This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X775STC, 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 SI40X775STC
The AirTAC Airtac SI40 Standard Cylinder SI40X775STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 775mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X775STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke775 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X775STC
- 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 SI40X775STC
The AirTAC SI40X775STC is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 775mm stroke. Delivering 628N push force at 0.5MPa via a G1/4 port, it is replaced by the SAI40X775STC. This direct successor matches the exact ISO 15552 mounting interface, bore, stroke, force, and TC trunnion mount. The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life.
The SAI family also introduces SAIL, SAIF, and BSAI lock variants absent in the SI line. Your -S magnet works with legacy CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X775STC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X775STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X775STC |
| Bore size | Ø40 mm |
| Stroke | 775 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 SAI40X775STC 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 SAI40X775STC 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 SI40X775STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×775 | 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 SI40X775STC Is Used
Long-Stroke Diversion
Pushes packages across transfer lines using the 775mm stroke, relying on external guides to prevent rod bending during lateral extension.
TC Trunnion Gating
Pivots heavy guard doors or gates using the TC trunnion mount, absorbing pivot stress while cycling at 30-800 mm/s.
Replacing the Airtac SI40 Standard Cylinder SI40X775STC with the SAI40X775STC
To replace the SI40X775STC, order the SAI40X775STC keeping the 40mm bore, 775mm stroke, G1/4 port, and TC trunnion mounting. Confirm your thread option (PT, G, or NPT) and the -S magnet for current AirTAC switches. If you need more force, the 50mm bore offers 982N push at 0.5MPa; if less is acceptable, the 32mm bore provides 402N. Note that a plain cylinder drifts without live air—the cushion only decelerates—so use an external rod lock or pilot check valve for load holding. Because 775mm exceeds 300mm, use an external guide to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X775STC
- ✓ 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 SI40X775STC FAQ
Yes, the SI40X775STC is discontinued. The direct replacement is the SAI40X775STC. It shares the same ISO 15552 mounting interface, 40mm bore, 775mm stroke, output force, G1/4 port, and TC mounting, fitting your existing fixtures perfectly.
This double-acting cylinder has a G1/4 port and M12x1.25 rod thread. It delivers 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a maximum theoretical force of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X775STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X775STC replacement — usually within 7-8 hours.