Figure 2: 2 Plate Mold vs 3 Plate Mold
In many industries, including automotive and aerospace manufacturing, parts must be produced with high accuracy and in large quantities, which makes the choice of the right mold type very important. When creating detailed parts or large numbers of similar parts, the decision to go with 2 plate molds or 3 plate molds can vary greatly.
What will you learn in this blog post?
This blog post will discuss some crucial differences between two-plate and three-plate molds while choosing a mold design. At the end of the discussion, you will be able to conclude which mold design is most suitable for use. So keep on reading.
What is a 2 Plate Mold, And How Does It Work?
Figure 2: 2 Plate Mold
A two-plate mold is one of the simplest and inexpensive molds widely used to create essential plastic components. It has two main components: a cavity and a core split along the parting line. The mold opens in a single operation, while the runner and gate are located at the mid-split line. This configuration lets the runner be taken off along with the molded part; however, the process of removing the runner from the final product remains.
In practice, the mold’s design allows the runner and the ejected part to be located on the same side when molding is being done. When the mold is opened, the side of the mold with the ejection system facility throws the product away from the mold. However, two-plate molds are effective and cost-friendly, though they are less appropriate for creating intricate and accurate components than three-plate molds.
Advantages of 2 plate mold
Using a 2 plate mold offers several distinct advantages:
- Versatility: Two-plate molds can also be created to accommodate smaller sizes and shapes of the part and, therefore, can be used to prototype and produce parts. This makes them suitable for a broad range of projects and quite versatile.
- Cost-Effectiveness: The construction of a two-plate mold is quite basic, which means that initial costs are not too high and general maintenance costs are low. These molds are usually cheaper to construct and manage than multi-plate molds.
- Shorter Cycle Times: The cycle time for two-plate molds is generally lower than for three-plate molds since the B plate does not need to be turned around the part. This leads to shortened production cycles.
- Adaptability: Simple mold use in two plates is ideal with extensive employment of small parts with few or no undercuts or complicated sections. The simplicity of design also implies that it is easier to adapt the mold for new designs or changes in making them.
- Simplified Ejection System: The ejection system of two-plate molds is relatively simple because components can quickly be ejected from the mold.
Disadvantages of 2 Plate Mold
While two-plate molds have many advantages, they also come with some drawbacks:
Flash Issues: If the mold fit is not precise and there are multiple cavities, over-pressure at the parting line can lead to flash formation.
Additional Operations: Removing the core means additional sequence time in a product’s development cycle, and costs can also rise, especially where the core is complex.
Shorter Lifespan: Due to the relatively rare use of the layer of nanotubes, customers get a product with a simpler design that lasts fewer uses before it has to be replaced.
Design Limitations: Two-plate molds are not ideal for making parts containing undercuts or other intricate shapes, as the separation is in only one plane.
Gate Placement Constraints: Usually, it is located in one gate place, and the design is minimal.
Cooling Control: The cooling time must be strictly regulated so that the properties of the final product do not differ so much.
High Cavitation Challenges: This is unsuitable for applications requiring high cavity pressure since the movement of the B plate will not allow for an increase in the production rate.
Are you searching for injection molding vs. compression molding, click here to read!
What is a 3 Plate Mold, And How Does It Work?
A 3-plate mold has one more runner plate than a 2-plate mold, which allows for more possibilities for placing the runner and gate. This added plate helps keep the runner separate and allows for its adjustment so the runner and gate can be put precisely where they are most helpful. The mold functions in two ways: increasing the accuracy of high-quality parts.
In a three plate mold, the core is joined to the cavity until the second stage, where there is the stripper plate to remove the molded part from the gate material. The mold design includes two separation lines and three opening sequences: One is for the runner, the other is for the product, and the last is for the runner stripper plate. This arrangement ensures excellent control of the injection, cooling, and removal of components, thus making it the most appropriate for producing intricate parts.
Advantages of 3 Plate Mold
Using a three-plate mold offers several notable advantages
Using a three-plate mold offers several notable advantages: Using a three-plate mold offers several notable advantages:
- Easy Gate Removal: The three-plate mold stripper plates are unique in their ability to automatically eject runners and gates in the finished parts. Thus, there is no need to require extra hand work.
- Enhanced Design Flexibility: The flexibility of gates placed on the top or bottom surfaces increases the possibility of achieving the best finish and finer features on the part.
- Consistent Flow: Reduced material viscosity also minimizes short shots since the actual shot is more prone to fill the mold cavity efficiently.
Disadvantages of 3 Plate Mold
There are several drawbacks to using a three-plate mold:
- Higher Costs: A three-plate mold is more costly than a two-plate mold, involving higher machining charges, greater mould weight, and time consumption.
- Resin Waste: Longer runners can create more waste resin, which in turn will adversely impact material utilization.
- Complex Design: Three-plate molds are more circurite in design than two-plate molds because of the intricacy involved in the planning process and the material’s design.
2 Plate Mold Vs 3 Plate Mold
| Aspect | 2 Plate Mold | 3 Plate Mold |
| Structure | Consists of two main parts: the A-side (cavity) and the B-side (core). | Consists of three main parts: A-side (cavity), B-side (core), and a third plate (runner plate). |
| Runner System | Typically has a simpler runner system, with the runner and gate located in the parting line. | Features a more complex runner system with runners on one plate and gates on another, allowing for more flexibility in gate location. |
| Gate Location | Limited to the parting line, which might lead to less optimal placement for part quality. | Allows more flexibility in gate location, which can improve the quality and appearance of the part. |
| Cost | Generally less expensive to design and manufacture. | Typically more expensive due to the additional components and complexity. |
| Ease of Maintenance | Easier to maintain due to fewer components. | More complex and therefore more challenging to maintain. |
| Ejection System | Simplified ejection system. | More complex ejection system that may require additional mechanisms. |
| Applications | Suitable for simpler parts where gate placement is less critical. | Ideal for parts that require complex gating and higher quality finishes. |
| Cycle Time | Generally shorter cycle times because of the simpler demolding process. | Potentially longer cycle times due to the additional plate movement and gating complexity. |
| Material Waste | Potentially more material waste due to the position of the runner and gate. | Can be optimized to reduce material waste by better positioning gates and runners. |
| Part Quality | May have limitations in ensuring uniform filling and minimizing defects. | Better control over filling and quality, which can lead to higher precision parts. |
| Use Case | Ideal for large, simple, and less intricate parts. | Preferable for smaller, intricate, and high precision parts where gate positioning is critical. |
Thus, the critical marks of the difference between 2 plate and 3 plate molds reside fully in their structure and applied purpose. A 2 plate mold has the runner as a part of the parting line, and the mold’s ejector system takes out both the part and the runner. This design is relatively simpler and cheaper than the other evolutionary designs.
Complicating the earlier model involves the inclusion of an additional runner plate on the 3-plate mold. It is discharged individually by a pusher, and the general design of the mold is more complex and, therefore, more costly and time-consuming to use.
In summary: how to choose
The following things should be considered when choosing between these molds: 3 plate molds provide the required control over the concrete but imply higher costs and manufacturing complexity.
Those people with a molding requirement but less time and a strict budget constraint should get help from Go4mould. We deal with the manufacturing of different kinds of molds and offer injection molding services. Please contact us to learn how we may assist you with your molding requirements.
