The Simple Guide to Injection Molding Gates

Injection molding gates are the openings that allow liquid plastic or metal material to be injected into the mold. It is important to consider the type of part being made to determine the best location and type of gate to use. Additionally, the size of the gate is equally important, as it can affect the quality of the finished workpiece.

Types of Injection Molding Gates

There are several different types of injection molding gates. You need to have a general understanding of each one to select the right gate for your injection molding services. The type of gate selected also determines whether you can use manual or automated trimming processes.

Manual trimming processes are well-suited for workpieces that need special care and handling or those that are simply too big for automated processes to handle. Manual trimming is also ideal for certain liquid materials that, when hardening, could be damaged from automated processes.

1. Sprue/Direct Injection Gates

These gates are used when you want to manufacture certain types of cylindrical workpieces or workpieces that only have a single cavity for their mold.

2. Sub-Gates

This gate provides flexibility in the placement of the gate on the mold. Sub-gates are typically used along with automated trimming processes.

3. Edge Gates

This type of gate is placed on the side of the mold. It is used when manufacturing flat workpieces, as well as those that are thicker or have multiple cavities.

4. Hot Tip Gates

As the name implies, these gates are placed on the tip or top of the mold. They are often used when producing round or cylinder-shaped workpieces that require uniformity and even flow of the liquid material.

Why Is the Placement of Injection Molding Gates Important?

The placement of injection molding gates is important, as it will affect the flow of materials and the end results. If the gate is placed in the wrong location, it can cause various problems like uneven thicknesses, material shear, and so on.

Ideally, you want to make sure the gate placement is in the location on the mold that will produce the strongest section of the workpiece. For more complex workpieces, you may need multiple gates placed in different locations to ensure precisely filled workpieces.

Furthermore, the placement of the gate will be related to whether you are using manual or automated trimming processes. The gate should not get in the way when you open the mold to remove the workpiece.

Why Use Automated Trimming Processes with Injection Molding Services?

Automated trimming processes eliminate the need for a machine operator to open and remove the workpiece from the mold. It also eliminates the need to trim off excess material from the part using secondary and finishing operations.

With automated trimming processes, after the workpiece is produced and cools, the machine automatically trims off any excess material left in the location where the gates are located. Additionally, it helps reduce the number of secondary and finishing operations required, which could lower production costs. Automated trimming processes, however, are not always appropriate or the best solution, depending on the type of injection molding gates being used and the workpieces being produced.

For further information about injection molding gates, designing injection molds with proper gate placement, injection molding services, and custom machining services, please feel free to contact Laszeray Technology, LLC at 440-582-8430 today!