Secondary Fluid Network & Cooling Header Sizing

Secondary fluid network headers are sized based on total cooling demand, required coolant flow rate, allowable fluid velocity, and system pressure-drop limits.

Engineers begin by calculating the expected cooling load across the connected racks and determining the coolant flow needed to remove that heat.

Titan Fittings recommends evaluating header length, pipe diameter, coolant properties, future capacity requirements, and losses through valves and fittings before finalizing header dimensions.

A 4-inch cooling header is commonly used for data center rows with moderate aggregate coolant flow requirements.

Larger 6-inch or 8-inch headers may be appropriate for higher-density installations, longer distribution runs, or systems requiring additional future cooling capacity.

There is no universal flow threshold for each size. Actual selection depends on internal diameter, flow rate, coolant properties, velocity limits, and pressure-drop calculations.

Titan Fittings supplies stainless steel reducers and transition fittings that support connections across 4-inch, 6-inch, and 8-inch cooling header configurations.

Higher rack power density generally increases the amount of heat that must be removed by the liquid cooling system.

For a given coolant temperature rise, increased heat load requires additional coolant flow. As total flow rises, larger headers may be needed to maintain acceptable fluid velocities and pressure losses.

Titan Fittings recommends sizing headers for expected rack density and considering future expansion before installing the secondary fluid network.

Data center cooling headers are often designed for moderate coolant velocities, commonly in the range of a few to several feet per second.

The appropriate design velocity depends on pipe material, coolant chemistry, temperature, noise limits, erosion concerns, and allowable pressure drop.

Titan Fittings recommends selecting header diameter based on the project's hydraulic calculations and applicable engineering requirements rather than applying one fixed velocity target to every system.

Pressure drop represents the resistance coolant encounters while moving through the distribution system.

Undersized headers, long piping runs, restrictive fittings, valves, and quick disconnects can increase pressure losses and pumping requirements.

Titan Fittings recommends evaluating the pressure drop across the complete secondary fluid network, including rack-drop connections, when selecting headers and distribution components.

Appropriately sized headers and low-restriction fittings can help improve overall pumping efficiency.

Rack-drop connections typically require branch fittings, stainless steel reducers, adapters, isolation ball valves, flexible hose assemblies, and quick disconnect couplings.

These components transition from larger secondary fluid network headers to smaller rack-level supply and return lines.

Titan Fittings supplies 304 and 316L stainless steel fittings and connection components for 4-inch, 6-inch, and 8-inch header configurations, including reducers, full-port isolation valves, flexible hose connections, and OCP LQC quick disconnects.