Cold-chamber die casting — basic machine principle In a cold-chamber die casting machine, a measured ladleful of molten metal is transferred from the separate melting pot into the shot chamber and then forced into the closed die cavity by hydraulic pressure on the plunger. Is this description accurate?

Introduction / Context:
Die casting machines are categorized as hot-chamber and cold-chamber. The choice depends largely on alloy reactivity and melting temperature. Understanding the metal feed path is foundational for process planning, cycle time estimation, and die thermal management.

Given Data / Assumptions:

• Machine type: cold-chamber die casting.
• Molten metal is held in a separate furnace or holding pot.
• Metal is ladled into the shot sleeve before plunger injection.

Concept / Approach:
In cold-chamber machines (used for aluminium, magnesium, and brass), the injection system is not immersed in the melt. A fixed or mobile ladle transfers a metered quantity into a cool shot sleeve, after which a hydraulic plunger injects it into the die at high pressure. This setup avoids corrosion of the injection mechanism and permits higher melt temperatures than hot-chamber systems.

Step-by-Step Solution:

Verification / Alternative check:
Process schematics for cold-chamber machines universally show ladling into a horizontal shot sleeve followed by plunger injection and intensification.

Why Other Options Are Wrong:

• “Incorrect” or alloy-limited options: hot-chamber differs; aluminium alloys use cold-chamber specifically.
• “Metal is always melted in the shot chamber”: this describes hot-chamber, not cold-chamber.
• Vacuum assist is optional; description remains correct without it.

Common Pitfalls:
Assuming hot-chamber operation for all die casting; overlooking that the cold shot sleeve temperature affects fill and porosity.

Final Answer: