The Hidden Cost of Casting Porosity
In the naval and maritime industries, the integrity of a component is a critical safety requirement. Yet, many engineers still struggle with the inherent risks of castings: subsurface porosity, gas pockets, and structural voids that remain hidden until they cause a failure.
Many shipbuilders may have relied on casting vs. forgings due to costs and time savings, only to be faced with these quality hurdles. Often, after a lot of headaches and frustrations, the solution becomes clear: converting castings to forgings.
Forging vs. Casting: A Performance Comparison
| Feature | Castings | Forgings |
| Internal Structure | Random grain; prone to voids/porosity. | Refined, directional grain flow. |
| Structural Density | Risk of leaks under pressure. | 100% dense; no internal voids. |
| Strength | Lower impact and fatigue resistance. | Superior strength-to-weight ratio. |
| Machinability | High scrap rate due to hidden defects. | Consistent and predictable machining. |
Eliminating the “Porosity Trap” in Naval Applications
Castings are created by pouring molten metal into a mold. As the metal cools, gases can become trapped, leading to porosity. In high and low-pressure naval environments, these microscopic holes can lead to catastrophic leaks.
Press and hammer forges use mechanical pressure to refine the grain structure. This process physically closes internal voids. For shipbuilders, this means zero porosity and no more rejected parts during final inspection.
Superior Strength through Directional Grain Flow
When you forge a part, the metal’s natural grain flow is redirected by the forging die to follow the contour of the component. This creates directional strength, making forgings significantly more resistant to impact and fatigue than brittle castings. For mission-critical flow control, this durability is non-negotiable.
Reducing Lead Times and Scrap Rates
Nothing kills a project’s timeline like machining a cast component for ten hours only to uncover a massive void in the final pass. Because forgings are free of inclusions, you experience:
- Predictable Machining: Consistent density protects your tooling.
- Lower Scrap Costs: Eliminate the financial hit of poor material integrity.
- Urgent Turnarounds: Our in-house die design gets your conversion projects moving immediately.
Traceability and Compliance (MIL-SPEC & NQA)
Shipbuilders operate under the world’s strictest codes. At US Drop Forge, we inventory original mill test reported materials with UNS category grades. Our ISO 9001:2015 and PED certifications ensure that every forged part has a digital paper trail, something many casting foundries struggle to provide.
How to Convert Your Casting to a Forging
Transitioning doesn’t have to be a technical headache. Our engineering team can work with your existing casting specs to develop a modernized tool and die program. We specialize in custom jobs and small runs, and pride ourselves on fast turnaround times, ensuring your builds stay on schedule.
