This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX290S, 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 SI125AX290S
The AirTAC SI125 Standard Cylinder SI125AX290S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 290mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX290S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke290 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX290S
- 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 SI125AX290S
The AirTAC SI125AX290S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore, 290mm stroke, G1/2 port, and M27x2 rod thread. Delivering 6136 N push force at 0.5 MPa, it is replaced by the direct replacement SAI125AX290S.
The SAI upgrade retains identical dimensions and force but adds a two Y-shaped one-way piston seal for low start-up pressure. The -A suffix specifies a SUS420J2 stainless rod, while the -S magnet works with legacy CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125AX290S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX290S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX290S |
| Bore size | Ø125 mm |
| Stroke | 290 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 SAI125AX290S 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 SAI125AX290S 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 SI125AX290S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×290 | 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 SI125AX290S Is Used
Heavy-Duty Pressing
Applies up to 11045 N of push force at 0.9 MPa for seating large bearings or forming heavy gauge metal components.
Logistics Diversion
Actuates heavy lane diverters and sorting arms on high-throughput packaging lines with a 290mm travel distance.
Replacing the Airtac SI125 Standard Cylinder SI125AX290S with the SAI125AX290S
To replace the SI125AX290S, order the SAI125AX290S. Verify the ISO 15552 mounting interface, 125mm bore, 290mm stroke, G1/2 port (PT/G/NPT), and mounting accessory. The -S magnet enables CS1-B/DS1-B sensors, while -A indicates the SUS420J2 rod. Sizing both ways: a 100mm bore yields 3927 N push at 0.5 MPa, and a 160mm bore yields 10053 N. For this 290mm stroke, use a guide to prevent rod bending under side loads. This plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Speed is 30-500 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX290S
- ✓ 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 SI125AX290S FAQ
Yes, the SI125AX290S is discontinued. The direct replacement is the SAI125AX290S. It shares the same ISO 15552 mounting interface, 125mm bore, 290mm stroke, force, and G1/2 port, fitting existing fixtures perfectly.
It features a G1/2 air port. Force output is 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX290S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX290S replacement — usually within 7-8 hours.