Airtac PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD
The AirTAC Airtac PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD is a genuine universal speed controller with knob with aluminium-alloy locking cap and 360 degree adjustable tube direction, used to set the speed of a pneumatic cylinder by throttling its air.
- TypeUniversal speed controller
- SeriesPSS
- 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 PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD
The AirTAC PSS1204BD is a universal (360 degree swivel) speed controller that sets actuator speed by throttling air in one direction while letting it pass freely the other way. The B suffix makes this a meter-in unit: air flowing from the 1/2in PT thread port into the Dia 12 tube runs free, and the flow on the return path is controlled. The handle is marked B. Meter-in is the right choice for a single-acting, spring-return cylinder, where you want to throttle the exhaust so the spring controls the return speed. AirTAC's own guidance is that meter-out (the A version) is the first priority for double-acting cylinders, because a meter-in throttle on a double-acting bore can stick-slip as the load changes.
Adjustment is a knob with an aluminium-alloy locking cap, so a setting survives machine vibration until someone deliberately unlocks it. Inside, a brass throttling column meters the flow through a brass body, with the holder moulded in PBT and an NBR O-ring sealing the interface. The D suffix means the body is finished in black rather than the standard grey. Because this is the PSS universal body, the Dia 12 tube fitting swivels a full turn, which matters at this bore size: a 12mm line is stiff, and the swivel takes the twisting load off the tubing instead of transferring it to the seal.
Airtac PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD Technical Specifications
| Model | Airtac PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD |
|---|---|
| Type | Universal speed controller |
| Series | PSS |
| Adjustment | Knob with aluminium-alloy locking cap |
| Orientation | 360 degree adjustable 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 PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD
| PSS | Universal speed controller. |
|---|---|
| 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 PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD Is Used
Spring-return clamp on a packaging head
A single-acting clamp closing onto a printed carton must not slap the board. Metering the exhaust on the B circuit lets the spring pull the pad home gently while the free forward stroke keeps cycle time short.
Kicker arm diverting cartons off a conveyor
A 12mm-bore kicker cylinder on a distribution line needs a fast kick out and a controlled retract so the next carton is not knocked sideways. The swivel fitting copes with the angled run to the actuator.
Bench rig for actuator cycle testing
Test stands swap actuators constantly and the plumbing angle changes with every one. A 1/2in PT thread with a 360 degree tube swivel lets technicians re-route stiff 12mm lines without unscrewing the body.
Is the Airtac PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD the Right Part?
This is the top of the PSS ladder. At the 1/2in thread, Dia 12 is the only tube size AirTAC offers, so there is no smaller tube on this port - if your cylinder port is 1/2in and your line is 12mm, this is the part. To step down, you drop the thread first: the PSS1203B keeps the same Dia 12 tube on a 3/8in PT thread, and the next tube size down, Dia 10, exists only on the 3/8in and 1/4in threads (PSS1003B). A smaller bore costs you flow capacity and stiffens the response on long strokes; stepping up is not possible from here.
Choose PSS over the fixed-direction PSL when the line arrives at an angle or the fitting has to rotate during setup - the swivel spares you an elbow fitting. Whichever body you pick, mount the controller directly at the cylinder port so the throttled air volume stays small and the speed response stays crisp. This is a flow control, not a shut-off: it leaks slightly when fully closed, so isolate the circuit elsewhere.
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 PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD FAQ
Working pressure 0-1.0 MPa (0-10 kgf/cm2), proof pressure 1.5 MPa, negative pressure -750 mmHg (10 Torr), and an operating temperature of -20 to +70 C. This SKU is the Dia 12 tube size with a 1/2in PT thread, meter-in (B) control, finished in black via the D suffix. The tube fitting swivels 360 degrees.
The PSS body swivels 360 degrees at the tube fitting, so stiff 12mm polyurethane or nylon line does not twist the seal when the run is not perfectly straight - the PSL locks the tube in one fixed direction. Adjustment style is identical: a knob with a locking aluminium cap. Just confirm the control method, since the meter-in B shown here behaves differently in circuit to a meter-out A.
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 PSS Exhaust Throttle Type Universal Speed Control Valve PSS1204BD
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.