When it comes to injection molding, there are many ways to lower injection molding costs that can be monitored with a strategic plan and a good quality system. That starts with a good injection mold design, through the daily operations of the molding process, adding in secondary manufacturing, and logistical shipping to the customer. Today we’ll focus on the operational side of injectional molding, and list five ways you can reduce injection molding costs.
1. Choose a Resin with a Wide Molding Specification
When your product was first designed, a specific resin was chosen for its characteristics that could match the requirements of your product. Long-term durability, corrosion resistance, and more are often characteristics discussed before a resin is chosen. One option that is rarely discussed is how wide of a molding specification the resin has. You want to choose a resin that is flexible and easy to mold regardless of the environment changes that happen around the machine. Resin can change viscosity during molding, which can affect the quality of injection molded parts. Designing for changes, without causing extra rework or scrap parts, will help reduce daily operational costs.
2. Add Automation to Decrease Labor Costs
Automation and technology can lower variable operational costs over time. A human workforce can be very flexible, but they can add undue cost to a product. Consider adding a robot that can remove parts from an injection mold, remove the gate and sprue off every part, sort the parts, and possibly detect quality variations through visual management. Use trained personnel to make critical decisions when necessary and leave the repetitive easy work to automation. Repetition through automation will increase efficiency and decrease labor that can negatively impact cycle time.
3. Focus on Cycle Time Reduction
There are many steps to each injection mold cycle. Closing the molding halves, filling the mold, holding the mold closed for the part to cool, opening the mold, then removing the formed part(s). Smaller parts may only take seconds to complete the process, but larger parts may take minutes from beginning to end. Study the complete process and outline what factors contribute to each step of the process. Which can be changed to decrease time? Can you increase the resin temperature to make filling take less time? Can you reduce the holding time without causing a defective product? Perhaps you can change the resin composition slightly to decrease cycle time. There isn’t a perfect answer to what can reduce the time, but small amounts of changes can net large results. Just one second reduction over one-thousand cycles will net over 16 minutes of savings.
4. Increase Product Quality Training
One area that can always use more training is understanding product quality. Your customer expects a product free of defects. Does your staff know what that level of quality looks like, feels like, or functions like? If the answer is anything short of ‘absolutely yes’, then you can add training for your staff to increase their knowledge on good and bad product quality. Process variation will happen, and your operational goal is to stop the injection molding process when defective products are made. A knowledgeable staff will be able to detect the change in quality, and either adjust the molding parameters to return quality or notify someone who can.
5. Design Injection Molds to Reduce Transfer Times
Injection molds need to be removed from molding machines after they have produced the number of parts required. In their place, a new mold will be placed and different parts will be made. The goal with removing and replacing molds is to reduce the time it requires to complete the exchanges. Automatic clamps can be added, quick-disconnecting coolant lines can be added, and pneumatic tools can be used to quickly tighten down the holding clamps. As with molding cycle time, any reduction in time equates to more efficient operations and more uptime making profitable products.
These five tips are just the beginning when you’re seeking to lower injection molding costs of a product. Choosing a flexible resin, reducing cycle times, and adding automation can be lengthy discussions toward adding quality and reducing cost. When you need a resource to design your next injection mold, help select a resin with all the parameters needed for a successful product, or produce your product, we are here to help. SEA-LECT Plastics excels at injection mold design, tooling creation, manufacturing, assembly, and global logistics. We are a turnkey manufacturer that can organize a new product launch from concept to consumer. We have a complete turn-key option for your product. When you’re ready to discuss your current or next project, or want to know more about plastic injection molding, contact us at firstname.lastname@example.org or give us a call at (425) 339-0288.
Matthias Poischbeg was born and raised in Hamburg, Germany. Matt moved to Everett, Wash., after finishing his bachelor’s degree in business in 1995 to work for Sea-Dog Corporation, a manufacturer, and distributor of marine and rigging hardware established in 1923.
In 1999, Matt took over the reins at Sea-Lect Plastics Corporation, a sister company of Sea-Dog and a manufacturer of plastic injection molded products with an in-house tool & die shop. Matthias Poischbeg is also a contributor to Grit Daily.