This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX120S, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SI40 Standard Cylinder SI40AX120S
The AirTAC Airtac SI40 Standard Cylinder SI40AX120S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX120S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX120S
- 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 SI40 Standard Cylinder SI40AX120S
The AirTAC SI40AX120S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 120mm stroke, and a SUS420J2 stainless steel rod. Delivering 628N push force at 0.5MPa via a G1/4 port, it is superseded by the SAI40AX120S direct replacement. This upgrade retains the exact ISO 15552 mounting interface, bore, and output force, fitting existing fixtures perfectly while adding an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life.
The -S suffix indicates a built-in piston magnet for legacy CS1-B/DS1-B sensors. Note that a standard cylinder drifts on air loss; the cushion only decelerates. For load holding, explore the SAIL or BSAI lock variants the SI line lacked, or use an external pilot check valve.
Airtac SI40 Standard Cylinder SI40AX120S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX120S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX120S |
| Bore size | Ø40 mm |
| Stroke | 120 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Adjustable, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI40AX120S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The SAI40AX120S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40AX120S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×120 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SI40 Standard Cylinder SI40AX120S Is Used
Stainless Rod Clamping
Ideal for packaging lines where the SUS420J2 rod resists washdown corrosion while providing 628N of clamping force.
Transfer Diverters
Actuates sorting gates and pushers on conveyors, utilizing the 120mm stroke and adjustable 27mm cushions for smooth stops.
Light Lift Gates
Lifts or lowers light loading bay guides safely, staying within the 32kg vertical lift capacity at 0.5MPa.
Replacing the Airtac SI40 Standard Cylinder SI40AX120S with the SAI40AX120S
To replace the discontinued SI40AX120S, order the SAI40AX120S. Confirm the ISO 15552 mounting interface, 40mm bore, 120mm stroke, G1/4 port (PT/G/NPT thread options), and your specific mounting accessory (LB, FA, TC, etc.). The -S magnet and -A SUS420J2 stainless rod carry over directly. If you need higher force, the neighbouring 50mm bore yields 982N push at 0.5MPa; if downsizing, the 32mm bore provides 402N. For load holding on air loss, remember the cushion only decelerates and cannot hold position—use an external rod lock, a pilot check valve, or the SAI-family SAIL (air-released lock) and BSAI (clamp-lock) variants. The SAIF variant with a built-in 4M valve is also available for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX120S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40AX120S FAQ
Yes, the AirTAC SI40AX120S is discontinued. The direct replacement is the SAI40AX120S. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 120mm stroke, G1/4 port, and mounting interface, but features an upgraded piston seal for longer life.
The 40mm bore uses a G1/4 air port and a 16mm rod. Theoretical forces are: 628N push and 528N pull at 0.5MPa; 879N push at 0.7MPa; 1130N push at 0.9MPa; and a maximum force of 128 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX120S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX120S replacement — usually within 7-8 hours.