Investment Casting for Data Centre Cooling Systems: Engineering Reliability at Scale

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AI workloads and high-density compute are forcing a structural shift in data centre thermal management. Air cooling is no longer sufficient in many deployments, and liquid cooling is increasingly being designed into the infrastructure from chip-level cold plates to rack manifolds and facility loop integration.

In this environment, cooling systems are not “supporting equipment.” They are uptime-critical fluid networks that operate continuously under pressure, with tight control requirements and a low tolerance for leakage, contamination, or dimensional drift. Coolant Distribution Units (CDUs), piping assemblies, and rack manifolds are central building blocks of these networks, moving coolant between facility-side cooling and IT equipment-side cooling loops.

This is exactly where precision investment casting becomes strategically relevant: producing complex, leak-sensitive components that must be reliable, repeatable, and manufacturable at scale, often in corrosion-resistant alloys, while minimizing assembly complexity and failure points.

Where Investment Cast Components Sit Inside Data Centre Cooling Systems

Modern liquid cooling in data centres typically includes:

1) Coolant Distribution Units (CDUs)

CDUs circulate coolant, regulate temperature and flow, and interface between the facility loop and the technology (rack/server) cooling loop. They integrate pumps, heat exchangers, valves, sensors, filters, expansion tanks, and controls.

Typical castable component opportunities:

• Pump housings and impeller-related hardware (application-dependent)
• Valve bodies, filter housings, and end caps
• Structural flow blocks and manifold bodies (depending on design)
• Mounting brackets and corrosion-resistant hardware where geometry is non-trivial

2) Row / Rack Manifolds and Distribution Assemblies

Row-based manifolds distribute coolant from CDUs to server racks and are part of the secondary fluid network that bridges CDU output to in-server cold plates.

Castable component opportunities:

• Manifold bodies with internal channels
• Connector blocks/junction blocks
• Flow splitters/combiners
• Custom housings that consolidate ports and minimize welded joints

3) Direct-to-Chip and Immersion Cooling Infrastructure

Immersion and other liquid-cooling approaches introduce additional system-level requirements for material compatibility and long-term stability. Material compatibility is a recognized engineering concern in immersion cooling systems.

Castable component opportunities:

• Dielectric-compatible housings (design-dependent)
• Valve bodies and connectors in corrosion-resistant grades
• Structural components where internal geometry drives flow or packaging constraints

What Data Centre Cooling Demands from Metal Components

Data centre cooling hardware lives in a very different reality than “general industrial piping.”

Leak risk is existential

Liquid cooling’s performance benefits come with design and deployment challenges; leak prevention is a core risk-management requirement.

This pushes component design toward:

• Fewer joints and interfaces
• More integrated flow paths
• Stable sealing surfaces and port geometry

Flow stability matters as much as strength

In liquid loops, variability in port location, surface finish, and internal transitions can create uneven flow distribution, pressure drops, and localized hotspots—especially when systems scale across many racks.

Corrosion and chemical compatibility are always in scope

Cooling loops may use deionized water, glycol mixtures, and (in immersion systems) dielectric fluids. Different coolants and operating conditions raise compatibility and corrosion considerations that influence alloy selection and finishing.

Scale changes the economics of variability

At small volume, problems can be managed manually. At scale—across rows, zones, and multiple sites—repeatability becomes the performance requirement.

Why Precision Investment Casting Fits These Requirements

Precision investment casting is well-suited for applications where geometry, surface integrity, and repeatability directly affect system reliability.

1. Complex internal geometry without assembly complexity

Manifold and distribution blocks often require multiple ports, intersecting channels, and packaging constraints. Producing these via multi-piece fabrication increases welds, sealing points, and inspection load.

Investment casting enables near-net geometries that can reduce part count and simplify sealing strategy, then precision machining finishes the critical interfaces.

2. Surface finish and sealing performance

Investment casting is commonly used for valve and pump components, partly because it enables strong surface characteristics and geometry control prior to final machining. Shilpan Steelcast itself highlights typical as-cast surface finish ranges (Ra 3.2–6.3 μm) as relevant for flow-facing components.

In cooling systems, smoother flow paths and stable sealing faces can reduce risk at:

• O-ring grooves
• Flange faces
• Port interfaces
• Sensor and instrument ports

3. Alloy flexibility for corrosion resistance and durability

Data centre cooling hardware frequently uses corrosion-resistant metals for reliability under continuous operation (many commercial CDU solutions emphasize stainless steel pipework and durability-oriented designs).

Investment casting supports a broad set of ferrous/non-ferrous alloys (final selection depends on coolant chemistry, galvanic pairing, and operating regime), while machining delivers final tolerance control.

4) A predictable path to high-volume repeatability

The hidden cost in cooling infrastructure is rework and field failure. Casting + controlled machining + repeatable inspection plans create a disciplined route to consistent outputs—especially important for rollouts across many racks or multiple data halls.

Components Best-Suited for Casting in Data Centre Cooling

Below are high-fit categories where investment casting typically makes engineering and economic sense:

Manifold bodies and distribution blocks

• Multi-port geometry
• Tight packaging
• Internal channeling and junctions

Valve bodies and flow-control housings

• Pressure-containing components
• Sealing integrity
• Dimensional repeatability

Pump housings and structural flow components (application-dependent)

• Load + vibration
• Geometry integration
• Reliability requirements

Custom interface hardware

• Brackets, mounts, adapter bodies
• Consolidating parts to reduce joints

The governing principle is not “cast because it can be cast.” It is: cast when casting reduces interfaces, failure points, and variability—then machine the critical datums.

Engineering Considerations That Determine Success

To keep this practical for OEM engineering teams and integrators, these are the questions that typically decide whether casting is the right manufacturing route.

1) Where are the critical datums?

For cooling components, critical datums are often:

• Port-to-port center distances
• Sealing faces
• O-ring grooves
• Sensor thread locations
• Mounting patterns

Casting must be designed so machining can reliably reference and finish these without introducing stack-up errors.

2) What is the leak-test strategy?

Leak testing is often a downstream gate. High-performing programs design inspection and test requirements into the process plan early—especially for pressure-containing bodies and manifold assemblies.

3) What is the alloy/coolant compatibility model?

For deionized water, glycol, and dielectric fluids, compatibility drives:

• Alloy selection
• Surface treatments
• Cleanliness requirements

Immersion cooling literature, for example, explicitly treats material compatibility as a design consideration.

4) How will the program scale?

Scaling introduces:

• More installations
• More joints
• More variance exposure

Designs that consolidate functions into fewer robust components generally reduce operational risk.

How Integrated Manufacturing Improves Cooling-System Reliability

The manufacturing model matters because these components are not “just castings.” They are interfaces in an uptime-critical network.

A mature execution approach typically combines:

• Investment casting for near-net geometry and structural integrity
• Precision machining for sealing faces, threads, and datum control
• Assembly support for sub-assemblies (where applicable)
• Inspection and testing plans that detect deviations early

This integrated flow reduces handoff risk and preserves functional requirements from casting through final machining—especially important when manifold assemblies and valve bodies must meet system-level tolerances across many units.

Conclusion

Data centre cooling is becoming a high-reliability engineering domain. As liquid cooling adoption increases, so does the need for components that reduce leakage risk, stabilize flow, and remain consistent at scale.

Precision investment casting plays a practical role in this shift—particularly for manifold bodies, valve housings, and structural flow components where geometry integration and repeatability reduce system fragility. When combined with precision machining and disciplined inspection, casting becomes more than a manufacturing choice; it becomes part of the reliability design.

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