This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X500SFA, 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 SI125 Standard Cylinder SI125X500SFA
The AirTAC SI125 Standard Cylinder SI125X500SFA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 500mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X500SFA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke500 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X500SFA
- 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 SI125 Standard Cylinder SI125X500SFA
The AirTAC SI125X500SFA is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore, 500mm stroke, and FA flange mounting. Delivering 6136N push force at 0.5MPa, it is directly replaced by the SAI125X500SFA. This direct upgrade shares the exact G1/2 port, M27x2 rod thread, and ISO 15552 mounting interface.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. It also introduces SAIL and BSAI lock variants absent in the legacy line. The -S magnet supports CS1-B/DS1-B sensors, while a Viton H seal option raises operating temps to 150C.
Airtac SI125 Standard Cylinder SI125X500SFA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X500SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X500SFA |
| Bore size | Ø125 mm |
| Stroke | 500 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125X500SFA carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAI125X500SFA produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125X500SFA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | 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 SI125 Standard Cylinder SI125X500SFA Is Used
Heavy Stamping Press
Drives large platens and stamping dies requiring high 6136N push force over a 500mm travel distance.
Pallet Actuation
Shifts loaded pallets on conveyors where the FA flange mount handles heavy lateral stresses.
Automated Assembly Lift
Raises substantial machinery sub-assemblies, utilizing the 313kg vertical lift capacity safely.
Replacing the Airtac SI125 Standard Cylinder SI125X500SFA with the SAI125X500SFA
To replace the discontinued SI125X500SFA, order the SAI125X500SFA, confirming the FA flange, 500mm stroke, and -S magnet for CS1-B/DS1-B switches. The SAI is dimensionally interchangeable per ISO 15552. Sizing both ways: a 100mm bore yields 3927N at 0.5MPa, while a 160mm bore yields 10053N. At 0.7MPa this 125mm bore pushes 8590N. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for load holding. Because the 500mm stroke is long, use external guides to prevent rod bending and side-load wear. Speed is 30-500mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X500SFA
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125X500SFA FAQ
Yes, the AirTAC SI125X500SFA is discontinued. The direct replacement is the SAI125X500SFA. It shares the same ISO 15552 mounting interface, 125mm bore, 500mm stroke, G1/2 port, and FA flange, fitting existing fixtures perfectly.
It features a G1/2 port and M27x2 rod thread. Force ratings are: 6136N push and 5734N pull at 0.5MPa; 8590N push at 0.7MPa; 11045N push at 0.9MPa; with a theoretical max of 1251kgf at 1.0MPa. Operating speed is 30-500mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X500SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X500SFA replacement — usually within 7-8 hours.