Clamping force calculation is essential for injection molding projects to avoid expensive corrections later.
You can also read: Maximizing Injection Molding Simulation, Leveraging AI to Speed Product Design Simulations, Plastic Part Design for Economical Injection Molding – Part III
Tonnage means the maximum clamping force of an injection molding machine, ensuring tight mold closure during the injection process. At the same time, the clamping force acts as a steadfast guard, counteracting the specific pressure of the molten plastic and preserving the integrity of the product, avoiding defects like flash on the parting line of the part and/or tool damage.
Simulation results of clamping force under different process conditions to reach the desired machine capacity. The application is a thin wall packaging recipient.
To calculate the clamping force, the initial step is to calculate the projected area of the cavity, multiplied by the number of cavities, and subsequently add the sprue and manifold if this one is a cold runner. Subsequently, the second phase can unfold in one of two possible approaches:
For instance, the tonnage factor for a PP material ranges between 2 and 3 tons per square inch. If we have a thin wall recipient with a projected area of 140in² (900 cm²), the tonnage requirement would fall between 280 and 420 tons, taking the average of this value.
However, this calculation overlooks crucial factors such as the actual part geometry, gate design, and material properties (thermal and physical). This limitation restricts the accuracy of the calculation and prevents optimization opportunities for reducing clamping forces, potentially allowing for more parts to be produced in a smaller press.
We need to make sure that we are going to have enough clamping force to keep the mold closed during the injection process, even when there are viscosity changes in the material typical of the process. Nevertheless, for the injection molding machine, these types of potential failures occur when excessive tonnage exerts on the mold:
There is no good or bad way but it´s important to assess each project with the suitable tools and know-how to reach success and of course ROI.
To read more: How do I calculate the required tonnage for an injection mold?
As industries strive to integrate recycled materials into mainstream manufacturing, researchers continue to explore ways…
Companies worldwide are reevaluating their production processes. One major shift is the use of recycled…
On-site 3D printing of single-use consumables can help life science laboratories reduce carbon emissions.
As demand for sustainable, high-performance insulation materials increases, researchers continue to explore innovative ways to…
Polyurethane foams recycling rates remain low with less than 10% of polyurethane. Landfills receive millions…
Find ways to boost production, meet environmental regulations, and cut costs using data-driven tech solutions.