This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX290S, 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 SI40AX290S
The AirTAC Airtac SI40 Standard Cylinder SI40AX290S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 290mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX290S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke290 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX290S
- 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 SI40AX290S
The AirTAC SI40AX290S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 290mm stroke, and a SUS420J2 stainless piston rod. Delivering 628 N push force at 0.5 MPa via a G1/4 port, its direct replacement is the SAI40AX290S. This current-production SAI model shares the exact same ISO 15552 mounting interface, bore, stroke, and output force, fitting existing fixtures perfectly.
The SAI upgrade features an improved piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family introduces SAIL lock, SAIF valve, and BSAI clamp-lock variants absent in the SI line.
Airtac SI40 Standard Cylinder SI40AX290S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX290S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX290S |
| Bore size | Ø40 mm |
| Stroke | 290 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 SAI40AX290S 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 SAI40AX290S 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 SI40AX290S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×290 | 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 SI40AX290S Is Used
Mid-Force Actuation
Drives 40mm bore clamps and mid-force assembly presses requiring 628 N push at 0.5 MPa.
290mm Transfer Stroke
Executes 290mm linear pushes for diverting components between conveyor lanes.
Stainless Rod Handling
The SUS420J2 rod suits packaging lines needing corrosion resistance against washdowns.
Replacing the Airtac SI40 Standard Cylinder SI40AX290S with the SAI40AX290S
To replace the SI40AX290S, order the SAI40AX290S. Verify the ISO 15552 mounting interface, 40mm bore, 290mm stroke, G1/4 port (PT/G/NPT thread options), and mounting accessory. The -S magnet equates to legacy CS1-B/DS1-B sensors; the SAI replacement uses current AirTAC switches. Sizing both ways: a 50mm bore offers 982 N push at 0.5 MPa, while a 32mm bore yields 402 N. Note that plain cylinders drift without live air; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. At 290mm stroke, guide external rods to prevent side-load bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX290S
- ✓ 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 SI40AX290S FAQ
Yes, the SI40AX290S is discontinued. The direct replacement is the SAI40AX290S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 290mm stroke, force, G1/4 port, and mounting interface.
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. Speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX290S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX290S replacement — usually within 7-8 hours.