What is the Difference between Pressure Die Casting and Gravity Die Casting

What is the difference between Gravity Die Casting and Pressure Die Casting, and when would you use each one? This article will go through the Difference between Pressure Die Casting and Gravity Die Casting.

DEFINITION

Pressure Die Casting

Pressure Die Casting involves the injection of liquid metal into a mold under the influence of other external forces (except for gravity). The broad definition of pressure casting includes pressure casting, vacuum casting, low-pressure casting, centrifugal Casting, and so on. In contrast, pressure die Casting is a specific form of metal pressure. The most utilized and lowest-cost nonferrous metal casting processes are these.

High-pressure die casting is one of the two most common ways to deposit metal. High-pressure casting and low-pressure casting are distinguished. The technique of high-pressure die casting involves pouring molten alloy into a pressure chamber at high speed to fill the cavity of a steel mold. It solidifies the molten alloy under pressure.

Table 1 shows the different features of High Pressure Die Casting and Low-Pressure Die Casting

HIGH PRESSURE	LOW PRESSURE
The product has a high density, high strength, and surface hardness under the high-pressure molding, as well as a low elongation.	It isn’t limited by the technician’s experience.
Increased costs for mold.	Get the ideal casting. It’s simple to create directional solidification with few internal flaws.
Can’t be heat treated. The internal gas would expand during the process, causing a product bulge or fracture.	Materials are utilized in a wide range of applications.
High production efficiency and rapid prototyping are among its advantages.	Casting is used. There are no risers or runners, so the material cost and processing time can be reduced.
Too much machine work, may harm the surface dense layer and internal pore openings. This results in reduced product strength.	Automation is simple to implement and may be utilized in a variety of equipment and procedures.
The finish of the product is excellent.	They may be used in place of stone or concrete.
It’s capable of producing thin-walled components.	The surface is less involved. The pressure speed can be adjusted, and the molten soup is fed by laminar flow.

Gravity Die Casting

Gravity die casting is the term for putting molten metal into a mold under gravitational force of the earth, known as sand casting. Metal casting , investment casting , clay casting, are all examples of gravity die casting.

The pouring of liquid aluminum into the gate by hand is typical in gravity casting. It fills the mold cavity, exhausts, cools. It also opens the mold to get the sample depending on the self-weight of the liquid metal. The flow of a gravity casting operation is as follows: molten aluminum smelting, material filling, exhaustion, cooling, opening the mold, clean up production operations.

PRESSURE DIE CASTING VS. GRAVITY DIE CASTING: ADVANTAGES AND DISADVANTAGES

The quality of casting produced by each method varies. Pressure Die Casting can make accurate and complex castings that are correct. It have thinner walls thanks to the quick filling of the mold under pressure. As-cast surfaces are often very smooth, which reduces secondary machining.

While Gravity Die Casting can’t match these features, the lower rate at which molten metal enters the mold. This results in less folding and turmoil, resulting in less trapped air in the casting. Because the molten metal is gravity fed into the mold, Gravity Die Casting has a slight edge over Pressure Die Casting strength after heat treatment.

Table 2 shows the advantage and disadvantages of Pressure Die Casting

ADVANTAGE	DISADVANTAGE
Many pressure die castings can be plated without further treatment if desired.	More difficult to mass-produce or individual cast, which get more expensive as the number of them decreases.
Ability to mass-produce identical metal components at a high degree of accuracy.	It’s difficult to work with, and it uses pricey equipment
The castings with thin walls are lighter in weight.	When compared to gravity die casting, they are rather inflexible.
A cost-effective solution for large castings.	For the installation, you’ll need a significant sum of money.
The surface finish should be smooth, without pits or other imperfections, with no paint overspray on the surface.
For faster manufacturing, molten metal solidifies in a matter of seconds, or even milliseconds.
Suitable for long production runs or high quantities.
Before being replaced, each component may be produced by the machine thousands or even millions of times.
Ideal for intricate, precise components
Ideal for a wide range of uses.

Table 2 shows the advantage and disadvantages of Gravity Die Casting

ADVANTAGE	DISADVANTAGE
Materials are usually used.	The procedure is simple but not suitable for thin-walled components.
The method is simple and can be used for large-scale manufacturing.	The low production efficiency adds to the manufacturing cost.
Because there are so few pores in aluminum casting, it may be heat treated.	The product has a low surface finish and is simple to create divots after shot blasting.
The component may be made from aluminum alloys with low fluidity.
The cost of the mold is modest, and it offers a long service life.

THE DIFFERENCES: A SUMMARY

Gravity casting is the process of filling liquid aluminum into a mold using gravity, as opposed to forcing it in. Centrifugal casting, is another method that belongs to the realm of gravity casting. The principle of die casting is to pour liquid aluminum into the injection chamber using mechanical force, such as an injection rod.

The Pressure is created as the injection rod and injection head move linearly, forcing liquid aluminum to fill the mold.

Gravity casting is often used for parts with complex internal shapes (such as gasoline refueling guns), whereas die casting is typically utilized for parts with complex external forms but simple internal structures (such as the gearbox, etc.).

CASTING TYPE	High Pressure	Low Pressure	Gravity
PROCESS	Complex	Simple	Simple
MOLD COST	High	Low	Low
MOLD LIFE	Short	Long	Long
POROSITY	Worse	Good	Good
HEAT TREATMENT	No	Yes	Yes
MACHINING ALLOWANCE	Small	Big	Big
SURFACE FINISH	Good	Good	Worse
APPLICATION	Thin Wall	Average	Thick Wall
EFFICIENCY	High	Average	Low

JC Casting is an industrial casting business. We specialize in assisting our customers to save money through more efficient supply solutions. We both specialize in Pressure Die Casting and Gravity Die Casting. Whatever you need, we got it for you. We take pleasure in our capacity to address difficulties and make your life simpler. Contact us today, and tell us how we can help you and your company!