This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X100FB, 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 SI125X100FB
The AirTAC Airtac SI125 Standard Cylinder SI125X100FB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 100mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X100FB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke100 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X100FB
- 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 SI125X100FB
The AirTAC SI125X100FB is a discontinued double-acting ISO 15552 profile cylinder with an FB flange mount. Built for heavy-duty tasks, it delivers 6136 N push and 5734 N pull at 0.5 MPa through a 125 mm bore. The direct replacement is the SAI125X100FB, matching the G1/2 port, M27x2 thread, and 100 mm stroke.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. Note this SKU lacks a magnet (-S), so it cannot accept CS1-B/DS1-B sensors. For high heat, Viton H seals raise the limit to 150 C.
Airtac SI125 Standard Cylinder SI125X100FB Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X100FB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X100FB |
| Bore size | Ø125 mm |
| Stroke | 100 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 SAI125X100FB 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 SAI125X100FB 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 SI125X100FB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×100 | 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 SI125X100FB Is Used
Heavy Press Clamping
Secures large steel plates in a hydraulic press fixture, utilizing the 6136 N push force at 0.5 MPa to prevent workpiece shifting during machining.
Mold Ejection Systems
Drives the ejection stage of large injection molding machinery, relying on the 40 mm adjustable air cushions to decelerate the 32 mm rod smoothly.
Replacing the Airtac SI125 Standard Cylinder SI125X100FB with the SAI125X100FB
To replace the SI125X100FB, order the SAI125X100FB. Verify the ISO 15552 interface, 125 mm bore, 100 mm stroke, G1/2 port, and FB flange. This non-magnetic SKU cannot support position sensing; order an SAI variant with -S if switches are needed. Sizing both ways: a 100 mm bore yields 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. The cushion only decelerates; it does not hold load on air loss. For load holding, use an external pilot check valve, rod lock, or the SAIL/BSAI lock variants. Speed is 30-500 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X100FB
- ✓ 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 SI125X100FB FAQ
Yes, the AirTAC SI125X100FB is discontinued. The direct replacement is the SAI125X100FB. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 100 mm stroke, FB flange mount, G1/2 port, and 6136 N output force.
The 125 mm bore uses a G1/2 port. It generates 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 maximum theoretical force of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X100FB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X100FB replacement — usually within 7-8 hours.