Integrated Thermal Flow-Channel Cleaning Line

The integrated thermal flow-channel cleaning line was delivered in 2024 to a leading domestic thermal management Tier 1 supplier (shown as an industry-generic description under customer confidentiality constraints). It brings precision cleaning, drying and cooling into a single one-piece-flow line, so cold plates, manifolds, heat exchangers and coolant lines are cleaned and finished without being transferred between separate machines.

The line strings cleaning, drying and cooling — 3 stages — into one sequence, with an operating flow of tray loading, directional flushing, multi-stage filtered media recirculation, vacuum drying, and cooling with unloading. Keeping every stage on the same line removes the transfer steps that would otherwise re-contaminate a cleaned part, and the takt is 30–180 s per piece depending on the workpiece.

Cleaning uses an aqueous precision cleaning chamber in which the media is recirculated through multi-stage filtration, so loosened particles are carried out of the circuit instead of settling back onto the part. Drying follows with multi-stage high-efficiency and vacuum drying, cooling uses air or nitrogen, and automated tray transfer moves parts between stages without manual handling.

Cleanliness is controlled at micron-level particle residue. After cleaning, extracted media can be assessed to ISO 16232 / VDA 19.1 for particle size distribution and residual contaminant mass, with a residual-particle reference of ≤ 200 μm and flushing pressure up to 0.8 MPa; the exact limits follow the customer's cleanliness specification. Process parameters are logged automatically for batch traceability and the line can connect to MES, and the modular architecture lets the same configuration be replicated on comparable product lines while keeping the 30–180 s takt window.

Residual particles inside thermal-management flow channels are a hidden risk in new-energy thermal products: particles in micro-channels contaminate the coolant circuit, clog passages and reduce heat-exchange efficiency, and any that break loose can wear pumps and valves. Such contamination usually surfaces only at assembly or during system operation, so the cost of rework and field failure far exceeds the cleaning step itself — which is why cleanliness has to be held to a measurable particle criterion rather than judged visually clean.

Compared with the traditional arrangement of a separate cleaner, dryer and cooling bench, the value of the integrated one-piece flow is that all three stages run on one line: a part is never transferred between machines, so the particle re-attachment and water marks that handling causes disappear, along with the work-in-process waiting and floor space between machines. Cleaning, drying and cooling are linked within a single takt window, and the part leaves the line ready for downstream assembly.

Drying is split into multi-stage high-efficiency drying followed by vacuum drying because flow channels with blind holes and tight corners trap moisture that hot air alone cannot reliably clear; the vacuum stage pulls the remaining moisture out before the part cools. Cooling then uses air or nitrogen — nitrogen where the surface must stay free of oxidation — and automatic tray transfer moves each part between stages so the cleanliness achieved in the chamber is not compromised afterward.

The line is delivered as a turnkey system covering the aqueous precision cleaning chamber, multi-stage high-efficiency and vacuum drying, air or nitrogen cooling, automatic tray transfer and process-parameter traceability, and it has been validated in production. The delivered line suits cold plates, manifolds, heat exchangers and coolant lines, and can be extended to oil coolers, flow plates and end caps, supplied either as a full line or matched to the customer's existing layout. Cleanliness acceptance limits follow the customer's cleanliness specification, and process parameters are logged per batch to support the data-traceability requirements of an IATF 16949 audit. Because the three stages share one control system, the process window is defined once and repeated for every part, so the same cleanliness result holds across a full production run rather than being re-established per machine.