Die casting is an efficient manufacturing process used to mass-produce parts in a wide range of shapes, and these parts make their way into common items in our homes and workplaces. Die casting delivers a reliable process with a smooth, quality surface that won’t need any additional polishing or tooling.
The two most common methods of die casting are hot chamber and cold chamber. Learning the difference between these two options can help you evaluate and work with the right partner for your parts manufacturing. Let’s take a look at each type of die casting and learn about their benefits and drawbacks.
Cold Chamber Die Casting Basics
Cold chamber die casting is a preferred manufacturing process for metals that have high melting points, and it’s used by most of the top parts manufacturers in the industry. Typically, this will include metal alloys of aluminum, brass and copper. Cold chamber machinery requires additional equipment — usually an outside furnace and a ladle to pour the metal into the machine — for die casting. However, this allows the process to use materials that may be stronger and have versatile industry applications.
Molten metal must be ladled into the chamber directly, either through a ladle system or manually. Once the molten metal is loaded to a sufficient volume, it
will be injected into the die through a high-pressure hydraulic plunger. Pressure requirements for cold chamber castings are typically higher than those of hot chamber die castings.
Cold chamber die casting can also take as short as seconds for the die to solidify, though other simple designs take just a few minutes. Cold chambers are typically built to contain multiple cavities, so different machine parts can be created at the same time — either duplicates or a variety of different parts in the same mold.
Understanding Hot Chamber Die Casting
Hot chamber machinery contains the alloy melting pot as part of the machine itself and uses a gooseneck to inject material from the pot into the die. Internals of the machine pair the plunger and port to control how much molten metal is injected into the die.
When the port seals, the metal rests in the cavity to cool and solidify. Next, the plunger retracts and the casting itself can be removed once the die opens. This design allows hot chamber die casting to be a continuous process.
Because the melting pot is internal, hot chamber machinery is used for materials with lower melting points. The alloys are also limited to materials that won’t erode or dissolve the metal of the machine when put under heat or high pressure. Typical materials used in hot chamber die casting are zinc, lead and magnesium alloys.
Making Your Partner Choice
Selecting your partner for die casting and parts production comes down to your needs for cold chamber die casting and hot chamber die casting.
Start off by discussing your parts and the materials you want to use. We’ve discussed what metals and materials are available in each process, but your partner should be able to reiterate that during your conversation. Next, discuss the quantity that you’ll need and your timeframe, because that may give you access to lower costs or can restrict partners based on their overall capacity.
You’ll also want to consider certifications and standards that your partners will meet and use. We recommend starting by looking for partners who are ISO 9001:2008 companies because they’re proven to have a strong commitment to customer care and product quality.
Contact Premier Engineered Products if you have any questions about which process is best for your operations or how to address special considerations for your job.