This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX900S, 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 SI40AX900S
The AirTAC Airtac SI40 Standard Cylinder SI40AX900S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 900mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX900S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke900 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX900S
- 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 SI40AX900S
The AirTAC SI40AX900S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 900mm stroke. Delivering 628N push force at 0.5MPa, it features a SUS420J2 stainless rod, a G1/4 port, and a built-in magnet for CS1-B/DS1-B sensors. The direct replacement is the SAI40AX900S, which shares the same interface, force, and porting.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent in the SI line.
Airtac SI40 Standard Cylinder SI40AX900S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX900S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX900S |
| Bore size | Ø40 mm |
| Stroke | 900 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 SAI40AX900S 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 SAI40AX900S 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 SI40AX900S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×900 | 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 SI40AX900S Is Used
Pneumatic Press Ejection
Cycles finished parts out of a light-duty press at 30-800 mm/s, requiring external guides to manage the 900mm stroke side loads.
Replacing the Airtac SI40 Standard Cylinder SI40AX900S with the SAI40AX900S
To replace the SI40AX900S, order the SAI40AX900S. Confirm the ISO 15552 mounting interface, 40mm bore, 900mm stroke, G1/4 port, and the -S magnet for current AirTAC switches. If downsizing, a 32mm bore yields 402N at 0.5MPa; if uprating, a 50mm bore provides 982N. Because this is a 900mm stroke, use an external guide to prevent rod bending and side-load wear. A plain cylinder drifts on air loss—the cushion only decelerates—so use a pilot check valve or the SAIL/BSAI lock variant for load holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX900S
- ✓ 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 SI40AX900S FAQ
Yes, the SI40AX900S is discontinued. The direct replacement is the SAI40AX900S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 900mm stroke, 628N force, and G1/4 port for existing fixtures.
The 40mm bore provides 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a maximum theoretical force of 128kgf at 1.0MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX900S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX900S replacement — usually within 7-8 hours.