Spray wash vs immersion system - which one fits?
Spray and immersion systems clean series parts in fundamentally different ways. This guide compares both by throughput, part geometry and achievable cleanliness level, and shows when each system is the right choice.
View cleaning systemsHow do spraying and immersion differ?
In spray washing the cleaning medium hits the part surface under pressure (typically 1 to 3 bar). The mechanical impact of the jet removes loose chips, oils and emulsions. In an immersion bath the parts are fully submerged in the liquid, usually supported by ultrasound, circulation or basket movement.
The core difference is accessibility: a spray jet only cleans what it directly reaches. The immersion bath, by contrast, flushes every wetted surface evenly, including bores, blind holes and undercuts.
- Spraying: strong mechanical effect, short cycle times, low medium volume.
- Immersion: all-round wetting, ideal for complex geometry, often with ultrasound.
- Both methods run with aqueous cleaners or solvents.
Which system fits throughput and geometry?
The choice depends on three factors: required throughput, part geometry and target cleanliness level. For high volumes of simple parts a cycled spray system or a continuous conveyor is usually more economical, while complex parts with internal contours call for the immersion bath.
How to select the aqueous cleaner, pH value and concentration to match the material.
Read the guideHow is the required cleanliness level reached?
The cleanliness level is defined by particulate and filmic residual contamination, for example per VDA 19 / ISO 16232 for technical cleanliness. Spray systems remove particles effectively through jet force, immersion baths with ultrasound dissolve filmic residues and finest particles even from narrow gaps.
- Particulate cleanliness: spraying with sufficient pressure and nozzle distance.
- Filmic cleanliness (oils, greases): warm immersion bath with alkaline cleaner.
- Fine cleanliness: ultrasound in the immersion bath, then rinse stage and drying.
Frequently asked questions
When is spray washing more suitable than an immersion bath?
For high throughput of simple parts with well-accessible surfaces. The jet cleans quickly and uses little medium, but cannot reach deep internal contours.
Why does an immersion bath clean complex parts better?
Because the liquid flushes every wetted surface, including bores and blind holes. With ultrasound, filmic residues and finest particles are dissolved even from narrow gaps.
Can both methods be combined?
Yes. Many systems immerse first for all-round coarse cleaning, then rinse via spray nozzles to lift off cleaner and soil residues.
How do I measure the achieved cleanliness level?
Via technical cleanliness per VDA 19 / ISO 16232, meaning particulate residual contamination, complemented by filmic values such as residual oil content.
Looking for a spray or immersion system?
We help you choose by throughput, part geometry and target cleanliness level - from the compact immersion bath to the cycled spray system.
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Designed to VDA 19 / ISO 16232.
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