Glossary · Pneumatics and hydraulics
Fitting (fluid power)
Also known as: Tube fitting, Connector
German: Verschraubung
In fluid power, a fitting is a connector that joins tubes, hoses and components in a leak-tight way, for example a push-in fitting in pneumatics or a compression (cutting-ring) fitting in hydraulics.
- Fluid power
In one sentence
A fitting joins tubes, hoses and components leak-tight, such as push-in fittings in pneumatics or cutting-ring fittings in hydraulics.
Example
The hydraulic power unit uses 24° cone cutting-ring fittings, assembled with the torque and turns specified by the manufacturer.
How it applies
- Engineering: Fittings are selected by pressure rating, tube size, thread type and media. Mixing thread standards (for example BSP and NPT) causes leaks and failures.
- Commissioning: Hydraulic fittings must be assembled exactly as the manufacturer specifies; incorrect assembly can lead to sudden failure under pressure.
- Maintenance: Loose or leaking fittings are a common source of leakage and fluid injection injuries.
- Documentation: Specify assembly steps, torques and inspection checks, and warn never to tighten or loosen fittings under pressure. List thread types and sizes in the parts list.
Fitting vs. coupling
A fitting is a permanent or semi-permanent connection. A quick coupling is designed to be connected and disconnected frequently, often with self-sealing valves.