This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X950S, 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 SI40X950S
The AirTAC Airtac SI40 Standard Cylinder SI40X950S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 950mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X950S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke950 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X950S
- 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 SI40X950S
The AirTAC SI40X950S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 950 mm stroke. It delivers 628 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X950S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family expands options with SAIL, SAIF, and BSAI variants.
Airtac SI40 Standard Cylinder SI40X950S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X950S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X950S |
| Bore size | Ø40 mm |
| Stroke | 950 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 SAI40X950S 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 SAI40X950S 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 SI40X950S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×950 | 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 SI40X950S Is Used
Long-Stroke Diversion
Pushes packages across a transfer lane with a 950 mm reach, relying on the 628 N push force at 0.5 MPa to overcome friction.
Automated Gate Control
Actuates safety gates on machinery, using the G1/4 port and adjustable 27 mm air cushions to decelerate smoothly at stroke ends.
Replacing the Airtac SI40 Standard Cylinder SI40X950S with the SAI40X950S
To replace the SI40X950S, order the SAI40X950S. Verify your ISO 15552 mounting accessories (LB, FA, FB, CA, CB, TC), the G1/4 port, and the M12x1.25 rod thread. The SAI family also adds SAIL (air-released lock), SAIF (built-in 4M valve), and BSAI (clamp-lock) variants if your application requires load holding, as a plain cylinder drifts without live air and its cushion only decelerates. Because the 950 mm stroke exceeds 300 mm, use an external guide to prevent rod bending and side-load damage. If you need more force, the neighbouring 50 mm bore yields 982 N push at 0.5 MPa; if less is required, the 32 mm bore offers 402 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X950S
- ✓ 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 SI40X950S FAQ
Yes, the SI40X950S is discontinued. The direct replacement is the SAI40X950S. It shares the same ISO 15552 mounting interface, 40 mm bore, 950 mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
The 40 mm bore provides a push force of 628 N and a pull force of 528 N at 0.5 MPa. At 0.7 MPa it pushes 879 N, and 1130 N at 0.9 MPa. The theoretical maximum is 128 kgf at 1.0 MPa, with an operating speed of 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X950S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X950S replacement — usually within 7-8 hours.