This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX900, 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 SI125AX900
The AirTAC SI125 Standard Cylinder SI125AX900 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 900mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX900, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke900 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX900
- 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 SI125AX900
The AirTAC SI125AX900 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 900 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125AX900, matching the exact interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This -A variant uses a SUS420J2 stainless rod. With no -S suffix, this SKU cannot take a sensor.
Airtac SI125 Standard Cylinder SI125AX900 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX900 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX900 |
| Bore size | Ø125 mm |
| Stroke | 900 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 SAI125AX900 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 SAI125AX900 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 SI125AX900
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×900 | 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 SI125AX900 Is Used
Heavy Stamping Press
Drives large heavy-duty stamping actuators where the 6136 N push force at 0.5 MPa handles substantial die resistance reliably.
Pallet Diversion
The 900 mm stroke pushes heavy pallets sideways onto parallel conveyor lines, requiring external guides to prevent rod bending.
Material Lift Gate
Actuates large loading dock gates, utilizing the SUS420J2 stainless rod for corrosion resistance in damp environments.
Replacing the Airtac SI125 Standard Cylinder SI125AX900 with the SAI125AX900
To replace the SI125AX900, order the SAI125AX900. Confirm the ISO 15552 mounting interface, 125 mm bore, 900 mm stroke, G1/2 port, and your specific mounting accessory. This non-magnet SKU cannot accept a CS1-B/DS1-B sensor. The 900 mm stroke requires external guides to prevent rod bending and side-load damage. For sizing, the 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. Note that a plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX900
- ✓ 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 SI125AX900 FAQ
Yes, the SI125AX900 is discontinued. The direct replacement is the SAI125AX900. It is dimensionally interchangeable per ISO 15552, keeping the same 125 mm bore, 900 mm stroke, G1/2 port, and mounting interface.
It features a G1/2 port. 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 max of 1251 kgf at 1.0 MPa. Speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX900
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX900 replacement — usually within 7-8 hours.