Tag Archives: injection mold design

Design Plastic Injection Molds to Press Specifications

A plastic injection mold designer must consider many factors when designing injection molds, including the press the mold will run in.  Knowing the press specifications is very important in order for the mold to operate properly, and most efficiently during injection molding production.  

Vertical Press Clamping System

The orientation of the clamping system is of course a very important consideration, as this determines whether the mold will open horizontally or vertically.  A vertical molding press is used in over-molding production, also called insert molding because the molten plastic is molded around an object.  An example would be an electrical wiring harness with plastic molded around a portion of it, clamps or even something like knives where the handle is molded around the metal.  

The insert in a vertical molding press can be either steel or even plastic.  A vertical press requires molds for the top and bottom, as a vertical molding press has a rotary table which holds at least two bottom (B) sides of the mold, while the top half (A) half comes down to close on the bottom half molding the part.  

There is usually one top half, and at least two or more bottom sides to the mold, so that when the A side is molding the part on the back of the table, another B side is in front of an operator or a robot loading an insert into the open mold.  Once molded, a robot or operator can unload the over-molded part from the mold, prior to loading new inserts into it.   Constructing molds for a vertical molding press is quite different than for a horizontal molding press, even though the concept is the same.  

Horizontal Molding Press

The most common type of injection molding operation is in a horizontal press, requiring an A side and B side, closing together on a horizontal plane to mold the parts.  When the horizontal mold opens for ejection, parts usually fall into a bin below or are grabbed by a robot and taken to an inspection area.  Most horizontal molding operations do not require an operator at the press, as the vertical over-molding jobs do without automated equipment.   

Horizontal molding presses are very efficient and non-labor intensive, with a top-quality high-performing injection mold, a horizontal molding operation can run for hours in a lights out environment.  

Regardless of whether the mold is for a vertical or horizontal press, the placement of water fittings and hoses is of the utmost importance in designing the tool.  The clamping pressure and press tonnage are also very relevant specifications, in order for the mold designer to calculate the pressure of the molding operation while also considering the material chosen and how it will flow into critical areas.  

Michiana Global Mold has decades of experience designing tools for various plastic injection molding environments, meeting tight tolerances with high performing, precision custom injection molds.  Download a FREE copy of our book “Design Considerations for Different Molds” for more information.

Michiana Global Mold has decades of experience designing and building precision custom injection molds for various industries. Contact us today to speak with one of our knowledgeable engineers for a FREE design consultation on your mold building requirements.  We can custom design molds for your applications, regardless of your molding environment.

Mold Design Considerations for Thermoplastic Resins

The most common type of polymer used in injection molding is thermoplastic resins.  There are many different types of resins with various properties to meet part specifications for functionality.  When designing injection molds, the engineer must take into consideration all properties of the resin specified for the produce including adhesion, elasticity, resistance to high temperatures, shrink rate, resistance to corrosives, and desired finish whether matte or polished.

 

The cooling and shrink rate are of the utmost importance, as some parts with a high shrink rate will need the cavity designed accordingly so the finished product will cool and shrink within specifications.  Cooling rate is also important for ejection, as the resin must completely solidify prior to mold ejection.

When an injection molded part has a critical functionality, mold flow analysis may be helpful in determining resin flow into tight geometric areas.  Mold flow analysis clearly shows with computer aided simulation how the resin will flow as determined from its properties.  Predicting how thermoplastic resin will flow in the mold and cavities prior to cutting steel can be a valuable tool in avoiding costly mistakes.  Conducting the proper advanced quality planning with mold flow analysis can greatly improve lead times.  

Most journeyman mold makers will already possess the knowledge of hos particular resins flow just from experience.  A skilled design engineer with experience in manufacturing molds will have the knowledge to design the tool to produce a part to print specifications, with the chosen resin properties playing a huge role in tool design.

At Michiana Global Mold, we have been providing high quality precision molds for over 60 years, possessing more than 500 years of combined experience.  Our staff of highly skilled design engineers and journeymen mold makers are the best in the business with vast experience in various thermoplastic resins.

Contact Michiana Global Mold today to speak with one of our skilled and experienced mold designers to learn how we can assist you with your injection mold requirement.  We are an ISO9001:2015 Registered mold making company with vast experience constructing custom, precision injection molds for various industries.

Custom Plastic Injection Mold Making

 

A custom plastic injection mold maker has expertise with designing a plastic injection mold to manufacture a unique plastic part.  Custom injection mold making is used in several industries, especially those requiring new parts with new model releases such as the Automotive Industry.

 

When new projects require complex parts that fit into existing assemblies, or critical components used in interior automotive parts, you need a precision custom plastic injection mold making company.  At Michiana Global Mold, no part is too complex.  We excel at designing and manufacturing precision, tight tolerance, custom designed molds for critical components.  Our specialty is providing quality precision tools for complex, custom parts.  

