This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X290S, 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 SI125X290S
The AirTAC SI125 Standard Cylinder SI125X290S 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 SAI125X290S, 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 → SAI125X290S
- 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 SI125X290S
The AirTAC SI125X290S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore, 290mm stroke, and a built-in piston magnet for CS1-B/DS1-B switches. It delivers 6136N push force at 0.5MPa via a G1/2 port. AirTAC replaced this legacy unit with the SAI125X290S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. It also introduces variants the SI lacked, like the SAIL air-released lock and BSAI clamp-lock.
Airtac SI125 Standard Cylinder SI125X290S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X290S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X290S |
| 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 SAI125X290S 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 SAI125X290S 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 SI125X290S
| 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 SI125X290S Is Used
Heavy Pressing
Drives large stamping and forming presses requiring up to 11045N of thrust at 0.9MPa with stable 290mm travel.
Pallet Handling
Indexes heavy loaded pallets on conveyor lines, utilizing the 313kg vertical lift margin to shift substantial weights.
Automated Clamping
Secures large fabricated components during machining or welding operations using robust 125mm bore clamping force.
Replacing the Airtac SI125 Standard Cylinder SI125X290S with the SAI125X290S
To replace the SI125X290S, order the SAI125X290S and verify the ISO 15552 mounting interface, 125mm bore, 290mm stroke, G1/2 port, and mounting accessory. Keep the -S magnet option for current AirTAC switch compatibility. Sizing both ways: the neighboring 100mm bore yields 3927N push at 0.5MPa, while stepping up to 160mm provides 10053N. At 290mm stroke, ensure adequate guide support to prevent rod bending and side-load wear. A plain cylinder drifts on air loss; the cushion only decelerates. For held loads, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X290S
- ✓ 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 SI125X290S FAQ
Yes, the SI125X290S is discontinued. The direct replacement is the SAI125X290S. It shares the identical ISO 15552 mounting interface, 125mm bore, 290mm stroke, output force, and G1/2 port, fitting directly into existing fixtures.
This 125mm bore cylinder uses a G1/2 air port. It generates 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and a theoretical maximum force of 1251 kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X290S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X290S replacement — usually within 7-8 hours.