Airtac PSL Throttle Speed Control Fitting PSL804A-S
SUS304 stainless variant (-S)The AirTAC Airtac PSL Throttle Speed Control Fitting PSL804A-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 PSL804A-S
The PSL804A-S is a stainless speed controller that screws into a 1/2in PT port and accepts Dia 8mm soft nylon or polyurethane tubing. Suffix A means meter-out: air flowing from the thread port to the tube is throttled by the adjustable needle, while the return path runs free. Throttling the exhaust of a double-acting cylinder leaves a back-pressure cushion, so the stroke stays smooth and does not stick-slip under varying load - which is why AirTAC calls meter-out the first priority choice.
This -S build carries a SUS304 stainless throttling column in place of the standard brass column, with a stainless spring gasket, so it suits circuits that get hosed down or exposed to corrosive media. Adjustment is a knob with an aluminium locking cap: set the speed, then tighten the cap so vibration cannot drift the setting. Note the port and tube pairing - a 1/2in thread with an 8mm bore means the tube, not the thread, sets the flow capacity of the circuit.
Airtac PSL Throttle Speed Control Fitting PSL804A-S Technical Specifications
| Model | Airtac PSL Throttle Speed Control Fitting PSL804A-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 PSL804A-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 PSL804A-S Is Used
Plating line lift cylinder
On electroplating and pickling lines, jigs are lifted out of acid baths at a controlled pace. The SUS304 throttling column replaces brass where copper ions would contaminate the bath chemistry, while meter-out control stops the loaded jig dropping fast when the valve exhausts.
Wash-down conveyor gate
A gate cylinder on a meat or dairy packing conveyor gets hosed down every shift. The stainless column and gasket resist the wash, and the aluminium locking cap holds the gate speed setting despite daily water jets and vibration.
Dockside hold-down clamp
Trailers are clamped at a marine or coastal loading bay where salt air attacks brass quickly. A 1/2in PT port suits the larger control valve on the clamp circuit, with Dia 8 tubing routed to the clamp cylinder and meter-out control easing the clamp onto the chassis.
Is the Airtac PSL Throttle Speed Control Fitting PSL804A-S the Right Part?
You are at the bottom of the 1/2in ladder. Within the PSL 1/2in family only Dia 10 (PSL1004A-S) and Dia 12 (PSL124A-S) exist above this Dia 8 part, and stepping up buys you more free-flow capacity for bigger cylinder bores. If your cylinder is a smaller compact unit, the same Dia 8 tube also exists on 1/4in and 3/8in threads (PSL802A-S, PSL803A-S) - choose whichever thread matches your valve or cylinder port.
Mount the controller directly in the cylinder port rather than at the valve, so only the short stub of tubing between controller and cylinder is throttled and response stays crisp. Remember this is a flow control, not a shut-off: a speed controller deliberately leaks slightly when fully closed, so never use it to isolate a circuit.
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 PSL804A-S FAQ
Working pressure 0-1.0 MPa (0-10 kgf/cm2), proof pressure 1.5 MPa, usable vacuum to -750 mmHg (10 Torr), operating temperature -20 to +70 C. It takes Dia 8mm soft nylon or polyurethane tubing on a 1/2in PT thread and is meter-out (suffix A). The stainless build changes the throttling column and spring gasket to SUS304; all pressure, vacuum and temperature ratings are identical to the standard PSL804A.
Yes. The dimension tables match the standard part exactly, and the PT thread is the same taper pattern, so seal with PTFE tape or thread sealant as usual - do not let tape shreds enter the throttling needle. The only construction difference is the SUS304 throttling column and stainless spring gasket in place of brass; the knob, locking cap and A/B control logic are unchanged.
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 PSL804A-S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.