【126】The steel philosophy behind 1 million mold cycles

【126】The steel philosophy behind 1 million mold cycles

With a mold lifespan of 1 million cycles, what does this number signify? It means continuous production around the clock for two shifts a day, and this mold can be used for two and a half years; it means that during these two and a half years, the customer doesn't have to worry about the mold for this product, doesn't need to keep inventory, and doesn't have to worry about sudden supply disruptions; it means that the value created by this mold is dozens or even hundreds of times its own price.

But to reach this figure, the first hurdle that needs to be overcome is the selection of steel materials.

There is a common misconception within the industry: the more expensive the mold steel is, the better. But that's not true. The right one is the best. Just like cooking, not all dishes require using veal, and not all molds need to be made of the highest-grade steel. The key point is: what material should this product be made of? How many molds should be produced? What are the requirements for surface smoothness? Is there any corrosiveness? Is there a risk of wear and tear?

We have a veteran mold maker who has been working for 17 years and is specifically responsible for steel type selection. His mind is like a living steel manual, knowing exactly the performance corresponding to each steel grade, the heat treatment process, and the price range. Once a client requested to produce fiberglass-reinforced nylon, which is notorious for damaging molds, the mold would be worn down like sandpaper by the fiberglass. The conventional solution was to choose hard alloy, but it was costly and difficult to process. The veteran proposed an alternative: key parts would be embedded with powder high-speed steel, while non-key parts would use ordinary mold steel. The hardness would be achieved at HRC58-60 through heat treatment, and a diamond-like coating would be applied. This solution only costs half of the full hard alloy, yet the lifespan can reach over 90%.

The customer accepted it with a mixture of doubt and curiosity. Now that mold has been used for over 800,000 cycles, and the wear on the critical parts is less than 0.02 millimeters. It is expected to easily exceed one million cycles. The customer's production director said, "You're not selling molds; you're teaching us a lesson."

Selecting the right type of steel is only the first step. The heat treatment process is equally crucial. For the same type of steel, different quenching temperatures, different numbers of tempering processes, and different cooling methods result in vastly different performance. We collaborate with a heat treatment factory that has a history of over forty years. Their experienced workers can adjust the heat treatment parameters based on the shape, wall thickness, and purpose of the mold. For some large molds, to prevent deformation, they need to undergo three repeated tempering processes, each lasting for about ten hours. This process is time-consuming and energy-intensive, but it ensures the dimensional stability and internal stress release of the mold.

The most extreme example is a multi-chamber mold designed for a medical enterprise, which requires the use of medical-grade PEEK material. The molding temperature of this material is as high as 400 degrees Celsius, and the working temperature of the mold also needs to be heated to around 200 degrees Celsius. Under such working conditions, conventional steel molds will become soft through tempering after continuous production for several thousand mold cycles. We chose heat-resistant mold steel, developed a special heat treatment process, and applied a PVD coating on the mold cavity surface. This mold has now been used for over 600,000 mold cycles and is still in good condition.

The customer asked a question: How much higher is the cost of your approach compared to the ordinary molds? After calculation, it's approximately 25% to 30% higher. But the customer's calculation is like this: An ordinary mold might break down after 300,000 mold cycles and require a one-week downtime to replace it with a new mold, resulting in a loss of several million in production value. Our molds can produce 700,000 more mold cycles, and the additional production value is enough to purchase ten new molds. This 25% premium actually buys us peace of mind and stability for the next two and a half years.

Therefore, 1 million mold cycles is not our goal; rather, it is our commitment to our customers: Once this mold is delivered to you, you only need to focus on production and don't need to worry about the mold. The rest of the matters have all been taken care of for you by us during the design, material selection, and heat treatment processes.

The lifespan of a mold determines the "quality of sleep" of your production line. Golden Eagle molds ensure you can rest peacefully for two and a half years.