This article is sponsored by The Rodon Group, a high-volume, custom plastic injection molder.
The mold setup procedure is an unavoidable part of injection molding. During this process, the molding machine is shut down for a period of time while the mold is changed. Sometimes, however, setups are mismanaged and, as a result, machines sit idle for far longer than they have to.
What’s more, an inferior setup can lead to sluggish cycles, high scrap rates, tool damage, flawed parts, rework, an unsteady process, and delayed product delivery. Shops could even erase their entire profit margin on the job as a result of a flubbed mold change procedure.
So how do you avoid all these potential fiascos?
According to an article published in Plastics Technology, the answer lies in focusing on refining the mold setup procedure, instead of doing it perfunctorily.
Injection Mold Setup Checklist
Ready to take the next steps?
Use this checklist to help you steer clear of common mold setup mistakes while also perfecting the injection molding setup procedure.
Step 1: Reduce idling during the pre-stages of the injection mold change procedure.
Instead of waiting for the molding machine to finish its current run, let the changeover crew perform some of its duties while the press is still in production. Specifically, the crew should be setting up the next mold while the press is still working on the previous mold.
A mold change cart is especially handy for this purpose. It should hold all of the tools that the team is going to need for removing the previous mold and setting up the new one, including torque wrenches, impact wrenches, mold clamps and bolts, nozzles, cleaners, etc. A crew member should have a mental injection molding machine startup checklist memorized to help ensure all the necessary tools are in the cart.
The crew should also schedule and stage injection molding materials before the molding machine completes its last cycle. Neglecting to do this could cause a press to stay inactive for a much longer period than all the steps in the mold change procedure combined. For example, many materials need to be pre-dried for two to six hours before processing. Prepping materials alone can help cut changeover time dramatically.
Step 2: Fast track the injection molding machine startup procedure by clearly labeling and organizing mold inventory.
Molders can avoid wasting time on locating and retrieving molds by organizing storage. First, they should store and inventory molds so that they are easy to find. Second, they should make sure that they position the storage close to the press for quick and easy retrieval.
Injection molding manufacturers should utilize a mold storage rack that stands adjacent to the press. On the rack’s shelves, clearly numbered molds should be assigned specific spots on specific racks. Organize the molds strategically; for example, place the most frequently used molds in the most accessible areas.
Create a standard injection molding setup procedure.
Without an established process for changing molds, manufacturers may prolong the setup process as well as introduce other inefficiencies into their operations. In order to eliminate the possibility of missteps, it can be helpful to create a set of guidelines that detail the proper tools and techniques for the injection molding setup procedure.
These guidelines can help production supervisors ensure that each scheduled mold setup is performed on time. In addition, they can allow personnel to evaluate and analyze every changeover and pinpoint areas for improvement.
Step 3: Train more people to handle the mold setup procedure.
Mold setups can also take longer simply because not enough people in the shop know how to conduct a mold changeover. Even small molding shops sometimes have several machines simultaneously requiring a changeover, yet many molders continue to have only one or two changeover specialists.
To prevent situations in which presses are staying idle because specialists are too busy to get to them, shops should train press operators to perform mold changeovers. By increasing the number of employees who can handle this process, it allows mold setup procedures to be performed more regularly and with greater speed, as press operators will be able to assist in all steps of the process.
In some cases, creating teams of two operators can be particularly effective, regardless of the size of the press. With a two-person team, each team member can have predetermined duties and work on each side of the molding machine.
Step 4: Consistent communication is crucial, especially with injection mold setup procedures.
Production schedules can be unpredictable and can leave molders rushing to figure out last-minute details right before the press has to be set up. To avoid a stressful or chaotic situation, molders should hold production meetings every day.
Cross-functional teams can convene daily to review the schedule, talk about concerns, and evaluate priorities and resources. These constant discussions help to pre-empt and reduce unexpected problems throughout the operation, including mold setup procedures. Moreover, these meetings allow for the exchange of ideas, which paves the way for process improvements.
Step 5: Maintain equipment to prevent injection molding machine downtime.
Some molders make the mistake of neglecting equipment maintenance, an oversight which can lead to a wide range of equipment problems, including busted ejector pins, damaged bolt holes on platens, or threadbare check rings. All of these issues, in particular, could protract the mold setup procedure and ultimately depreciate your bottom line.
Lessons Learned
It’s time to take the checklist to the shop floor and put these tips to good use. By sticking to this injection mold setup checklist, companies will be more able to execute many changeovers for both larger and smaller presses.
