Q&A Questions and Answers


service units
What is a service unit?

Service units are used in pneumatic systems to prepare the compressed air – the energy source. Here you can see a typical KNOCKS compressed air service unit for a very high air purity class, with a tap for lower quality (in accordance with the draft version of VDMA 15390-1:2013-11).

Why is compressed air preparation with a service unit so important?

If you want your pneumatic components and controls to function properly throughout their expected lifespan, correct preparation of the compressed air is vital. Dirt particles, water and chemical contaminants can all have a negative impact on both your compressed air consumers and the air network. Whereas solid specks can lead to mechanical wear, moisture is likely to cause corrosion. Rust particles, in turn, can result in mechanical destruction or block flow cross sections.

Air purity classes
acc. to DIN ISO 8573-1:2010

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