This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X446S, 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 SI40X446S
The AirTAC Airtac SI40 Standard Cylinder SI40X446S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 446mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X446S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke446 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X446S
- 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 SI40X446S
The AirTAC SI40X446S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 446mm stroke. It delivers 628 N push and 528 N pull at 0.5 MPa, operating via a G1/4 port. The direct replacement is the SAI40X446S, matching the bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. The SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked. This -S model uses CS1-B/DS1-B sensors; SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X446S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X446S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X446S |
| Bore size | Ø40 mm |
| Stroke | 446 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 SAI40X446S 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 SAI40X446S 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 SI40X446S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×446 | 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 SI40X446S Is Used
Material Diversion
Actuates routing gates on package lines, using the 628 N push force to redirect totes reliably at speed.
Clamp Actuation
Provides 446mm travel to position and clamp workpieces in machining cells before the cutting cycle begins.
Replacing the Airtac SI40 Standard Cylinder SI40X446S with the SAI40X446S
To replace the SI40X446S, order the SAI40X446S, confirming the ISO 15552 interface, 40mm bore, 446mm stroke, G1/4 port (PT/G/NPT), mounting accessory, and the -S magnet. For sizing both ways: a 32mm bore yields 402 N [email protected], while a 50mm bore yields 982 N. At 0.7 MPa this 40mm bore pushes 879 N. Because stroke is 446mm, 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 rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X446S
- ✓ 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 SI40X446S FAQ
Yes, the SI40X446S is discontinued. The direct replacement is the SAI40X446S. It shares the identical ISO 15552 mounting interface, 40mm bore, 446mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
The 40mm bore uses a G1/4 port. Force output is 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 theoretical max of 128 kgf at 1.0 MPa. It features a 16mm rod and M12x1.25 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X446S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X446S replacement — usually within 7-8 hours.