A one-way flow control changes actuator speed in one direction while permitting freer flow in the other. Installing a supply-air version where the circuit expects exhaust throttling, adjusting the wrong port or opening both controls aggressively can produce stick-slip, impact and unstable timing.
Cylinder speed must be evaluated with the real load, pressure, cushioning and machine sequence. Depressurize stored air and mechanically secure the mechanism before inspection. The installed valve and cylinder manuals control adjustment direction and limits.
Decision matrix
| Control factor | Evidence | Decision |
|---|---|---|
| Valve function | Meter-in/meter-out symbol, flow arrow and port | Know which movement each control affects |
| Load | Horizontal/vertical, direction, mass and external forces | Identify runaway or gravity risk |
| Air condition | Supply pressure, restriction, leaks and exhaust path | Separate flow setting from system loss |
| End motion | Cushioning, stop position, impact and bounce | Protect the cylinder and tooling |
| Sequence | Sensor timing and repeated extend/retract time | Approve machine integration |
Map motion to valve function
Label cylinder ports, solenoid ports, one-way flow controls and sensors. Jog under the safe setup mode and record which control affects extend and retract. Read the printed symbol and flow direction; knob color or physical location alone is not reliable across manufacturers.
Festo explains that cylinder speed can be controlled in supply or exhaust direction depending on valve version. Confirm the intended circuit from the schematic. Do not reverse a check valve to force an adjustment range.
Stabilize pressure and mechanical load
Check regulated pressure during motion, not only at idle. Inspect tube kinks, silencers, valve exhaust, leaks and shared demand. A clogged silencer or undersized fitting can slow one direction even when the flow control is fully open.
Disconnecting the load casually can hide binding or create uncontrolled movement. Inspect guides, hinges, tooling and stops under isolation. For vertical loads, verify mechanical support and the approved method for preventing drop or runaway.
Start from a controlled slow condition
Record existing turns or scale positions before changes. Follow the component procedure to begin with restricted movement, then open the relevant control in small documented increments between cycles. Keep hands and instruments outside the motion zone.
Do not adjust both directions simultaneously. Observe whether the actuator moves smoothly through the stroke and reaches sensors without hammering the stop. If speed changes abruptly, investigate stiction, load or valve selection rather than continuing to open the control.
Coordinate speed with cushioning
End-position cushioning absorbs remaining kinetic energy; it is not a substitute for uncontrolled speed. Adjust speed and cushioning in the sequence specified by the cylinder maker, watching for impact, rebound, incomplete stroke and delayed sensor state.
A mechanism can arrive quickly but settle late, causing the PLC to see unstable timing. Measure from valve command to sensor transition over repeated cycles and record both travel and settling behavior.
Validate both directions in production sequence
Test extend and retract through startup, stop/restart and representative material load. Confirm pressure remains stable when other pneumatic stations operate. Lock adjustment devices where provided and retain protective caps.
Record valve type, positions, pressure trend, cycle timings and final product evidence. Send HANNAI a circuit photo, cylinder/valve codes and slow-motion video when speed balance remains unstable. Never publish one turn-count as a universal setting.
Technical references
- Festo one-way flow control valve guide — general component guidance; the installed machine documentation remains controlling.
Related machine and guide
Review the HN-M100 automatic paper cup machine for machine context, then use the pneumatic cylinder inspection guide for the adjacent check. Browse all Buyer Guides when building a wider project checklist.
Frequently asked questions
Are meter-in and meter-out valves interchangeable?
No. Their controlled flow direction and behavior under load differ.
Why is a cylinder fast but the sequence still late?
Impact, bounce, slow sensor settling or downstream logic may delay confirmation.
Should both flow controls be opened together?
No. Identify and adjust one movement at a time with recorded changes.
Can cushioning correct excessive speed?
Cushioning manages end energy but does not replace correct speed control.
Review your machine configuration with HANNAI
Send the machine model, project reference, component labels, drawings, photos and a description of the required result. We will clarify which details must be confirmed before a quotation or technical recommendation.