In my last blog, we talked about what clamp tonnage is and how to calculate it of injection molding machine. Here, I’m going to write something about how clamp tonnage affects the injection molding process.
Selecting the correct tonnage is basically the foundation of starting your injection molding process. Excessive or insufficient tonnage – clamping force(pressure), can cause flash, damages and problems to the parts, mold and the machine.
Insufficient Clamp Tonnage = Short Moldings
Insufficient clamping force may lead to inconsistent weights, flash, wall section variation, poor surface finish, size variation, etc. If the clamp force is too low, it will be difficult to produce quality parts. Besides, machine and mold wear will be excessive.
Excessive Clamp Tonnage
When applying too much clamping pressure, there are molding defects that can be seen on parts almost immediately:
•Gloss level changes
Not only part quality can be affected when excessive clamp tonnage is applied, but also the mold and machine will be damaged due to excessive clamping.
Several of the long-term side effects on the mold:
• Crushed vents
• Rolled parting line
• Broken inserts
• Cracked core or cavity block
Potential failures on the molding machine when excessive clamping pressure is applied:
•Cracked hydraulic-cylinder mounting plates
•Fractured machine frame
From above we can see that too much or less clamp tonnage does no good to our injection molding purpose. It is very important to select an injection molding machine that provides proper clamp force, and avoid selecting one that provides excessive or insufficient clamp pressure for the job. A properly selected plastic injection molding machine will help make quality parts consistently and keep costs low and make you more competitive. Learn more about injection molding, welcome to visit our website: www.magneticplaten.com