This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X280FA, 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 SI125X280FA
The AirTAC SI125 Standard Cylinder SI125X280FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 280mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X280FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke280 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X280FA
- 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 SI125X280FA
The AirTAC SI125X280FA is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 280 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. AirTAC replaced this legacy unit with the SAI125X280FA, a direct upgrade sharing the exact same FA flange mounting, M27x2 rod thread, and output force.
The SAI125X280FA features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this specific SKU lacks a magnet (-S), so it cannot accept CS1-B or DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X280FA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X280FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X280FA |
| Bore size | Ø125 mm |
| Stroke | 280 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 SAI125X280FA 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 SAI125X280FA 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 SI125X280FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×280 | 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 SI125X280FA Is Used
Heavy-Duty Pressing
Ideal for applying high clamping forces in metalworking and assembly lines, utilizing the 6136 N push force at 0.5 MPa to seat bearings and form components securely.
Pallet Handling
Drives robust lifting and positioning mechanisms in automated storage systems, where the 313 kg vertical lift capacity handles substantial packaged loads efficiently.
Large Fixture Actuation
Moves heavy tooling and fixtures on manufacturing floors, relying on the rigid FA flange mount and ISO 15552 profile barrel to maintain alignment under stress.
Replacing the Airtac SI125 Standard Cylinder SI125X280FA with the SAI125X280FA
To replace the SI125X280FA, order the SAI125X280FA. It is dimensionally interchangeable per the ISO 15552 mounting interface, matching the 125 mm bore, 280 mm stroke, G1/2 port, and FA flange accessory. Because this SKU has no magnet, it cannot support position sensing; if switches are needed, select an SAI125X280FAS. When sizing, neighbouring bores offer alternatives: the 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore provides 10053 N. A plain cylinder drifts on air loss, as the 40 mm adjustable air cushion only decelerates near stroke end. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Since the 280 mm stroke exceeds 300 mm, ensure guide rails to prevent rod bending under side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X280FA
- ✓ 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 SI125X280FA FAQ
Yes, the AirTAC SI125X280FA is discontinued. The direct replacement is the SAI125X280FA. It shares the identical ISO 15552 mounting interface, 125 mm bore, 280 mm stroke, G1/2 port, and FA flange, fitting directly into existing fixtures.
This 125 mm bore cylinder uses a G1/2 air port. The thrust ratings are: 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical maximum force of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X280FA
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