This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X35, 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 SI125X35
The AirTAC SI125 Standard Cylinder SI125X35 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 35mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X35, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke35 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X35
- 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 SI125X35
The AirTAC SI125X35 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 35 mm stroke. Generating 6136 N push force at 0.5 MPa, it is replaced directly by the SAI125X35. This direct upgrade shares the exact same G1/2 port, M27x2 rod thread, and mounting dimensions. The SAI features an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life.
Because this specific SKU lacks the -S magnet suffix, it cannot accept legacy CS1-B or DS1-B sensors. The SAI family also introduces variants the SI lacked, such as the SAIL air-released lock and BSAI clamp-lock. Note that a standard cylinder does not hold load without live air; the 40 mm adjustable cushions only decelerate near stroke ends. For high-temperature environments up to 150 C, a Viton H seal option is available.
Airtac SI125 Standard Cylinder SI125X35 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X35 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X35 |
| Bore size | Ø125 mm |
| Stroke | 35 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 SAI125X35 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 SAI125X35 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 SI125X35
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×35 | 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 SI125X35 Is Used
Heavy Stamping Press
Drives heavy-duty stamping and forming dies requiring high push force over a short 35 mm travel distance.
Industrial Clamp
Secures large fabricated steel components in welding fixtures with a robust 313 kg vertical lift capacity.
Press Fit Assembly
Applies steady 6136 N downward pressure to seat bearings and bushings into heavy machinery housings.
Replacing the Airtac SI125 Standard Cylinder SI125X35 with the SAI125X35
To replace the SI125X35, order the SAI125X35, confirming the ISO 15552 interface, 125 mm bore, 35 mm stroke, G1/2 port, and mounting accessory. Since this SKU has no -S magnet, it cannot support position sensing. If you need to size up or down, neighbouring bores are 100 mm and 160 mm. At 0.5 MPa, the 100 mm bore yields 3927 N push, while the 160 mm bore yields 10053 N. For load holding, remember a plain cylinder drifts on air loss; the cushions only decelerate. Use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants for secure holding. Operating speed is 30-500 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X35
- ✓ 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 SI125X35 FAQ
Yes, the AirTAC SI125X35 is discontinued. The direct replacement is the SAI125X35. It shares the same ISO 15552 mounting interface, 125 mm bore, 35 mm stroke, output force, G1/2 port, and accessories, fitting existing fixtures perfectly.
The bore is 125 mm with a G1/2 air port. Force ratings are: 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 SAI125X35
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X35 replacement — usually within 7-8 hours.