This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX270, 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 SI125AX270
The AirTAC SI125 Standard Cylinder SI125AX270 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 270mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX270, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke270 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX270
- 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 SI125AX270
The AirTAC SI125AX270 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 270 mm stroke. It delivers 6136 N push and 5734 pull at 0.5 MPa, utilizing a G1/2 port and an M27x2 rod thread. The direct successor is the SAI125AX270, retaining the same interface, force class, and dimensions.
This SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The original SI line lacked the SAIL air-released lock, SAIF valve, and BSAI clamp-lock variants now available. Note this specific SKU uses a SUS420J2 stainless rod (-A) but lacks a magnet, so it cannot accept CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125AX270 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX270 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX270 |
| Bore size | Ø125 mm |
| Stroke | 270 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 SAI125AX270 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 SAI125AX270 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 SI125AX270
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×270 | 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 SI125AX270 Is Used
Heavy Stamp Pressing
Provides 6136 N of thrust at 0.5 MPa for securing heavy metal sheets in automated stamping fixtures, utilizing the SUS420J2 rod to resist moisture.
Pallet Redirector
Acts as a robust diverter arm in high-capacity conveyor lines, moving loaded pallets laterally with a 313 kg safe vertical-lift margin.
Mold Clamping Unit
Holds large injection molds or heavy industrial castings in place during machining, relying on the 125 mm bore's 1251 kgf maximum theoretical force.
Replacing the Airtac SI125 Standard Cylinder SI125AX270 with the SAI125AX270
To replace the SI125AX270, order the SAI125AX270. Confirm the ISO 15552 mounting interface, the 270 mm stroke, G1/2 port, and your specific mounting accessory (LB, FA, TC, etc.). Because this SKU lacks the -S magnet, it cannot support position sensing; if switches are needed, specify a magnet on the new unit. For load holding, remember a standard cylinder drifts on air loss—the cushion only decelerates—so add an external rod lock, pilot check valve, or switch to the SAIL/BSAI lock variant. Operating speed is 30-500 mm/s. At 270 mm stroke, side-load and rod-bending risks are moderate; ensure proper guide alignment to prevent premature seal wear. If downsizing, a 100 mm bore gives 3927 N push at 0.5 MPa; if upsizing, a 160 mm bore yields 10053 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX270
- ✓ 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 SI125AX270 FAQ
Yes, the AirTAC SI125AX270 is discontinued. The direct replacement is the SAI125AX270. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 270 mm stroke, G1/2 port, and mounting interface, but features an upgraded two Y-shaped one-way piston seal.
This double-acting cylinder has a G1/2 port. It generates 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, and 11045 N push at 0.9 MPa. The theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX270
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX270 replacement — usually within 7-8 hours.