Compressed Air Distribution via Hoses or a Piping System?

We are often asked about solutions for compressed air distribution using hoses. It is sometimes assumed that hoses offer a cheap and practical way to set up a compressed air network in the workplace. In practice, this is not the case — a piping system is usually the more practical and cost-effective solution.

When to Choose Hoses?

When we speak of a point of use — the connection between the main piping network and the tool — it makes sense to use a hose. For workplace accessibility, you can choose a hose reel, a loose hose, or a spiral hose. You could say that a length of around 25 metres per user, with one user per hose, is practical.

Hoses Are Unsuitable for Distribution from Compressor to Workplace

If hoses are used for distributing air from the compressor to multiple workplaces, this is strongly discouraged and in many cases not even possible.

The reasons why hoses are impractical depend on several factors:

• As the hose diameter increases, the working pressure usually decreases — especially with PVC hoses. The specified pressure is often measured at 20 °C, whereas piping networks are often installed high in the building where it may be 10 °C warmer, further reducing the maximum allowable pressure.
  Example: DICFLEX25 (25x33) is rated at 10 bar at 20 °C.
• To connect hoses and make branches, fittings (hose barbs) must be used. These are inserted into the hose, meaning each connection creates a narrowing that restricts optimal flow.
  Example: plug-in nipple DRF.SP05-19/OR (3/4” male thread with Ø19 barb). Although the barb has a Ø19, the nipple bore is only Ø15 due to wall thickness.
• Hoses cannot be neatly mounted along walls. They require a lot of clamping and are difficult to install in a straight, professional way.
• Condensate is normally removed by installing piping with a slope. With hoses this is far more difficult, as hoses tend to sag, preventing proper drainage of condensate.
• Not all compressed air hoses are moisture-resistant, which is crucial considering condensate in the system. You would need to choose hoses specifically resistant to moisture.
  

Aluminium Piping Becomes More Cost-Effective as Diameters Increase

In practice, an aluminium piping system is often the better option. As the diameter increases, aluminium piping generally becomes cheaper compared to hoses.

Installing a Piping System Underground

Another frequently asked question is whether a compressed air network can be placed underground. In general, we strongly advise against embedding an air piping system in a floor (assuming it will no longer be accessible afterwards). Placing piping or hoses directly into concrete is highly unadvisable.

Reasons include:

• Condensate will always collect at the lowest point. The section in the floor will be the coldest point, where condensate will form — and since this section is inaccessible, it will be impossible to remove the moisture.
• Piping expands and contracts. It is unpredictable how a system will behave when it cannot expand or contract freely.
• Piping directly cast in concrete can be damaged by the concrete itself.
• Piping should always be placed in a protective sleeve, which adds costs and time.
• Leaks cannot be repaired.
• Segmenting the system with shut-off valves is impossible, as valves will be inaccessible.
• Future adjustments and extensions are no longer possible.