CNC Milling Machining Push Bar

CNC machining Push Bars, as injection mold parts, are mainly used for unloading and demolding, ensuring that molded products smoothly separate from the mold cavity.
Issues:
Product Marks: Visible scratches or indentations on products after ejection.
Burrs:Burrs at product edges during ejection.

Cause Analysis:
Product Marks: Insufficient hardness of the push bar material (e.g., ordinary tool steel) → Uneven ejection force distribution due to wear.

Burrs: Insufficient surface roughness (Ra > 0.8 μm) → High friction resistance, causing plastic melt adhesion.

Solutions:
Material Upgrade: Adopted SKH51 high-speed steel (Hardness: 62-64 HRC; wear resistance 3-5 times that of ordinary steel).
Surface Treatment: Polished to Ra ≤ 0.8 μm to minimize sticking.

Customer Feedback:
The product marks and burrs are completely solved, and the yield rate is increased to 99.5%.