This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX290, 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 SI125AX290
The AirTAC SI125 Standard Cylinder SI125AX290 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 SAI125AX290, 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 → SAI125AX290
- 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 SI125AX290
The AirTAC SI125AX290 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 290 mm stroke. It delivers 6136 N push force at 0.5 MPa and features a G1/2 port with an M27x2 rod thread. The direct replacement is the SAI125AX290, sharing the identical interface, force, and mounting.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. This SI125AX290 variant uses the SUS420J2 stainless rod (-A) and lacks a magnet, so it cannot take a sensor.
Airtac SI125 Standard Cylinder SI125AX290 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX290 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX290 |
| 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 SAI125AX290 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 SAI125AX290 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 SI125AX290
| 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 SI125AX290 Is Used
Heavy-Duty Pressing
Applies the 6136 N push force at 0.5 MPa to seat bearings or assemble heavy mechanical components with reliable pressure.
Automated Clamping
Secures large workpieces in machining fixtures, utilizing the SUS420J2 stainless rod for corrosion resistance in harsh environments.
Replacing the Airtac SI125 Standard Cylinder SI125AX290 with the SAI125AX290
To replace the SI125AX290, order the SAI125AX290. Confirm the ISO 15552 mounting interface, 125 mm bore, 290 mm stroke, G1/2 port, and your specific mounting accessory. Because this SKU lacks a magnet (-S), it cannot accept CS1-B/DS1-B sensors; order a magnet-equipped SAI if position sensing is required. At 290 mm stroke, guide rods are recommended to prevent side-load and rod-bending issues. For sizing, the 100 mm bore offers 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. Note that a plain cylinder drifts without live air; for load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX290
- ✓ 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 SI125AX290 FAQ
Yes, the SI125AX290 is discontinued. The direct replacement is the SAI125AX290. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 290 mm stroke, output force, G1/2 port, and mounting fixtures.
This double-acting cylinder has a G1/2 port. It delivers 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. The air cushion is 40 mm.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX290
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX290 replacement — usually within 7-8 hours.