This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X265S, 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 SI125X265S
The AirTAC SI125 Standard Cylinder SI125X265S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 265mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X265S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke265 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X265S
- 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 SI125X265S
The AirTAC SI125X265S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 265 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. AirTAC replaced this legacy unit with the SAI125X265S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI successor features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SI line lacked integrated lock variants, but the SAI family adds SAIL and BSAI clamp-lock options. This -S model includes a piston magnet for CS1-B/DS1-B switches.
Airtac SI125 Standard Cylinder SI125X265S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X265S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X265S |
| Bore size | Ø125 mm |
| Stroke | 265 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 SAI125X265S 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 SAI125X265S 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 SI125X265S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×265 | 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 SI125X265S Is Used
Heavy Stamping Press
Drives large platens and stamping dies requiring 6136 N push force at 0.5 MPa, utilizing the 265 mm stroke to form thick metal components.
Automated Assembly Fixture
Actuates large clamping mechanisms in automotive fixtures, relying on the G1/2 port and 125 mm bore for high-volume air flow and thrust.
Replacing the Airtac SI125 Standard Cylinder SI125X265S with the SAI125X265S
To replace the SI125X265S, order the SAI125X265S. Confirm the ISO 15552 mounting interface, 125 mm bore, 265 mm stroke, G1/2 port (PT/G/NPT thread), and your mounting accessory. This -S SKU has a magnet for CS1-B/DS1-B switches; the SAI uses current AirTAC switches. For sizing, a 100 mm bore offers 3927 N push at 0.5 MPa, while an 80 mm bore provides 2513 N; stepping up to 160 mm yields 10053 N. A plain cylinder drifts on air loss as the cushion only decelerates, so use the SAIL or BSAI lock variant, an external rod lock, or a pilot check valve to hold loads. The 32 mm rod and M27x2 thread handle high thrust. At 265 mm stroke, verify guide alignment to prevent rod bending and side-load wear. Operating speed is 30-500 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X265S
- ✓ 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 SI125X265S FAQ
Yes, the SI125X265S is discontinued. The direct replacement is the AirTAC SAI125X265S. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 265 mm stroke, 6136 N force, G1/2 port, and mounting interface.
The 125 mm bore features a G1/2 air port and M27x2 rod thread. It generates 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X265S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X265S replacement — usually within 7-8 hours.