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Archive for the ‘Injection Molding’ Category

Validated Injection Molding : Meeting Design Specs, Every Time

Posted on: April 19th, 2017 by The Technology House

When it comes to manufacturing parts, there are many methods to choose from. For example, injection molding is used to make everything from bottle caps to MRI coils. The process produces end-use ready results for applications in many industries. There are applications, such as medical devices or aerospace that require an even higher degree of accuracy and trust for a consistent, molded part. For these situations, Sea Air Space Machining and Molding (SAS) offers validated injection molding. Validation involves making sure that the machines used, materials employed, and manufacturing processes followed meet stringent accuracy and repeatability standards. While SAS offers a complimentary design review on all orders, validated injection molding involves far deeper design verification and customer collaboration. It starts with working closely with the customer to make a plan. SAS has a standard process and then tailors these steps to the customer’s unique needs. This collaborative process ensures that the standards SAS follows meet the customers’ expectations and requirements.

Communication is vital when making validated parts. Not only does SAS have regular contact with customers during the validation process for updates and progress, but they are also sure to immediately halt production and call the customer whenever SAS finds something that is not up to specifications.

Due to the cost and time overheads associated with validation, many manufacturers do not offer validated injection mold services, especially not on low volume orders. But, with the way SAS is setup, they are able to apply their skills and time to validate injection molding no matter the size of the order.

The Steps of Validated Injection Molding

Validation is a multi-step, detailed process. While there may be unique customer requirements, there are some steps that occur whenever a client requests validation.

Installation Qualification: Making Sure Everything Works

One of the ways validated injection molding differs from traditional processes is that it involves using IQ, or Installation Qualification. During IQ, the injection mold press equipment that will be used to manufacture a part is verified that it is installed correctly, working properly, and that the machine is receiving the proper power. This involves inspections from the manufacturer to make sure the equipment is set up correctly. The machines must be capable of repeatability and accuracy to meet all specifications.

Operational Qualification: Test, Test, and Test Again

After the IQ demonstrates that the equipment is correctly installed per manufacturer’s requirements, the next step of validation is to make sure the equipment is capable of performing over a specified range. This range is based on the material processing range and the processing parameters of the tooling and parts. This is called the Operational Qualification, or OQ phase. Here, data becomes especially important. An operator performs test runs, in which the operator records the machine’s operating settings by adjusting all manner of controls, including speed, pressure, temperature and more. Testers log, compile and store all data. This helps ensure the machines can operate over the processing range and notifies the operator if it falls out of the certain tolerances within that range.

Performance Qualification: The Real Thing This Time

Once OQ is complete, operators or technicians use the real manufacturing materials, while running the equipment through full cycles of parts. Basically, operators run the planned process for the part and verify that the process fits within the OQ range and the molded part meets all customer requirements. This is known as PQ, or Performance Qualification. During PQ, operators:

  • Record process parameters.
  • Ensure measurement accuracy for dimensional requirements.
  • Verify that materials behave as expected regarding durability and strength under various conditions.
  • Get customer approval that parts meet their specifications.

If PQ fails, it is back to OQ.

Lessons Learned

Formulating the validation process was a learning experience for SAS. Going through the validation process helped SAS to better plan out processes based on customer requirements and communicate the needs and importance to all levels of the organization. SAS now finds that it has less scrap when making any order, validated or not. Communication improved among all levels of employees. Learning that changing and updating processes is a good thing was something that became apparent to everyone. The importance of collecting and analyzing data, verifying processes and materials, and making sure everyone is clear on all steps became even more focused than it already had been.

Do you have an injection molding project that requires validation? Submit your design for review and a quote.

8 Questions to think about when choosing your Injection Mold Tooling

Posted on: September 13th, 2016 by Owen Timlin

Injection Molding is one of the most common ways to manufacture your product in production. The first step is choosing a tooling option that works for your project. Here are 8 questions from actual customers that will help make it a little easier to choose your Injection Mold Tooling.

Injection Mold Tooling

What is the scope of the project?

This is the probably the most important factor in determining which tooling method to use.

If the part is for pre-production then the answer is simple, aluminum tooling. This is common when the project requires the part to be made with the end production injection mold material. Aluminum tooling offers lower costs and faster lead times. If the material requirement is not needed see alternative options on RTV Molding and 3D Printing.

If the part is for production then there are a couple things to consider. What are the EAUs on the part? How long will the project run?

How does part size effect tooling?

Part size plays a big factor in determining tooling. Larger parts will need to be built in a standalone tool however smaller parts that fit within the size parameters may be subject to a (more efficient) cheaper alternative. Insert tools are extremely popular for smaller components. Instead of paying the full price of a standalone tool we can look to build an insert tool that fits into the (standard MUD) base unit on our press.

For example, you have a small housing that is 3″x 2″x 1/2″ and needs to be produced via Injection Molding. Instead of building a full standalone tool for such a small part we will build an insert tool out of aluminum or steel that fits into our pre-existing bases on our press. This is an extremely economical and waste minimization method to produce smaller components. We offer insert sizes ranging from a 5″x 5″ all the way up to a 11″x 14″.

How does part volumes effect tooling?

Part volumes can effect tooling especially when the volumes reach a higher level. The standard is a single cavity tool for low volumes of a couple hundred or a couple thousand parts per year, but as the part volumes grow you can look to add multiple cavities on the tool to produce parts more economically. When quantities and life of project are unknown or there is no solid forecast, single cavity tools are a good place to start. You can always look at building multi-cavity tools later on. Multiple cavity tools come with a little more upfront cost on the tool but it can significantly lower the piece price on your part.

Does part material effect tooling?

Yes, it does. The part material has direct effect on tooling for a couple of reasons. Mild injection mold resins like a Polypropylene are a lot easier on a mold therefore contributing to a longer tool life. Harsher injection mold resins like a Glass Filled Nylon wear down a tool much easier. This can be a crucial deciding factor when your part has a life of 8,000-12,000 pieces and you are deciding between aluminum or steel tooling.

Does part geometry effect tooling?

Yes, it does. We thoroughly evaluate each part before quoting. We look at part features that will effect the tool. Does it have undercuts? Cores? We also look at surface finish requirements. Will it be grained? Polished? Textured? These all effect the decision on the type of tooling used.

What is the life expectancy of a tool?

Aluminum tools are good for a lifespan of anywhere from 2,000- 10,000 parts depending on the type of aluminum used, part material and geometry.

Steel tools are good for a lifespan of 100,000 + parts depending on the material and geometry of the part. The tool may need re-worked after it has been in production for awhile.

What is the timeline to build a tool?

This changes on a part by part basis but a good rule of thumb would be:

Aluminum tools can be built in anywhere from 4-6 weeks for small parts and 6-10 weeks for larger parts while steel tools can be built in anywhere from 6-8 weeks for small parts and 8-12 weeks for larger parts.

What is the cost difference for Injection Mold Tooling?

This also changes on a part by part basis but typically a steel tool costs anywhere from 20-30% more then an aluminum tool.

TTH Injection Molding Glossary