This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X25SN, 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 SI125X25SN
The AirTAC SI125 Standard Cylinder SI125X25SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 25mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X25SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke25 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X25SN
- 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 SI125X25SN
The AirTAC SI125X25SN is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 25 mm stroke, G1/2 port, and 6136 N push force at 0.5 MPa. The direct replacement is the SAI125X25SN, matching the exact bore, stroke, output force, port size, and ISO 15552 mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. This -S/-N variant includes a piston magnet for CS1-B/DS1-B switches and NBR seals (-20 to +70 C); Viton H raises heat to 150 C.
Airtac SI125 Standard Cylinder SI125X25SN Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X25SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X25SN |
| Bore size | Ø125 mm |
| Stroke | 25 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 SAI125X25SN 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 SAI125X25SN 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 SI125X25SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×25 | 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 SI125X25SN Is Used
Heavy Stamping Press
Drives a 313 kg vertical tooling stack with its 6136 N push force at 0.5 MPa, utilizing the short 25 mm stroke for rapid, high-impact stamping cycles.
Mold Clamping Station
Secures heavy injection molds using the 125 mm bore profile barrel, relying on the G1/2 port to deliver high volume for rapid clamp actuation.
Pallet Diverter
Shifts substantial pallet loads laterally where a robust 32 mm rod and M27x2 thread are required to handle high side-load forces without deflection.
Replacing the Airtac SI125 Standard Cylinder SI125X25SN with the SAI125X25SN
To replace the SI125X25SN, order the SAI125X25SN direct, confirming the ISO 15552 mounting interface, 125 mm bore, 25 mm stroke, G1/2 port, and NBR seals. The piston magnet (-S) works with legacy CS1-B/DS1-B sensors, though the SAI uses current AirTAC switches. For sizing, the 125 mm bore yields 6136 N push at 0.5 MPa; dropping to an 80 mm bore gives 2513 N, while increasing to 160 mm provides 10053 N. A plain cylinder drifts on air loss as the cushion only decelerates; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Rod material options include carbon steel, SUS420J2 (A), or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X25SN
- ✓ 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 SI125X25SN FAQ
Yes, the AirTAC SI125X25SN is discontinued. The direct replacement is the SAI125X25SN. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 25 mm stroke, force, G1/2 port, and mounting interface to fit existing fixtures directly.
The 125 mm bore features a G1/2 port and delivers 6136 N push and 5734 N pull at 0.5 MPa. At 0.7 MPa push is 8590 N, and 11045 N at 0.9 MPa. The theoretical maximum force is 1251 kgf at 1.0 MPa, with an operating speed of 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X25SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X25SN replacement — usually within 7-8 hours.