This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX900, 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 SI40AX900
The AirTAC Airtac SI40 Standard Cylinder SI40AX900 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 SAI40AX900, 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 → SAI40AX900
- 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 SI40AX900
The AirTAC SI40AX900 is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 900mm stroke, G1/4 port, and M12x1.25 rod thread. It delivers 628 N push force at 0.5 MPa. AirTAC replaced this legacy unit with the SAI40AX900, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, and port size.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The -A suffix specifies a SUS420J2 stainless steel rod for corrosion resistance. Without a -S suffix, this SKU cannot accept a magnetic switch.
Airtac SI40 Standard Cylinder SI40AX900 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX900 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX900 |
| 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 SAI40AX900 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 SAI40AX900 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 SI40AX900
| 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 SI40AX900 Is Used
Long-Stroke Diversion
Pushes packages across a 900mm conveyor lane using the 628 N thrust at 0.5 MPa, requiring external guides to prevent rod bending over the extended travel.
Actuator Positioning
Shifts a tooling carriage 900mm along an assembly line; the 27mm adjustable air cushions decelerate the payload smoothly at stroke ends.
Replacing the Airtac SI40 Standard Cylinder SI40AX900 with the SAI40AX900
To replace the SI40AX900, order the SAI40AX900. Verify your ISO 15552 mounting fixtures, G1/4 port, and M12x1.25 thread. Because this 900mm stroke is long, use external guides to prevent rod bending and side-load wear. If sizing up or down, neighboring bores are 32mm (402 N @0.5 MPa) and 50mm (982 N @0.5 MPa). Note that a plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. The SAIF variant adds a built-in valve if needed.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX900
- ✓ 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 SI40AX900 FAQ
Yes, the SI40AX900 is discontinued. The direct replacement is the SAI40AX900. It shares the same ISO 15552 mounting interface, 40mm bore, 900mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly while adding an upgraded piston seal.
The G1/4 port bore delivers 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 max of 128 kgf at 1.0 MPa. It operates at 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX900
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX900 replacement — usually within 7-8 hours.