. The cycle starts with the storage and feeding of materials into the injector, followed by maintaining injection pressure to form the desired shape.

Cool downtime then allows for adequate hardening before opening and closing injection molds are released from one another, allowing pickup or ejection onto collection trays.

Calculate the total cycle time for injection molding by adding up times from each step. It is essential to determine efficiency and optimize production rate, as well as control costs of parts produced this way.

Cooling and screw metering occur simultaneously, but it’s important to record the longer duration between them in order to get an accurate measure.

How to calculate the cycle time of injection molding?

The timeline for storing and injecting parts has a range of variables to consider, from the properties of polymers and product shape to injection pressure, rate, revolutions, back pressure — even temperature.

While precision is key when it comes to quality requirements like size or appearance; seeking out the shortest time possible within these boundaries should also be taken into account during estimation.

Typically one starts by calculating 65-85% capacity based on plasticizing flow (g/s) capabilities in an injection molding machine.

The injection process typically consists of three segments: slow, fast and then again slow.

To accurately determine the total time for the glue to be injected (T), one should factor in several parameters including its weight at a single product level multiplied by number taken into account as well as the nozzle’s own contribution;

Maximum speed achievable from your injection molding machine and finally base start/stop duration on the screw’s hard work!

These calculations normally vary between 80-200 seconds where 1-2 seconds is the earliest guess or 500-1000 with 3 -4 seconds being closer approximations when looking at holding times elapsed since cavity filling began until it ends.

The key to successful product production lies in striking the right balance between quality and efficiency. Critical here is the cooling time, which must be kept short while still ensuring a high-quality outcome with no shrinkage or other defects.

This process can only be achieved through careful consideration of several factors like the design of injection mold cooling water, wall thickness, material properties, and more – all working together to ensure shorter yet desirable outcomes for end products.

See the table below for cooldown times:

Material termMaterial thickness 1mmMaterial thickness 2mmMaterial thickness 3mmMaterial thickness 4mmMaterial thickness 5mmMaterial thickness 6mm
Soft PVC2.28.920.135.755.880.3
Hard PVC2.710.724.34367.396.8
Cooling time (s)

Accurate injection mold opening and closing times are essential for efficient production operations.

Several aspects of the machine, such as its size and structure, can impact these durations; core-pulling mechanisms (row positions), rack drives for frame movement;

And three plate molds with fine nozzles all contribute to varying time frames depending on tonnage capacity – from 4-8 seconds in 80T200T machines up to 8-15s in 500T1000Ts.

Ejection pick-up speed also varies due to stroke length and automated or manual picking methods.

Automated drop is an efficient and effective method to produce goods quickly, especially when works don’t need a high level of aesthetic appearance or the items are small.

Injecting molds close after the product leaves their range in just 0.5-2 seconds – usually, 3-8 seconds faster than manual labor requires!

What factors can impact the cycle time of an injection molding process?

1. The size and complexity of the molded part

Larger or more complex parts mFaster production times can be achieved by casting smaller or simpler parts, as these require less time to cool and fill the injection mold for a quicker cycle.

2. The material of the injection molded parts

Cycle times can be profoundly impacted by the flow characteristics and cooling rates associated with each material type. Optimizing these factors is essential for efficient operations.

3. The condition of the injection mold

A smooth-running mold is essential for an efficient cycle time. Proper maintenance and precise features lead to faster production, helping minimize downtime and maximize profits.

4. The injection molding machine

The size, capabilities and settings of the injection molding machine all play a crucial role in determining cycle time.

It is essential to regularly measure and log these times in order to identify any potential problems that could arise during the process.

Taking into account details such as material type, clamping force or injection speed can help optimize efficiency while still maintaining quality output – an important factor for success!


Uncovering areas of improvement in the plastic injection molding process can be made easier with the help of careful cycle time calculation.

Keeping track and monitoring this key metric allows for more efficient production rate along with cost-effective measures, enabling businesses to reach their full potential.

Latest Posts
Share on facebook
Share on twitter
Share on linkedin
Share on pinterest

Email: info@zetarmold.com

Or Fill Out The Contact Form Below:

Ask For A Quick Quote

Send drawings and detailed requirements via 


Or Fill Out The Contact Form Below:

Спросите быструю цитату

Мы свяжемся с вами в течение одного рабочего дня, обратите внимание на письмо с суффиксом «xx@zetarmold.com».

Ask For A Quick Quote

Send drawings and detailed requirements via 


Or Fill Out The Contact Form Below:

Ask For A Quick Quote

Send drawings and detailed requirements via 


Or Fill Out The Contact Form Below: