This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X770S, 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 SI40X770S
The AirTAC Airtac SI40 Standard Cylinder SI40X770S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 770mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X770S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke770 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X770S
- 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 SI40X770S
The AirTAC SI40X770S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 770 mm stroke, delivering 628 N push force at 0.5 MPa via its G1/4 port. AirTAC replaced this legacy unit with the SAI40X770S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI successor features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The -S suffix indicates a built-in piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family introduces SAIL, SAIF, and BSAI lock and valve variants the original SI line lacked.
Airtac SI40 Standard Cylinder SI40X770S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X770S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X770S |
| Bore size | Ø40 mm |
| Stroke | 770 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 SAI40X770S 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 SAI40X770S 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 SI40X770S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×770 | 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 SI40X770S Is Used
Material Diversion
Actuates routing gates on packaging lines, utilizing the 628 N push force to redirect totes at 30-800 mm/s operating speeds.
Long-Stroke Pushing
Transfers products between conveyor zones across a 770 mm gap, requiring external guide rods to prevent piston bending.
Replacing the Airtac SI40 Standard Cylinder SI40X770S with the SAI40X770S
To replace the SI40X770S, order the SAI40X770S and confirm the ISO 15552 mounting interface, 40 mm bore, 770 mm stroke, G1/4 port (PT/G/NPT thread), and mounting accessory. Retain the -S magnet for current AirTAC switch compatibility. Sizing both ways: a 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. Note that a 770 mm stroke demands external guide support to prevent rod bending and excessive side loads. For load holding on air loss, add an external rod lock or pilot check valve, as the cushion only decelerates.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X770S
- ✓ 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 SI40X770S FAQ
Yes, the SI40X770S is discontinued. The direct replacement is the SAI40X770S. It shares the identical ISO 15552 mounting interface, 40 mm bore, 770 mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
This double-acting cylinder features a 16 mm rod, M12x1.25 thread, 27 mm cushions, and a G1/4 port. Force ratings are 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 maximum theoretical force of 128 kgf at 1.0 MPa. Speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X770S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X770S replacement — usually within 7-8 hours.