A pneumatic system involves more than the tubing itself. Tubing carries compressed air, one-touch fittings connect tubing to pneumatic components or equipment ports, and valves and other airflow-control components provide functions such as shut-off, one-way flow, and manual on/off control.

Accordingly, the configuration process can be considered in the sequence “Tubing Selection → Fitting Connection → Airflow Control.” Tubing is selected based on how it will be used and the operating conditions, while the fitting connection is confirmed based on the tube O.D., equipment port thread, and fitting type. Where shut-off, one-way flow, or manual on/off control is required, the corresponding airflow-control component can be considered.

What Do Tubing, One-Touch Fittings, and Valves Do?

Tubing, one-touch fittings, and valves all serve different functions within a pneumatic system.

Within a pneumatic system, these components respectively handle fluid transfer, connection, and airflow control.

Step 1: Tubing Selection

Pneumatic tubing should be selected based on the application, whether it will be subject to frequent movement or repeated flexing, and the operating environment, rather than on material type alone.

For example, tubing that moves with equipment or undergoes repeated flexing is used differently from tubing that remains largely stationary after installation or moves only slightly. Tubing used with air tools or for on-site air supply may also be dragged, moved, extended, or retracted during use.

For more information on tubing selection for different routing methods and operating conditions, refer to “How to Select Pneumatic Tubing: A Guide to Routing Methods and Operating Conditions.”

Step 2: Fitting Connection

Once the tubing has been selected, the next step is to confirm how it will be connected to a pneumatic component or equipment port using a fitting.

Tube O.D.

When using one-touch fittings, make sure the tube connection size matches the actual tube O.D.

Equipment Port Thread

For fittings with a threaded end, the thread type and size of the port on the equipment or pneumatic component also need to be confirmed. Examples include metric M, PT, NPT, and G threads.

Fitting Type

Fitting types can be selected based on the connection direction, branching requirements, and available installation space. Common types include straight, elbow, tee, and Y-type fittings.

Step 3: Airflow Control

Once the tubing and fitting connection details have been confirmed, a corresponding airflow-control component can be selected if shut-off, one-way flow, or manual on/off control is also required.

Stop Fitting: Shuts Off Airflow After Tube Removal

For tubing sections that require disconnection, air flows normally with the tube inserted. When the tube is removed, the stop fitting shuts off airflow at the fitting to help reduce continuous compressed-air loss.

Check Valve: Allows One-Way Flow

A check valve can be considered when airflow needs to pass in one direction while reverse flow is prevented. When selecting and installing the valve, the indicated flow direction should match the intended airflow direction.

Hand Valve: Provides Manual On/Off Control

A hand valve can be considered when an operator needs to manually turn the compressed-air supply on or off for equipment or a specific section of the pneumatic system.

For more information on the classification and selection of SHPI one-touch fittings and related airflow-control product series, refer to “One-Touch Fittings Overview | Classification and Selection Criteria.”