How are internal channels cast and validated in heat exchangers?

How Are Internal Channels Cast and Validated in Heat Exchangers?

Precision Casting of Internal Channels in Heat Exchangers

Internal channels in die-cast heat exchangers are critical for controlling fluid flow, thermal distribution, and system efficiency. At Neway Die Casting, internal channel geometry is formed using high-precision tooling and optimized gating systems. Alloys like C12200, A380 aluminum, or Zamak 3 are selected based on thermal requirements and casting fluidity.

Methods for Creating Internal Channels

Core Insert Technology

Steel or ceramic core pins are used to form straight or branching internal passages. These are either ejected post-casting or designed as sacrificial inserts for complex geometries.

• Suitable for high-volume, repeatable internal geometries

• Tolerances typically held within ±0.1 mm in flow passages

• Used in multi-path manifolds and pressure vessels

Soluble or Sand Cores

Applied in aluminum and copper casting when channels have complex shapes or blind branches.

• Washed out or broken down after solidification

• Enables intricate multi-directional cooling or refrigerant paths

Vacuum Die Casting

Minimizes porosity and incomplete fill issues within long or thin internal paths, especially critical for pressure-based heat exchanger functions.

Validation and Quality Inspection of Internal Channels

Neway validates internal channel integrity through the following methods:

Pressure Leak Testing

• Components are sealed and subjected to hydrostatic or pneumatic pressure (up to 5 MPa)

• Detects pinholes, shrinkage cavities, or incomplete fill

• Complies with ISO 14903 and UL 207 testing standards

X-Ray and CT Scanning

• Non-destructive imaging of internal features

• Identifies voids, cold shuts, or misaligned cores

• Routinely applied for batch validation and new tooling approval

Airflow and Flow Rate Testing

• Confirms unobstructed passage of fluids or gases

• Used for calibrating multi-port channel dimensions

Application-Specific Channel Designs

Customer-Oriented Casting Solutions for Heat Transfer Components

Neway provides full-service support for heat exchanger manufacturing, including:

1. Aluminum and Copper Die Casting: Forming complex internal channel structures with tight control over wall thickness and geometry

2. Tool and Die Creation: Customized tooling for internal core insert layouts

3. Non-Destructive Testing: X-ray and leak detection to verify casting integrity