 

Michiana Global Mold employs highly skilled designers and engineers, utilizing the latest technology to design the perfect tool for your complex part requirements.   Using Unigraphics software, we can create 2D and 3D models of the optimum design, quickly identifying critical dimensional areas prior to cutting steel.

 

Our designers and journeyman mold makers have vast experience designing complex tooling, even molds that require cam action or customized ejection systems.   Your custom injection mold will be designed to run in your press, and within your unique environment.   We’ll take your water lines and mounting plate into consideration for optimum placement, avoiding any future discrepancies with a smooth-running mold.

 

Full Service Injection Mold Making Supplier

 

Michiana Global Mold is a full-service injection mold making company, with over 600 years of combined experience.   Our knowledge, expertise with mold making, and vast resources give us the opportunity to provide the best value to our customers.  

 

We have a partnership with Modular Mold Solutions, located in China, giving us the ability to source tools overseas while still providing the same quality that you expect from a superior domestic mold making supplier.   

 

Both of our locations, in China and here in the US, are registered to ISO9001, following a strict quality policy in all processes.   We practice continual improvement on a regular basis, passing savings onto our customers with improved efficiencies and consistent quality.  

 

 

Michiana Global Mold is a full-service injection mold making company, providing high performance plastic and rubber molds to a multitude of industries including automotive, consumer products and electronics since 1964.  Contact us today to learn about our  free design consultation  and multi-tool discount for high volume projects.  

Ejection Systems and Lifters in Injection Molds

 

The ejection system is a very important part of an injection mold design.  The ejection system must correspond to the stroke of the press, and work in perfect harmony with any auxiliary equipment utilized in the press.  The ejector pins must also be placed where they will eject the part without causing any damage to the part.  This can be tricky with small intricate molded product, it may be difficult to find the right angle to eject an oddly shaped part with critical dimensions or thin walls.  In some cases, lifters must be used just for this purpose, to eject the parts properly and without causing damage.

If lifters are required this must be apparent prior to building the mold.  This is where an experienced mold designer will determine the best placement of any required lifters in the ejection system.  A lifter is part of the ejector plate, activated during ejection.  They are usually angled and slide up when required during ejection, allowing the part to mold all dimensional features properly.  

If auxiliary equipment is attached to the press such as sprue pickers, the ejector system, whether it includes lifters or not, must always accommodate any automated auxiliary equipment.  Sprue pickers are automatic robots that reach into the mold when it opens to grab the sprue, also called the runner, and move it out of the way usually dropping into a bin or grinder to grind up and re-use the material.  A two-stage ejection system is sometimes used with a robot grabbing the sprue, and the parts falling onto a conveyor or into a bin below.  

Utilizing the latest technology with CAD/CAM software, Michiana Global Mold can design your complicated precision injection mold with an ideal ejection system.  We have experience designing and building precision molds requiring complex ejection systems, utilizing lifters, and accommodating the injection molder’s press specifications.  

Contact Michiana Global Mold today for an expert mold design and injection mold construction with quality steel and components.  We have been an integral supplier of injection molds for over 50 years, employing skilled designers and journeyman mold makers.   Michiana Global Mold is registered to ISO9001:2015, adhering all processes to our strict quality policy.  Contact us today for a free design consultation of your next mold building project.

Designing and Building Complex Three-Plate Tools

 

 

Experienced mold designers must know how to adapt to challenging geometrical dimensional specifications.  Employing a three-plate tool can be a solution when searching for an ideal gate location, or when multiple gate locations are necessary.  

 

A three-plate tool has an additional stripper plate acting as a buffer between the injecting plate containing the multiple gate locations, and the B plate housing the cavities to mold the parts.  With this precision design, the sprue is ejected in between the first and second plates, and parts eject in between the second and third plates.  This allows for the parts and runner to separate, and is easily adapted with any automated auxiliary equipment just like any other mold and ejection system.

 

A Three-plate tool design can provide a more consistent flow to cavities with multiple gates, without the need for a hot-runner tool.  In most cases a three-plate tool will be less expensive than a true hot-runner tool, but still provide the increased pressure to fill and pack critical dimensional areas with an even flow of material.  This is beneficial in areas containing thin walls or tight tolerances.  

 

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Michiana Global Mold has vast experience designing and building complex three-plate tools for various industries, including the demanding quality standards of the Automotive industry.  We have experience building three-plate tools, hot-runner tools, hot-to-cold tools, MUD units, Prototype Tools, Shuttle Molds, and more.  

Our vast resources allow us to provide you with complete service from design to mold construction and even product sampling.  We follow a strict quality policy, adhering all processes to our ISO9001 registration.  Our experience and resources allow us to provide quick turn-around on single or multi-tool projects.  

Contact Michiana Global Mold today for a free design consultation, and to learn more about our innovative and technologically advanced mold building capabilities.  We have what it takes to be an integral part of your valuable supply chain, providing solutions to your mold building projects with quality built tools, delivered on time and to your specification.