This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X500SFA, 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 SI40X500SFA
The AirTAC Airtac SI40 Standard Cylinder SI40X500SFA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X500SFA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X500SFA
- 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 SI40X500SFA
The AirTAC SI40X500SFA is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 500mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X500SFA, a direct sharing the exact same interface, force, and mounting.
The SAI upgrade features a new piston seal using 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.
Airtac SI40 Standard Cylinder SI40X500SFA Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X500SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X500SFA |
| Bore size | Ø40 mm |
| Stroke | 500 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 SAI40X500SFA 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 SAI40X500SFA 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 SI40X500SFA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×500 | 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 SI40X500SFA Is Used
Long-Stroke Diverting
Pushes packages across a 500mm conveyor lane using the 628N force class, guided externally to prevent rod bending.
Pneumatic Ejector
Ejects machined parts from a fixture, utilizing the adjustable 27mm air cushions to decelerate the 16mm rod at stroke ends.
Replacing the Airtac SI40 Standard Cylinder SI40X500SFA with the SAI40X500SFA
To replace the SI40X500SFA, order the SAI40X500SFA. Confirm the ISO 15552 FA flange mounting, 40mm bore, 500mm stroke, G1/4 port, and the -S magnet for legacy CS1-B/DS1-B sensors. If you need more force, the neighboring 50mm bore yields 982N push at 0.5MPa; if less is acceptable, the 32mm bore provides 402N. Because this is a 500mm stroke, use an external guide to prevent rod bending and side-load wear. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X500SFA
- ✓ 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 SI40X500SFA FAQ
Yes, the SI40X500SFA is discontinued. The direct replacement is the SAI40X500SFA. It shares the identical ISO 15552 mounting interface, 40mm bore, 500mm stroke, force, and G1/4 port, fitting existing fixtures perfectly.
The G1/4 port feeds a 40mm bore that generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, and a theoretical maximum of 128kgf at 1.0MPa. It operates at 30-800mm/s with a 16mm rod and M12x1.25 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X500SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X500SFA replacement — usually within 7-8 hours.