RP Coating Ejector Punches for Heavy Load with Dowel Holes

This heavy-load ejector punch variant is used in injection mold tooling where sustained punching force and thermal stress can quickly degrade conventional coated punches. It is suited for automotive connector and bracket molds that run high cycle counts, because the Al-Cr based RP coating with alpha treatment is intended to maintain wear resistance and coating adhesion during repeated heating and cooling.

In appliance and electrical housing cavities, the center-style heavy-load configuration with dowel holes helps maintain guided alignment under load. That alignment reduces side loading on the tip, supporting stable ejection timing and improved component durability.

For consumer goods molds with deep-core ejection, the available shank diameter range (10–45 mm) and multiple tip geometries (round, rectangle, oblong, and variations) allow engineers to match the ejector contact profile to the part geometry, helping reduce localized wear at the punch tip.

RP coating ejector punches use an Al-Cr based RP coating designed for high hardness and heat resistance in severe punching environments. The included alpha treatment is used to improve adhesion of the coating film to the punch substrate, addressing a common failure mode where coatings delaminate after thermal cycling.

While the provided specifications focus on coating and dimensional variants, the intended performance balance is clear: the Al-Cr RP coating is selected to enhance wear resistance under elevated temperatures, while maintaining adequate toughness for repeated ejection cycles. In practice, this coating approach trades pure substrate toughness for a stable hard, thermally resistant surface that lasts longer on the moving punch face.

• Coating system: Al-Cr based RP coating
• Surface conditioning: alpha treatment for stronger coating/substrate bond
• Heat resistance focus: improved stability during repetitive mold heating and ejection

Select an ejector punch geometry by matching the shank and tip dimensions to the mold’s core/cavity structure and the part ejection contact area. Start with D (shank diameter) in the range of 10–45 mm, then verify the available L (length dimension) options: 60–130, 70–130, 60–100, or 70–100 mm, depending on the required stroke and bolster/plate stack-up.

Next, choose the tip profile and size for the ejection interface. Available tip shapes include round, rectangle, oblong, double flatted round, and radius rectangle, with tip dimension parameters P (5–35 mm), W (5–9 mm), and a corner radius R (0.15 mm) where applicable. The LC (full length alteration) range (e.g., 47–129.9 mm up to 54–129.9 mm, with shorter variants down to 53–99.9 or 54–99.9) must align with the mold’s required clearance and machining allowances.

• Guided alignment: confirm dowel-hole alignment features for reduced side loading.
• Tolerance/fit: keep standard drill/jig and dowel fits consistent with your mold assembly drawings to prevent binding during ejection.
• Configurable vs. fixed: D, tip shape, and length options are configurable within the listed ranges; R is fixed at 0.15 mm in the provided data.