FAQ - Tubing and tubing connections

Tubes made from polyurethane (type PUN-.../ PUN-H-…/ PEN-...) are especially well suited to use in energy chains. For the minimum bending radius, the following rule of thumb applies: 10 x tubing outside diameter.

All compressed air tubing which is explicitly marked as such in the catalogue.

The Festo range includes a temperature and chemical-resistant hose made of perfluoroalkoxy (type designation PFAN). This hose is resistant to many acids and lyes, and can be used in a temperature range of -20°C to +150°C.

The products (fittings/tubing series) listed below can be considered resistant to the medium of water based on tests, provided the specified parameters are adhered to:

Fittings series:           CK, QS-F, QS *), CRQS, QS-V0

Tube series:                     PLN, PUN-H, PUN-V0, PAN-V0, PFAN

Adherence to the parameters (pressure and temperature) set out below is absolutely essential; at the same time, note that these parameters/usage conditions differ from the generally applicable pneumatic technical data for these components:

- Pressure range: 1 bar to 6 bar

-       Temperature range:        1°C to 50°C              

-       Medium:                        Normal tap water with no harmful additives

-       Pressure peaks must be within the specified pressure range.

*) G thread fittings from the QS series only with the use of OL sealing rings

The permitted leakage of 0.18l/h is a maximum value for push/pull fittings, which can occur under very unfavourable conditions. In contrast to use with air, a slight water leak can lead to consequential damage in case of a fault. As a result, Festo provides no guarantee of any kind, including for slight leaks. We strongly recommend that any installation undergoes a leak test before commissioning. To ensure that leaks are prevented as permanently as possible, even with fluctuating temperatures, the specified tightening torques must also be adhered to.

Fittings with parallel threads (G) are sealed off by a sealing ring between the screw fitting and the component. The connecting surfaces are usually flat machined for this purpose. Screw fittings with tapered threads (R) create a seal thanks to their slightly wedged shape, assisted by sealing tape or previously applied sealing material.

The pitch of a QSM-M7 fitting is 1mm (M7x1).

The part of the fitting that can be screwed into a valve (for example) may not exceed a maximum length. If you use Festo fittings, the length is guaranteed to be correct.