This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X750FA, 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 SI125X750FA
The AirTAC Airtac SI125 Standard Cylinder SI125X750FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 750mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X750FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke750 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X750FA
- 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 SI125X750FA
The AirTAC SI125X750FA is a discontinued double-acting ISO 15552 profile cylinder with an FA flange mount, delivering 6136 N push force at 0.5 MPa. AirTAC replaced it with the SAI125X750FA, a direct upgrade retaining the exact 125 mm bore, 750 mm stroke, G1/2 port, and ISO 15552 mounting interface. This SKU lacks a magnet and cannot accept a sensor.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. For applications needing load holding, the SAI family introduces SAIL and BSAI lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125X750FA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X750FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X750FA |
| Bore size | Ø125 mm |
| Stroke | 750 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 SAI125X750FA 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 SAI125X750FA 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 SI125X750FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×750 | 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 SI125X750FA Is Used
Heavy Press Staging
Ideal for positioning heavy steel blanks into large stamping presses, using the FA flange to handle the 313 kg vertical lift capacity at 0.5 MPa.
Pallet Diversion
Drives robust routing arms on high-mass pallet conveyors, relying on the 40 mm adjustable air cushions to decelerate the 750 mm stroke safely.
Automated Warehousing
Actuates large load-lifting mechanisms in automated storage systems, requiring external guides to manage the side loads over the extended stroke.
Replacing the Airtac SI125 Standard Cylinder SI125X750FA with the SAI125X750FA
To replace the SI125X750FA, order the SAI125X750FA. It drops directly into existing fixtures via the ISO 15552 FA flange interface, matching the 125 mm bore, 750 mm stroke, and G1/2 port. If sizing up or down, neighboring bores are 100 mm and 160 mm; at 0.5 MPa, this bore yields 6136 N push and 5734 N pull. Because this is a plain cylinder without a magnet, it cannot use CS1-B/DS1-B sensors. The 750 mm stroke demands external guides to prevent rod bending and side-load wear. Finally, the air cushion only decelerates the piston near stroke end—it will not hold a load on air loss; for that, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X750FA
- ✓ 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 SI125X750FA FAQ
Yes, the SI125X750FA is discontinued. The direct replacement is the AirTAC SAI125X750FA. It features the same ISO 15552 FA flange mounting interface, 125 mm bore, 750 mm stroke, output force, and G1/2 port, fitting existing fixtures perfectly.
It has a G1/2 port. The force 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 of 1251 kgf at 1.0 MPa. The operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X750FA
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