Key Differences in Components, Materials, and Precision Between Stamping Molds and Plastic Molds

When purchasing components for stamping molds and plastic molds, there are several critical differences in terms of component types, material requirements, and precision standards. Understanding these differences is essential for choosing the right parts for your mold manufacturing needs.

Stamping Molds vs. Plastic Molds: Component Types

Stamping Molds:

• Working Parts: The core components of stamping molds include punches and dies, which directly deform or separate the material. In industries like automotive, large punches and dies are used with high precision to shape metal sheets.
• Positioning Parts: These include components such as stopper pins and alignment pins, which control the material feed position. In electronic stamping molds, alignment pins are critical for accurate material positioning in each stamping cycle.
• Ejection and Pushing Parts: Components like ejector plates and push-out blocks are used to remove the stamped parts from the mold once the process is complete.
• Guide Parts: Guide pillars and guide sleeves ensure the accurate alignment of the upper and lower molds, improving both the stamping precision and the mold lifespan.

Plastic Molds:

• Molding Parts: In plastic injection molding, the core and cavity are the primary components determining the shape and size of plastic products. For example, molds for mobile phone cases require high surface finish and precision.
• Injection System Parts: Parts like main runners, branch runners, and gate sleeves direct the molten plastic from the injection nozzle into the mold cavity. Hot runner systems offer more complexity and require temperature control to maintain uniform plastic flow.
• Cooling System Parts: Cooling pipes and water channels regulate the mold’s temperature, ensuring the consistent quality of plastic molded products and improving the molding cycle time.
• Ejection Mechanism Parts: Ejector pins and ejector plates are used to push the molded plastic products out of the mold.

Material Requirements for Stamping and Plastic Molds

Stamping Molds:

• Working Parts: These components must endure impact, friction, and pressure. Common materials for high-hardness and wear-resistant components include Cr12MoV, SKD11, and other alloy steels. Stamping molds used for thin metal sheets require toughness, while those for thicker or high-strength materials demand higher strength and wear resistance.
• Guide Parts: Guide components, such as carburized steel or carbon tool steels (T8A, T10A), are used for their wear resistance and strength.

Plastic Molds:

• Molding Parts: These must withstand high temperatures, pressures, and the abrasive action of molten plastic. Materials such as P20 and 718 mold steels are preferred for their machinability, corrosion resistance, and thermal stability. For molds handling corrosive plastics, 4Cr13 or other corrosion-resistant steels are used.
• Injection System Parts: Materials are selected for their wear resistance and corrosion resistance, typically matching the requirements of the molding parts.
• Cooling System Parts: To ensure effective thermal conductivity, copper alloys and stainless steel are commonly used in plastic molds.

Precision Requirements for Stamping Molds and Plastic Molds

Stamping Molds:

• The precision of stamping molds is typically within ±0.05mm, though high-precision molds can achieve ±0.01mm. For industries like automotive, where stamping molds are used for large body parts, precision must be controlled to ±0.1mm. Smaller and more intricate stamped parts require even higher levels of precision.

Plastic Molds:

• Precision in plastic injection molding is also crucial. Typically, dimensional accuracy is controlled within ±0.03mm, with high-precision molds achieving ±0.01mm or even higher. For highly specialized products like optical lenses, sub-micron precision is required.

Procurement Channels and Supplier Selection for Stamping Molds and Plastic Molds

Stamping Molds:

• Procurement Channels: For stamping molds, you can source components from specialized mold accessory manufacturers or steel distributors for standard or custom parts. When selecting suppliers, prioritize processing capabilities, material quality, and cost-effectiveness. For large automotive stamping molds, long-term partnerships with reliable suppliers are crucial for ensuring consistent quality and stable supply.

Plastic Molds:

• Procurement Channels: For plastic molds, additional suppliers may be needed for specialized components such as hot runner systems. When choosing suppliers, it’s important to assess their technical expertise in plastic molding processes and their ability to provide support for complex molds, especially for industries like medical plastic molding that require high precision.