This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX280S, 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 SI40AX280S
The AirTAC Airtac SI40 Standard Cylinder SI40AX280S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 280mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX280S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke280 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX280S
- 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 SI40AX280S
The AirTAC SI40AX280S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 280mm stroke, and a SUS420J2 stainless steel piston rod. It delivers 628 N push and 528 N pull at 0.5 MPa. AirTAC replaced this legacy unit with the SAI40AX280S, a direct sharing the same G1/4 port, M12x1.25 thread, and ISO 15552 mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI40 Standard Cylinder SI40AX280S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX280S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX280S |
| Bore size | Ø40 mm |
| Stroke | 280 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 SAI40AX280S 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 SAI40AX280S 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 SI40AX280S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×280 | 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 SI40AX280S Is Used
Diverting Gate Actuation
Drives routing flaps on packaging lines using the 528 N pull force at 0.5 MPa, with the SUS420J2 rod resisting washdown moisture.
Clamp Positioning
Moves lightweight tooling or clamps into place over a 280mm travel distance, relying on adjustable 27mm air cushions for smooth stops.
Replacing the Airtac SI40 Standard Cylinder SI40AX280S with the SAI40AX280S
To replace the SI40AX280S, order the SAI40AX280S. Confirm the ISO 15552 mounting interface, 40mm bore, 280mm stroke, G1/4 port, and the -A SUS420J2 rod. Because this is a 280mm stroke, verify guide alignment to prevent rod bending under side loads. If sizing up or down, neighbouring bores are 32mm (402 N push @0.5 MPa) and 50mm (982 N push @0.5 MPa). Note that a plain cylinder drifts on air loss; the air cushion only decelerates. For load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX280S
- ✓ 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 SI40AX280S FAQ
Yes, the AirTAC SI40AX280S is discontinued. The direct replacement is the SAI40AX280S. It shares the identical ISO 15552 mounting interface, 40mm bore, 280mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
This 40mm bore cylinder has a G1/4 air port. It generates 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a theoretical maximum force of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX280S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX280S replacement — usually within 7-8 hours.