What is moldflow analysis? Mold flow analysis (or MFA) uses software to create a simulation of plastic flow, allowing manufacturers to enhance the design of their mold through a flow analysis of injection molds and create a better product.
By conducting mold flow analysis, manufacturers can get a glimpse into how the material they are using will fill the cavity of a mold, and spot possible problems. Creating a virtual version with mold flow analysis software of the mold before the physical cutting begins allows you to make changes and save on production costs.
When should manufacturers use mold flow analysis?
These factors will help determine whether MFA is necessary for an application:
Tolerance requirements – Products with tighter tolerances can benefit from MFA before tooling to make sure you can meet the specifications for tooling design and materials.
Product geometry – A mold with a more complex shape will likely benefit from mold flow analysis because the flow is less predictable than with a simpler shape.
The scope of the project – There’s a cost associated with conducting mold flow analysis. The scope of the project should be wide enough to justify spending the money and manpower connected to an MFA.
The benefits of using mold flow analysis include:
It allows you to resolve wall thickness issues.
MFA lets you fill cavities in molds with consistency.
You can unearth faults in design geometry, and avoid expensive tooling errors. It also gives you more support if you need to make a case for design changes to your client.
You’ll improve manufacturability, improve quality and efficiency and reduce time to market.
Mold flow analysis lets you uncover visual defects such as air traps, weld lines, and sink marks, and allows you to optimize gate location.
Another key benefit is using the program to predict generalized molding parameters allowing for efficient set-up during the trial phase
a mold flow analysis helps manufacturers understand and predict the pattern of the fill. In order to avoid cases where the molten resin might freeze prematurely prior to reaching the mold cavities, manufacturers can make adjustments to the shot speed, wall thickness, or even the type of resin used for the job.
Some people may have the misunderstanding that injection molding is a simple process. First, pellets of raw resin materials are placed into the machine before passing through heat chambers where these pellets are molten. After this, the molten resin is directly injected into the mold, where the resin fills all the cavities and adopts the desired shape. The resulting finished product will need only be ejected through a hydraulic clamping mechanism that’s built into the machine, without any need for post-processing.
Although the above situation is ideal, injection molding processes rarely transpire in this manner. This is due to the number of issues that can occur, regarding mold wall thickness, injection speed, and pressure. so moldflow analysis is very important
In injection molds, the runner is considered to be one of the most important components. As the name suggests, this is the part of the mold wherein the plastic material or resin “runs through” or passes through when it is already flowing into the mold. Runners are already pre-cut into the mold itself and can affect how well the molten resin reacts to changes in temperature, pressure, injection molding speed, and the like. so you need moldflow analysis
Manufacturing assembly parts and components with plastic demands injection mold companies to understand the rate of shrinkage of each resin they work with. Generally, all plastics that undergo variable temperature changes — i.e. from exposure to extreme heat and then rapid cooling.
Keeping this in mind, manufacturers understand that the shrinkage usually takes place during the cooling stage. As the product is allowed to be stored or distributed for end use, they also have to anticipate the rate at which the finished plastic part can further shrink — which could affect its in-service quality.
Likewise, mold flow analysis provides injection molders with a better understanding of the shrinkage rate. Software can be used to determine shrinkage rate for all kinds of plastics, be it thermoplastics or thermosets, depending on the raw material used. Combined with this, the manufacturer may also choose, depending on a chart, on a different resin type that they could use (preferably one that doesn’t shrink rapidly). Having alternatives regarding the type of raw material is beneficial for both client and customer, as it can drastically improve product tolerances.
you’ve learned about some of the most crucial benefits of mold flow analysis for clients and businesses that provide prototyping services in China, or any other location. With this tool, injection molding firms are essentially given a birds-eye view of every factor that can affect the injection molding process. With this knowledge, they can use the tool to identify any visual defects or impairments in the product, allowing them to strategize on changes they can make to improve the molded plastic.
Moldflow analysis allows clients to set expectations regarding their mold and at the same time, enables injection molding companies to anticipate how well the entire process transpires. With this key pre-injection molding stage, companies or clients can better understand how they can optimize the runner system, adjust the fill pattern, raw materials, and identify any other injection molding-related defects.
As much as possible, injection molders need to have an optimal lead time not only to satisfy their customers, but also accommodate high-volume market distribution of crucial plastic assembly parts. Several factors also affect the lead time. For example, the presence of injection molding defects can increase this process, which can delay the distribution stage.
Having said that, a mold flow analysis tool is also influential in reducing the lead time for all injection molding activities. By being able to identify potential defects and issues early on, even prior to injection molding, they can reduce any post-processing activities. This greatly reduces the lead time and overall leads to better manufacturing outcomes.
With a mold flow analysis tool or software, manufacturers can therefore get a better sense of where the runners should be placed within the mold. Various situations can take place simply depending on runner positioning. For example, the runners can lead to uneven resins flows, especially in a multi-cavity or a high-cavitation mold. However, when the behavior of the runners is viewed through an flow analysis software, adjustments can be made in order to make the runners more geometrically balanced throughout the mold system. This will ultimately lead to reduced internal stresses and consistent flow lengths to each cavity present in the mold.
Before undertaking any injection-molding or prototyping-related project, it’s important not to overlook one of the most crucial phases — mold flow analysis. Many injection molding companies or businesses that provided prototyping services in China, for example, have understood the benefits of mold flow analysis. By undertaking this, manufacturers can predict product outcomes regarding quality and functionality. As injection molding depends on the quality of the mold, tool, runner, gate system, resin, injection speed, and temperature, mold flow analysis is an important primary stage.
Without any tooling or molding necessary, you can answer all the what-if questions ahead of time. Mold flow analysis can point out many concerns or production factors, including:
Material selection issues
Thickness/thinness problems
Structural concerns
Weld line controls
Residual or structural stress issues
Filling concerns
Product function requirements
Sink or appearance problems, and more
You have all the information and answers to make the most optimal choices in injection molds and tooling to create the perfect product. Mold flow analysis can show you everything you need:
The optimal gate locations
Balanced filling and packing
Cavity layout
Mitigation of short-shot molding issues
Optimal injection mold materials
Prototype and production tooling
The best cooling layouts
Structural and thermal analyses for tool life
Core pull/deflection issues
Reasons for tool failures
Engineering calculations of pressure or force necessary for each part
Etc…
You’re now able to test out different materials and designs without building any prototype parts or tools. You can get virtual parts with a simulation as well, so you can have full process simulation with minimal upfront investment.
With mold flow analyses, you can make immediate, informed decisions. These decisions can impact multiple areas of the process including:
Product design
Material and process selection
Tooling
And everything else that is central to your production process
There’s no trial and error involved; there are just proven scientific engineering answers from art to part.
Plastic parts can be optimized for exact machine specification, cycle time, cooling, DOE, and more, without reducing production time or putting any tools on molding machines; this can help improve your bottom-line profit.
You can select the right source with expertise and practical experience for simulation, design, tooling, and molding. Otherwise, you would be spending money on analysis costs, as well as all tooling and molding issues, without obtaining any of the savings from upfront process simulation.
The predictive process of mold flow analysis can uncover design issues, save resources, provide for preemptive correction, and speed up overall cycle time and present your business with an abundance of benefits.
Mold flow analyses can optimize your overall cycle time by up to 10-30%. That reduction percentage on just one part can cancel out the cost of a complete flow analysis of multiple molded parts!