This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX350SH, 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 SI40AX350SH
The AirTAC Airtac SI40 Standard Cylinder SI40AX350SH is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 350mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX350SH, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke350 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX350SH
- 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 SI40AX350SH
The AirTAC SI40AX350SH is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 350mm stroke, G1/4 port, and Viton H high-temperature seals (0-150 C). It delivers 628 N push at 0.5 MPa. AirTAC replaced this EOL unit with the SAI40AX350SH. This direct successor shares the exact ISO 15552 mounting interface, bore, stroke, force, port, and M12x1.25 rod thread, fitting existing fixtures perfectly.
The SAI upgrade features a refined piston seal using two Y-shaped one-way elements for low start-up pressure and extended life. This SI model includes an SUS420J2 stainless rod and a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40AX350SH Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX350SH |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX350SH |
| Bore size | Ø40 mm |
| Stroke | 350 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 SAI40AX350SH 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 SAI40AX350SH 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 SI40AX350SH
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×350 | 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 SI40AX350SH Is Used
Hot Stamp Ejection
Uses the Viton H high-temperature seals and SUS420J2 stainless rod to reliably push finished parts out of heated stamping dies up to 150 C.
Divert Arm Actuation
Provides the 350mm reach needed to sweep packages across adjacent conveyor lanes without requiring complex linkages.
Vertical Gate Control
Lifts lightweight access gates or safety barriers, comfortably handling loads under the 32 kg vertical lift threshold.
Replacing the Airtac SI40 Standard Cylinder SI40AX350SH with the SAI40AX350SH
To replace the SI40AX350SH, order the SAI40AX350SH. Confirm the ISO 15552 mounting interface, 40mm bore, 350mm stroke, G1/4 port, and your specific mounting accessory. The -S magnet enables position sensing (legacy CS1-B/DS1-B; the SAI uses current AirTAC switches), and the -A rod is SUS420J2 stainless. If downsizing, a 32mm bore yields 402 N push at 0.5 MPa; if upsizing, a 50mm bore provides 982 N. Because this is a 350mm stroke, use external guides to prevent rod bending and side-load wear. A plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX350SH
- ✓ 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 SI40AX350SH FAQ
Yes, the SI40AX350SH is discontinued. The direct replacement is the SAI40AX350SH. It is a true ISO 15552 profile cylinder with the identical 40mm bore, 350mm stroke, output force, G1/4 port, and mounting interface, so it drops directly into existing machinery.
The G1/4 port bore delivers a push force of 628 N and a pull force of 528 N at 0.5 MPa. At 0.7 MPa the push force is 879 N, and at 0.9 MPa it is 1130 N. The theoretical maximum force is 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX350SH
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX350SH replacement — usually within 7-8 hours.