Core Pins
Tolerances: Depending on geometry and application, tolerances can reach 0.000050 inches (0.00127 mm) in roundness and size.
Description: CraftAlloy™ tungsten carbide core pins used to form internal features in plastic injection molded parts.
Key Functions
Core pins are rigid, precision components inserted into the mold cavity to create internal features in a molded part. During injection, molten plastic flows around the pin, forming holes or internal geometries as the material cools. Because plastics exert high pressure on the pin, stiffness is critical, and any bending leads to dimensional inaccuracies.
CraftAlloy™ tungsten carbide (developed by Crafts Technology and now part of Hyperion’s portfolio) delivers exceptional rigidity, ensuring minimal deflection and reduced core shift for highly accurate molded parts. Strategically harnessing CraftAlloy™ Tungsten Carbide on components within your injection molding process can minimize tool deflection and reduce molding cycle times by up to 40%.
Types
Hyperion develops custom core pins tailored to meet unique mold designs and challenging geometries.
CraftAlloy™ is a tungsten carbide grade engineered specifically for injection molding, optimized by Hyperion to deliver the ideal balance of hardness and toughness required for demanding molding conditions. Learn more about how CraftAlloy™ Carbide Core Pins improve core deflection.
Custom Core Pins
Custom core pins are engineered to meet unique mold designs, tight dimensional requirements, and challenging geometries. In addition to manufacturing high‑precision carbide solutions, Hyperion partners closely with customers throughout the project lifecycle to ensure optimal results.
Hyperion’s custom core pin support includes:
- Recommendations for transitioning existing steel pin designs to tungsten carbide, improving stiffness, tool life, and dimensional stability
- Engineering support for CAD drawings, including design reviews and material selection guidance
- Design and application troubleshooting to address deflection, wear, or molding performance challenges before and during production
Combined with Hyperion’s advanced carbide manufacturing capabilities, this collaborative approach enables customers to achieve:
- Extremely tight tolerances
- Maximum stiffness with minimal deflection
- High‑precision micro‑features
- Repeatable accuracy across long production runs
Material Properties
Hyperion manufactures high‑performance tungsten carbide core pins engineered for applications where core deflection is the primary limiting factor in part quality. CraftAlloy™ carbide delivers:
- Exceptional rigidity and stiffness, dramatically reducing core pin bending under high injection pressures
- Dimensional stability for long, slender geometries, where even minimal deflection can result in ovality, flash, or scrap
- Near‑zero wear, even when molding abrasive materials such as glass‑filled resins or PEEK
- High thermal conductivity, supporting faster heat removal and more consistent cycle times
- Extended tool life, significantly outperforming traditional steel or copper‑based alternatives
Core Pin, Insert, and Bushing Material Properties
|
Material Type |
Craftalloy™ CP Tungsten Carbide |
Craftalloy™ CPT Tungsten Carbide |
420SS |
H13 |
P20 |
M2 |
Copper‑Beryllium Alloy (98% Cu, 2% Be) |
|
Young’s Modulus of Elasticity (kpsi) |
85,000 |
77,600 |
30,000 |
31,000 |
30,000 |
30,000 |
19,000 |
|
Young’s Modulus of Elasticity (GPa) |
586 |
535 |
207 |
214 |
207 |
207 |
131 |
|
Thermal Conductivity (Btu/ft·hr·°F) |
60 |
60 |
14.4 |
14.2 |
17.3 |
11 |
75 |
|
Thermal Conductivity (W/cm·°C) |
104 |
104 |
24.9 |
24.5 |
30 |
19 |
130 |
|
Thermal Expansion Coefficient (×10⁻⁶ / °C) |
5.5 |
6.2 |
10.3 |
10.4 |
12.1 |
11 |
17.3 |
|
Thermal Expansion Coefficient (×10⁻⁶ / °F) |
3.06 |
3.44 |
5.7 |
5.8 |
6.7 |
6.1 |
9.6 |
|
Density (g/cm³) |
14.4 |
14.0 |
8.03 |
7.8 |
7.86 |
8.14 |
8.36 |
|
Density (lb/in³) |
0.52 |
0.50 |
0.29 |
0.28 |
0.284 |
0.294 |
0.302 |
|
Specific Heat (Btu/lb·°F) |
0.051 |
0.051 |
0.11 |
0.11 |
0.11 |
0.11 |
0.091 |
|
Specific Heat (J/kg·K) |
213 |
213 |
460 |
460 |
460 |
460 |
380 |
|
Hardness (HRc) |
~80 (92 HRa) |
~76 (90 HRa) |
52 |
54 |
48 |
66 |
42 |
|
Poisson Ratio |
0.22 |
0.23 |
0.24 |
0.30 |
0.29 |
0.29 |
0.30 |
|
Wear Resistance |
Best |
Best |
Good |
Good |
Good |
Good |
Poor |
|
Cost |
$$ |
$$ |
$ |
$ |
$ |
$ |
$ |
* All values are close approximations; actual values may vary.
Because of these characteristics, CraftAlloy™ core pins are best suited for high‑precision injection molding applications involving long, thin‑walled, or deep internal features, where steel pins are prone to bending or core shift.
Typical applications include molded components with long, unsupported internal holes, thin‑wall sections requiring tight positional accuracy, and micro‑features where even micron‑level deflection impacts part function.
In these applications, resistance to bending is the dominant performance driver. CraftAlloy™’s superior stiffness minimizes deflection during injection, helping manufacturers maintain tight tolerances, improve repeatability, and reduce scrap across long production runs.
