After wave, selective or reflow soldering, every PCB assembly carries flux residue that must be removed before conformal coating or final inspection. The two standard industrial solutions are inline conveyorized washers and offline batch cleaning machines. Both can reach IPC-compatible ionic cleanliness levels — the right choice depends on your volume, budget and production layout.
Throughput and Production Flow
An inline PCBA cleaning machine connects directly to your SMT line: boards travel through wash, rinse and drying zones on a conveyor without operator handling. Modern inline systems process a full pallet of boards in a cycle time of two to six minutes, making them the standard for plants running more than roughly 300 to 500 boards per day with multiple shift operation.
Offline batch machines clean a basket or pallet of boards per cycle, typically 20 to 60 minutes including drying. They fit lower-volume production, prototypes, repair and rework stations, and lines where the cleaner is shared between several soldering processes. One operator can serve several machines, and the equipment can be moved as the line layout evolves.
Cost Considerations
Investment differs significantly: offline batch washers cost a fraction of an inline system, and their consumable consumption (water-based cleaning fluid, DI water, filters) per batch is easy to measure. Inline systems justify their higher price through labor savings, consistent cycle times and full-line integration. Calculate cost per board rather than machine price: at high volumes the inline system usually wins; below a few hundred boards per day the batch machine is more economical.
Cleaning Consistency and Traceability
Inline machines hold spray pressure, fluid temperature and conveyor speed constant, which simplifies process validation for automotive or medical customers. Batch machines offer flexible recipe changes — useful when switching between no-clean, water-soluble and rosin flux types — but require disciplined operator execution.
Our Recommendation
As a rule of thumb: stable high-volume production with one dominant flux type favors an inline washer; mixed production, small batches and growing companies favor an offline machine first, with an inline system added as volume grows. We supply both types and can size the right machine from your board dimensions, daily volume and flux type — send us your requirements for a free process proposal.