+86 17727725162 jqj014950@topstarltd.com

Home / How to solve platen damage problems: High-rigidity platen design for electric injection molding machine

How to solve platen damage problems: High-rigidity platen design for electric injection molding machine

2025/11/10 By le zhan

How to solve platen damage problems(1)

Damage to the clamping platen in an electric injection molding machine can lead to unplanned downtime, parts scrap, and additional emergency repair costs. As an injection molding machine manufacturer, we recognize that the root cause lies in insufficient platen design strength, which cannot withstand the high precision and high-strength forces required by electric injection molding machines. Therefore, we employ high-rigidity clamping plates in our electric injection molding machines, built through comprehensive stress analysis and optimized design strength, fundamentally solving this problem.

Impact of Clamping Platen Damage in Electric Injection Molding Machine

The clamping platen is a core component of any injection molding machine, holding the mold in place during mold closing and injection. For electric injection molding machines, due to their faster mold closing speed, higher precision, and more stable pressure, the impact of clamping platen damage is more severe. If the clamping platen sustains damage, it will cause additional downtime, and technicians may take 3 to 21 days to repair or replace the damaged clamping platen. Furthermore, a warped or misaligned clamping platen can lead to uneven clamping pressure, resulting in flash, short shots, or dimensional errors. Most critically, a cracked clamping platen can cause catastrophic failure under clamping pressure, endangering operator safety and damaging expensive molds.

Clamping platen damage is not just a maintenance issue; it threatens your profits and poses production safety risks. For electric injection molding machines that rely on precision for performance, clamping platen damage negates all those advantages.

The Root Causes of Clamping Platen Damage in Electric Injection Molding Machine

The forces generated by electric injection molding machines differ from those of other injection molding machines, making them more prone to clamping platen damage. Understanding these reasons will show you why a high-rigidity design is necessary:

High Clamping Force Density: Electric injection molding machines use smaller, more compact actuators to provide clamping force, resulting in higher stress concentration on the clamping platen.

Rapid Clamping Speed: The electric servo motor accelerates the clamping platen, generating impact forces that a fragile platen cannot absorb.

Precision Requirements: Electric injection molding machines are typically used to process parts with tight tolerances, so even a 0.1 mm warpage of the clamping platen can lead to quality problems.

Thermal fatigue: The heating and cooling cycles of the mold cause repeated expansion and contraction of the platen, creating microcracks that can widen over time—especially on thin, poorly designed platens.

Mold misalignment: Even slight mold misalignment can cause uneven stress on the platen, leading to mold deformation or cracking.

A Topstar engineer noted, “We found that platen damage is most common on electric machines operating at high speeds 24/7. These machines were originally designed for hydraulic systems, not the precise, high-impact loads of electric systems.”

The Root Causes of Clamping Platen Damage in Electric Injection Molding Machines

High-rigidity platens based on stress analysis

To address the platen damage issue, Topstar first conducted a comprehensive stress analysis, a crucial first step in designing a high-rigidity platen capable of withstanding the unique forces of an electric injection molding machine. Next, we used finite element analysis (FEA) software to simulate all the forces the platen would experience: clamping pressure, injection back pressure, rapid clamping impact, and thermal expansion. This allowed us to identify stress hotspots that standard platen designs could not detect. Following this, we conducted actual load testing, fabricating a prototype platen and running it at maximum load on an electric injection molding machine for 1000 hours to simulate five years of production. This validated the results of the finite element analysis and revealed potential weak points.

Then, we perform mold compatibility analysis, analyzing how molds of different sizes and weights cause uneven stress distribution on the pressure plate. For example, eccentric mounting of large molds can lead to uneven stress distribution; our finite element analysis takes this into account, thus reinforcing critical areas.

High-rigidity plate design strength optimization

Stress analysis reveals where engineers should reinforce the structure, but optimizing the design strength ensures the plate remains rigid enough without becoming too heavy or reducing motor performance. Topstar’s high-rigidity pressure plate employs three key design features:

Strengthened Rib Structure: We use internal ribs to reinforce stress concentration areas. These ribs are arranged in a grid pattern, matching the motor’s force path, increasing rigidity by 40% without adding extra weight.

Precise Thickening: Instead of overall thickening, we only thicken high-stress areas such as mold mounting holes and actuator connection points. This maintains the lightweight design of the pressure plate while increasing its strength.

Reinforced Mounting Points: Mold clamping holes and actuator mounts are areas of highest stress. We added steel inserts and rounded edges at these points, reducing stress concentration by 65% ​​compared to standard platens.

For electric injection molding machines, achieving a balance between rigidity and weight is crucial. A packaging mold manufacturer who has worked with us stated, “Our previous platens were very heavy, causing our injection molding machine cycle time to increase by 0.5 seconds. Topstar’s high-rigidity platens are lighter yet more rigid, resulting in shorter cycle times, and we haven’t experienced any warping issues.”

High-rigidity platens based on stress analysis 2

Materials and Manufacturing of Durable High-Rigidity Platens

Topstar uses S45C carbon steel for the high-rigidity platens because it combines strength, rigidity, and machinability. Compared to standard low-carbon steel, this alloy offers better resistance to thermal fatigue and microcracks.

Engineers precision-machine the entire pressure platen using a five-axis CNC milling machine, ensuring that the flatness error of the entire surface stays within 0.02 mm. Even minute unevenness can lead to uneven clamping pressure, which is crucial for the precision of electric injection molding machines. After machining the clamping plate, engineers perform heat treatment to eliminate internal stresses generated during manufacturing, preventing the plate from warping once it is put into use. These measures ensure that the clamping plate maintains its rigidity and flatness even after more than 10 years of high-intensity use.

electric injection molding machine 10-10

Solving Clamping Plate Damage with High-Rigidity Clamping Plates

Topstar’s high-rigidity clamping plates, based on comprehensive stress analysis, optimized design strength, superior materials, and precision manufacturing processes, completely eliminate cracks, warping, and misalignment. It protects your investment, reduces downtime and scrap, and ensures your electric injection molding machine performs at the speed, precision, and efficiency you expected when you purchased it. As an injection molding machine manufacturer, we are committed to providing solutions to the practical problems faced by injection molding users, enabling you to achieve more efficient production.

 

Prev: Injection Molding of Flexible Materials: Precautions for TPU/TPE Processes

Next: Mastering the 160℃ mold temperature controller: Which materials require 160℃?

TRENDING POSTS

HOT TOPIC

Get A Quick Quote