This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X70, 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 SI125X70
The AirTAC SI125 Standard Cylinder SI125X70 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 70mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X70, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke70 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X70
- 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 SI125X70
The AirTAC SI125X70 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 70 mm stroke, delivering a push force of 6136 N at 0.5 MPa. AirTAC replaced this legacy unit with the SAI125X70 direct replacement. It shares the exact same ISO 15552 mounting interface, G1/2 port, and output force, so it drops directly into existing fixtures.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this specific SKU lacks a magnet (-S) and cannot accept a CS1-B/DS1-B sensor. If you need load holding on air loss, explore the SAIL or BSAI lock variants, as standard cushions only decelerate.
Airtac SI125 Standard Cylinder SI125X70 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X70 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X70 |
| Bore size | Ø125 mm |
| Stroke | 70 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 SAI125X70 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 SAI125X70 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 SI125X70
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×70 | 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 SI125X70 Is Used
Heavy Press Clamping
Ideal for applying high 6136 N clamping force to secure large automotive castings during CNC machining operations.
Injection Mold Ejection
Drives heavy ejection pins on large molding equipment, utilizing the 70 mm stroke to clear bulky plastic parts efficiently.
Replacing the Airtac SI125 Standard Cylinder SI125X70 with the SAI125X70
To replace the discontinued SI125X70, order the SAI125X70. Confirm the ISO 15552 mounting interface, the 125 mm bore, the 70 mm stroke, and the G1/2 port. Because this SKU has no -S suffix, it cannot support legacy CS1-B/DS1-B sensors; if position detection is needed, select a magnet-equipped SAI model. When sizing, neighboring bores offer different forces: the 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. A plain cylinder drifts on air loss—cushions only decelerate—so for suspended loads use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X70
- ✓ 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 SI125X70 FAQ
Yes, the AirTAC SI125X70 is discontinued. The direct replacement is the SAI125X70, which shares the identical ISO 15552 mounting interface, 125 mm bore, 70 mm stroke, output force, and G1/2 port for a seamless fixture swap.
This 125 mm bore cylinder uses a G1/2 air port. At 0.5 MPa it provides 6136 N push and 5734 pull force. At 0.7 MPa push is 8590 N, at 0.9 MPa it is 11045 N, and the theoretical maximum is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X70
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X70 replacement — usually within 7-8 hours.