Airtac PSL Throttle Speed Control Fitting PSL401AD-S
SUS304 stainless variant (-S)The AirTAC Airtac PSL Throttle Speed Control Fitting PSL401AD-S is a genuine speed controller, threaded elbow with knob with aluminium-alloy locking cap and fixed tube direction, used to set the speed of a pneumatic cylinder by throttling its air.
- TypeSpeed controller, threaded elbow
- SeriesPSL
- Working pressure0 - 1.0 MPa (0 - 10 kgf/cm2)
- Proof pressure1.5 MPa
- AdjustmentKnob with aluminium-alloy locking cap
- Temperature-20 to +70 °C
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac PSL Throttle Speed Control Fitting PSL401AD-S
The PSL401AD-S is a stainless-trim inline speed controller that throttles air in one direction and lets it pass freely in the other, so you set the stroke speed of a small actuator instead of letting it slam. The A suffix makes this the meter-out version: flow from the 1/8in thread port to the Dia 4 tube is controlled, while the return path runs free. AirTAC lists meter-out as the first-priority choice because throttling the exhaust of a double-acting cylinder leaves a back-pressure cushion that keeps the stroke smooth under varying load.
Adjustment is by a knob under an aluminium locking cap, so a set speed stays set once the cap is tightened. This -S variant replaces the brass throttling column with SUS304 stainless steel, which is the part the air actually flows through, and the D suffix specifies the black finish. The tube side takes 4mm outer diameter soft nylon or polyurethane one-touch tubing; the thread side screws into a 1/8in PT port.
Airtac PSL Throttle Speed Control Fitting PSL401AD-S Technical Specifications
| Model | Airtac PSL Throttle Speed Control Fitting PSL401AD-S |
|---|---|
| Type | Speed controller, threaded elbow |
| Series | PSL |
| Adjustment | Knob with aluminium-alloy locking cap |
| Orientation | Fixed tube direction |
| Body material | Stainless steel 304 (-S variant) |
| Working pressure | 0 - 1.0 MPa (0 - 10 kgf/cm2) |
|---|---|
| Negative pressure | -750 mmHg (10 Torr) |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Applicable tubing | Soft nylon or polyurethane tube |
| Thread standard | PT (Rc tapered) unless the code says otherwise |
POM release button and chuck, aluminium-alloy guide, stainless spring gasket, NBR O-ring; body brass or PBT depending on the part. Stainless (-S): SUS304 throttling column and body parts in place of brass, for copper-free environments. Ratings are unchanged from the standard version. A speed controller is not a shut-off valve - a small leak past a fully closed needle is normal. Close it before applying air, and turn it open slowly. AirTAC publishes flow as a characteristic curve rather than a single figure, so no L/min value is listed.
Model Code: Airtac PSL Throttle Speed Control Fitting PSL401AD-S
| PSL | Speed controller, threaded elbow. |
|---|---|
| 4 / 6 / 8 / 10 / 12 | Tube outside diameter in mm (3.2 mm exists on the mini series). |
| M5 / 01 / 02 / 03 / 04 | Thread: M5x0.8, 1/8", 1/4", 3/8", 1/2" (M3 on the mini series). |
| A / B | A = meter-out (controls flow from the thread port to the tube). B = meter-in. |
| D | Black. Blank = grey. |
| -S | Stainless-steel body. |
Meter-Out or Meter-In?
- check Meter-out (A) is the default. It throttles the air LEAVING the cylinder, so the piston runs against a back-pressure cushion and moves smoothly.
- check Use meter-out on double-acting cylinders - it is the one AirTAC lists as first priority.
- check Meter-in (B) throttles air ENTERING the cylinder. It suits single-acting cylinders and air motors.
- check Meter-in on a double-acting cylinder tends to give a jerky, stick-slip stroke under varying load.
- check Fit the controller at the cylinder port, not at the valve, so the throttled volume is as small as possible.
Where the Airtac PSL Throttle Speed Control Fitting PSL401AD-S Is Used
Mini gripper on a PCB pick-and-place head
A Dia 4 bore matches the small cylinder of an electronics assembly gripper, and meter-out control stops the fingers snapping shut on the component at the end of each cycle.
Dosing cylinder in a laboratory analyser
The SUS304 throttling column suits fluid-handling bench equipment where brass in the wetted air path is unwanted, and fine low-flow adjustment gives a gentle, repeatable dispense stroke.
Camera lift on an optical inspection station
Meter-out throttling lets a compact vision-camera cylinder descend slowly and evenly so the lens settles into focus position without overshoot or bounce.
Is the Airtac PSL Throttle Speed Control Fitting PSL401AD-S the Right Part?
Dia 4 is the smallest tube bore in the entire PSL ladder, so there is no size below it; the closest alternative at the same bore is the M5-threaded version if your manifold offers M5 ports instead of 1/8in. Stepping up at the same 1/8in thread takes you to Dia 6 and then Dia 8, and what changes is capacity: a bigger bore moves more air per revolution of the knob, giving finer average speed control on larger cylinders, while Dia 4 keeps the controlled volume tiny for compact grippers and mini cylinders. Keep the controller mounted directly at the cylinder port so only the small volume of that port is throttled; fitting it back at the valve enlarges the cushioned volume and softens response.
Choose the meter-out A version when a solenoid valve drives a double-acting cylinder and you need a steady, cushioned stroke. Meter-in (the B code) is the better match for single-acting cylinders; running meter-in on a double-acting cylinder invites stick-slip as the load changes.
Quick checklist
- ✓ Tube outside diameter matches exactly
- ✓ Thread size and standard match the port
- ✓ Working pressure within 0 - 1.0 MPa (0 - 10 kgf/cm2)
- ✓ Temperature within -20 to +70 °C
- ✓ Meter-out (A) unless you know you need meter-in
Airtac PSL Throttle Speed Control Fitting PSL401AD-S FAQ
Working pressure 0-1.0 MPa (0-10 kgf/cm2), usable under vacuum to -750 mmHg (10 Torr), proof pressure 1.5 MPa, operating temperature -20 to +70 C. This SKU is the meter-out (A) version with a Dia 4mm tube port and a 1/8in PT thread, finished in black (D suffix), with a SUS304 stainless throttling column in place of brass. It is sized for soft nylon or polyurethane tubing.
No. A speed controller throttles flow for speed setting and will still pass a small leak when fully closed, so it must never be relied on to isolate a circuit. If you need a positive shut-off at a Dia 4 line, fit a dedicated shut-off valve such as the PHV finger valve and keep the PSL401AD-S for speed adjustment only.
Authorized Export Seller
Genuine AirTAC parts produced by AirTAC factory.
1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard parts are processed and dispatched in 3-5 business days.
Fast Reply
Most inquiries answered within 7-8 hours.
Related AirTAC Speed Controllers
Request a Quote for Airtac PSL Throttle Speed Control Fitting PSL401AD-S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.