A Guide to PE (Polyethylene) CNC Machining

Key Takeaways

• PE offers excellent chemical resistance, impact strength, and wear resistance for durable industrial and food-grade applications.

• Its low moisture absorption, self-lubricating properties, and light weight make it well suited for sliding and impact-prone components.

• PE has limited heat resistance, expands with temperature changes, and requires careful machining to control burr formation.

Characteristics of PE

PE (polyethylene) is a crystalline thermoplastic known for its toughness and chemical resistance. It is classified by molecular weight into high-density polyethylene, low-density polyethylene, and ultra-high molecular weight polyethylene.

For machined parts, high-density and ultra-high molecular weight grades are the most commonly used.

PE has a smooth surface with better wear resistance and self-lubricating properties than fluoropolymers, and it also performs well under impact at low temperatures.

Key Points

• Excellent chemical resistance

• Electrical insulation

• Excellent impact resistance

• Excellent wear resistance

• Specific gravity below that of water

• Low moisture absorption

• Suitable for food production applications

Types of PE

• Low-density polyethylene

• High-density polyethylene

• Ultra-high molecular weight polyethylene

Material Selection Notes

PE has a high coefficient of thermal expansion, meaning it is prone to dimensional changes with temperature swings. This makes it a poor fit for applications with large or frequent temperature fluctuations. Heat resistance is also low, so PE should not be relied on for strength in high-temperature environments. During machining, fine burrs form easily and are difficult to remove. Parts with small holes or passageways for fluid or gas flow require extra attention, as burring can compromise dimensional accuracy.

• Prone to dimensional changes with temperature fluctuations

• Low heat resistance

• Prone to burring during machining

PE CNC Machining at Yumoto Electric

Yumoto Electric manufactures custom PE machined parts starting from a single piece. We have experience with over 200 materials, including metals such as aluminum alloys, stainless steel, molybdenum, and titanium; and engineering plastics including PEEK, POM, and MC Nylon.

If you’re unsure about material selection or machining methods, we offer complimentary consultations to help optimize your design and production. For any questions, please feel free to contact us.