This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX65S, 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 SI40AX65S
The AirTAC SI40 Standard Cylinder SI40AX65S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 65mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX65S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke65 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX65S
- 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 SI40AX65S
The AirTAC SI40AX65S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 65mm stroke, and a SUS420J2 stainless steel piston rod. Delivering 628N push and 528N pull at 0.5MPa, it features a G1/4 air port, M12x1.25 rod thread, and a built-in piston magnet for legacy CS1-B/DS1-B switches. AirTAC replaced this legacy unit with the SAI40AX65S, a direct replacement retaining the exact ISO 15552 mounting interface, bore, stroke, force, and port size.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life, while the SAI family adds SAIL, SAIF, and BSAI lock or valve variants the SI lacked. The standard cylinder operates at 30-800mm/s, and if you need heat resistance, a Viton H seal option raises the operating range to 0-150C.
Airtac SI40 Standard Cylinder SI40AX65S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX65S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX65S |
| Bore size | Ø40 mm |
| Stroke | 65 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 SAI40AX65S 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 SAI40AX65S 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 SI40AX65S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×65 | 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 SI40AX65S Is Used
Compact Part Ejection
Uses the 628N push force at 0.5MPa to eject small machined components from a fixture, leveraging the 65mm stroke for rapid cycling.
Package Diverting
Actuates a diverting gate on a packaging line, where the 32kg vertical lift capacity and 30-800mm/s speed provide reliable sorting momentum.
Stainless Rod Clamping
Secures parts in humid wash-down environments using the SUS420J2 stainless rod option, preventing corrosion while maintaining clamping pressure.
Replacing the Airtac SI40 Standard Cylinder SI40AX65S with the SAI40AX65S
To replace the discontinued SI40AX65S, order the SAI40AX65S. Confirm the ISO 15552 mounting interface, 65mm stroke, G1/4 port (PT/G/NPT thread options), and your mounting accessory (LB, FA, FB, TC, etc.). The -S denotes a piston magnet for position sensing; the legacy SI used CS1-B/DS1-B switches, while the SAI takes current AirTAC sensors. The -A rod is SUS420J2 stainless steel for corrosion resistance versus the default carbon steel. Sizing both ways: the 40mm bore yields 628N push at 0.5MPa; if less force is needed, a 32mm bore provides 402N, or step up to a 50mm bore for 982N. Note that a plain cylinder does not hold load on air loss—the cushion only decelerates. For load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants. At 65mm stroke, side-load and rod-bending risks are minimal, so no external guide is strictly required.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX65S
- ✓ 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 SI40AX65S FAQ
Yes, the SI40AX65S is discontinued. The direct replacement is the AirTAC SAI40AX65S. It features the same ISO 15552 mounting interface, 40mm bore, 65mm stroke, output force, G1/4 port, and mounting accessories, fitting directly into existing fixtures.
The 40mm bore features a G1/4 air port and M12x1.25 rod thread. Force output is 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX65S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX65S replacement — usually within 7-8 hours.