Airtac PSL Throttle Speed Control Fitting PSL401AD
The AirTAC Airtac PSL Throttle Speed Control Fitting PSL401AD 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
The PSL401AD is a meter-out speed controller that screws into a 1/8in PT port and grips 4mm outside diameter soft nylon or polyurethane tubing. Air flowing from the thread port out through the tube is throttled by the adjusting knob, while air returning the other way passes freely, so the actuator exhaust is restricted and the stroke stays smooth under load. AirTAC rates meter-out as the first-choice control method because the trapped back-pressure cushions a double-acting cylinder instead of letting it lurch.
This code carries the A suffix and its cap is marked A, confirming meter-out. The D suffix makes the body black instead of the standard grey; every other detail, including the aluminium-alloy locking cap that stops the setting drifting under machine vibration, is unchanged. Dia 4 is the smallest tube bore offered on any PSL, which is exactly why it appears here: it suits miniature cylinders and grippers where a few extra cubic millimetres of throttled air is all the control you need.
Airtac PSL Throttle Speed Control Fitting PSL401AD Technical Specifications
| Model | Airtac PSL Throttle Speed Control Fitting PSL401AD |
|---|---|
| Type | Speed controller, threaded elbow |
| Series | PSL |
| Adjustment | Knob with aluminium-alloy locking cap |
| Orientation | Fixed tube direction |
| 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. 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
| 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. |
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 Is Used
Miniature pick-and-place gripper
A small parallel gripper on a PCB handling robot closes hard enough to crack components if it is left wide open. Metering the exhaust at the gripper port with this Dia 4 controller softens the close without slowing the release stroke.
Vial capping head on a lab bench
A compact 10mm-bore capping cylinder must lower a crimping head gently onto a glass vial. This 1/8in meter-out controller in the black D finish suits the small-bore tubing and restrained motion a benchtop instrument needs.
Dosing pusher inside a packaging machine
A short-stroke pusher that spoons product into blister pockets has to index steadily rather than slam. Throttling the exhaust at the port with a PSL401AD lets the machine builder trim the stroke time without stick-slip.
Is the Airtac PSL Throttle Speed Control Fitting PSL401AD the Right Part?
Size both ways before you buy. Downwards there is nothing: Dia 4 is the smallest tube in the PSL 1/8in ladder, so this is the floor of the range. Upwards, PSL601A takes the same 1/8in thread on 6mm tube and gives you more free-flow capacity for a larger bore. Note that on 1/4in threads the ladder starts at Dia 6, so staying with 4mm tubing means either this part or the same tube on an M5 thread; stepping up to 1/4in forces you to 6mm tube as well.
A fixed-body PSL like this is the right pick when the tube runs one way to the cylinder and will not need to rotate. Fit the controller directly at the cylinder port rather than back at the valve, because only the small volume of air between the throttle and the chamber is then metered and response stays crisp. Remember a speed controller is not a shut-off valve: it weeps slightly when fully closed, so use a PHV finger valve where you genuinely need isolation.
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 FAQ
It is a PSL meter-out speed controller for Dia 4 tube on a 1/8in PT thread. Working pressure is 0-1.0 MPa (0-10 kgf/cm2), proof pressure 1.5 MPa, negative pressure down to -750 mmHg (10 Torr) and temperature -20 to +70 C. It is intended for soft nylon or polyurethane tubing and the D suffix denotes a black body rather than the standard grey.
Meter-out throttles the air leaving the cylinder, so the chamber holds back-pressure and the piston is cushioned through the stroke. That keeps a double-acting cylinder smooth even when the load varies. Meter-in (B) control is mainly for single-acting cylinders; on a double-acting cylinder under changing load it tends to stick-slip, which is why AirTAC names meter-out the first priority.
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
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.