This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X272, 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 SI125X272
The AirTAC SI125 Standard Cylinder SI125X272 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 272mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X272, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke272 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X272
- 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 SI125X272
The AirTAC SI125X272 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 272 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X272, matching the interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. It also adds SAIL and BSAI lock variants the SI lacked. This non-magnet SKU cannot take a sensor.
Airtac SI125 Standard Cylinder SI125X272 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X272 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X272 |
| Bore size | Ø125 mm |
| Stroke | 272 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 SAI125X272 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 SAI125X272 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 SI125X272
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×272 | 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 SI125X272 Is Used
Heavy Press Stamping
Drives large forming dies and heavy metal stamping presses requiring up to 6136 N of push force at 0.5 MPa.
Automated Clamp Fixtures
Secures large fabricated components during machining, utilizing the 32 mm rod and M27x2 thread for rigid clamping.
Replacing the Airtac SI125 Standard Cylinder SI125X272 with the SAI125X272
To replace the SI125X272, order the SAI125X272 and confirm the ISO 15552 mounting interface, 125 mm bore, 272 mm stroke, G1/2 port, and M27x2 rod thread. This 272 mm stroke is nonstandard (standard increments skip to 300 mm), so verify exact end-of-stroke dimensions. For sizing, a 100 mm bore gives 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. Because stroke exceeds 300 mm, use a guide to prevent rod bending and side-load wear. A plain cylinder drifts on air loss; for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. This no-S model cannot accept CS1-B/DS1-B sensors.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X272
- ✓ 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 SI125X272 FAQ
Yes, the SI125X272 is discontinued. The direct replacement is the SAI125X272. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 272 mm stroke, G1/2 port, and mounting accessories.
It features a G1/2 port and M27x2 rod thread. 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. Speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X272
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X272 replacement — usually within 7-8 hours.