This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX225, 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 SI125AX225
The AirTAC SI125 Standard Cylinder SI125AX225 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 225mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX225, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke225 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX225
- 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 SI125AX225
The AirTAC SI125AX225 is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore and 225mm stroke. It delivers 6136N push and 5734N pull at 0.5MPa, utilizing a G1/2 port and M27x2 rod thread. AirTAC replaced this legacy unit with the SAI125AX225, a direct replacement sharing the exact ISO 15552 mounting interface, output force, and dimensions. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life.
Since this SKU lacks the -S magnet, it cannot accept a position switch and requires external sensing if needed. The -A code specifies a SUS420J2 stainless piston rod for corrosion resistance over the default carbon steel. Note that a plain cylinder drifts without live air; use the SAIL or BSAI lock variants for rigid holding.
Airtac SI125 Standard Cylinder SI125AX225 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX225 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX225 |
| Bore size | Ø125 mm |
| Stroke | 225 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 SAI125AX225 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 SAI125AX225 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 SI125AX225
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×225 | 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 SI125AX225 Is Used
Heavy Stamping Press
Drives heavy tooling in automated stamping lines, utilizing the 6136N push force at 0.5MPa to form thick-gauge metal components reliably.
Injection Mold Clamp
Secures large injection molding halves or heavy industrial fixtures, benefiting from the SUS420J2 stainless rod option in humid production environments.
Replacing the Airtac SI125 Standard Cylinder SI125AX225 with the SAI125AX225
To replace the discontinued SI125AX225, order the SAI125AX225. Verify your ISO 15552 mounting fixture (LB, FA, TC, etc.), the 225mm stroke, and the G1/2 port. This SKU has no -S magnet, so it cannot support legacy CS1-B/DS1-B switches; add the magnet if sensing is required. Sizing both ways: a 100mm bore yields 3927N push at 0.5MPa, while a 160mm bore yields 10053N. The 125mm bore gives 6136N push and 8590N at 0.7MPa. The 225mm stroke is under the 1500mm max standard, avoiding nonstandard limits. For side loads over 300mm, use a guide to prevent rod bending. The cushion only decelerates; for load holding on air loss, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX225
- ✓ 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 SI125AX225 FAQ
Yes, the SI125AX225 is discontinued. The direct replacement is the SAI125AX225. It shares the identical ISO 15552 mounting interface, 125mm bore, 225mm stroke, G1/2 port, and force ratings, fitting directly into existing fixtures.
It features a G1/2 air port and M27x2 rod thread. Force output is 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N at 0.9MPa, with a theoretical max of 1251 kgf at 1.0MPa. Speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX225
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX225 replacement — usually within 7-8 hours.