Forging University: Open-Die Forging vs. Centrifugal Casting

Forging University: Lesson #5 – Open-Die Forging vs. Centrifugal Casting

Welcome back to Forging University! The fifth and last topic in our 5-part discussion compares two popular types of forging: open-die and centrifugal casting. Before reading on, take a quick look back to: Lesson #1, Lesson #2, Lesson #3, and Lesson #4 to review what we’ve learned. You can also check out Anderson Shumaker’s Forging page for more information.

What is Centrifugal Casting?

In January 2019, we discussed casting in manufacturing. Now, we’re looking at centrifugal casting (also called rotocasting). This method creates thin-walled cylinders. Centrifugal casting can use materials such as metal, glass, and concrete. Unlike other casting techniques, centrifugal casting manufactures rotationally symmetric stock materials. As a result, these materials are used in standard sizes for further machining.

What are the Advantages and Disadvantages?

Centrifugal casting can:

Produce long castings with the long axis parallel to the ground rather than standing up. Therefore, this evenly distributes the gravity.
Since it’s difficult to case thin-walled cylinders, centrifugal casting behaves in the manner of shallow flat castings relative to the direction of the centrifugal force
Manufacture discs and cylinder shapes where grain, flow, and balance are important to the durability and utility of the finished product
Also cast noncircular shapes, provided that the shape is relatively constant in radius

Open-die forging offers:

Excellent fatigue resistance and improved microstructure
Finer grain size and continuous grain flow
Increased strength (longer product life)
Reduced chance of voids in finished product
Less material waste (cost savings)

When open-die forging, machining is often required as a final step to achieve accuracy and desired finish. Luckily, Anderson Shumaker keeps machining and finishing in-house, saving our clients time and expense.