Gravity Casting

Gravity casting is a casting technique that uses gravity to naturally flow molten metal into a mold.

Unlike die casting, it does not rely on external pressure to force the metal; instead, the metal fills the mold solely under the influence of gravity.

Materials include

Aluminum alloys: Lightweight and corrosion-resistant, suitable for applications requiring weight reduction.
Copper alloys: Such as bronze and brass, known for good mechanical strength and wear resistance.
Steel and stainless steel: Ideal for parts requiring high strength and corrosion resistance.
Iron: Such as cast iron, which has excellent wear resistance and is commonly used in heavy-duty equipment.

Advantages:

Simple and low-cost process: Gravity casting does not require high-pressure equipment, and mold costs are relatively low.
Suitable for a variety of materials: Including many high-melting-point metals like steel and copper.
Integrity of castings: Since no external pressure is applied, the molten metal cools with less internal pores, resulting in a more uniform structure.
Suitable for casting complex structures: Parts with internal undercuts that cannot be formed by high-pressure die casting molds can be made using sand cores embedded in the gravity casting mold, making gravity casting more flexible for complex parts.

Disadvantages

Slower production speed: Gravity casting relies on natural flow, so the time to fill the mold is longer, making it less efficient compared to die casting.
Lower forming accuracy: Gravity casting typically results in lower precision and surface finish compared to die casting, often requiring post-processing.
Limitations for complex shapes: Due to the reliance on gravity flow, it is difficult to produce very complex shapes or fine structures.

Applications

Automotive industry: Used for manufacturing large engine blocks, brake systems, and other heavy components.
Piping and valves: Particularly suitable for casting large-sized pipe fittings, valves, and pump housings.
Mechanical industry: Used in the production of large castings for heavy equipment, agricultural machinery, etc.
Aerospace: Applied in the manufacturing of large structural components, especially those requiring high strength.