This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X70TC, 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 SI125X70TC
The AirTAC SI125 Standard Cylinder SI125X70TC 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 SAI125X70TC, 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 → SAI125X70TC
- 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 SI125X70TC
The AirTAC SI125X70TC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 70 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X70TC, a direct upgrade sharing the exact ISO 15552 mounting interface, TC trunnion, and force class.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. This specific SKU lacks the -S magnet, so it cannot accept CS1-B or DS1-B sensors. For load holding, note that a plain cylinder drifts on air loss—the cushion only decelerates.
Airtac SI125 Standard Cylinder SI125X70TC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X70TC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X70TC |
| 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 SAI125X70TC 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 SAI125X70TC 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 SI125X70TC
| 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 SI125X70TC Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring high thrust and robust TC trunnion alignment.
Pallet Diversion
Actuates heavy pallet lane diverters on high-throughput packaging and distribution lines.
Material Lift Gate
Raises and lowers substantial loading dock gates using the 6136 N push force at 0.5 MPa.
Replacing the Airtac SI125 Standard Cylinder SI125X70TC with the SAI125X70TC
To replace the SI125X70TC, order the SAI125X70TC. Confirm the ISO 15552 TC trunnion interface, 125 mm bore, 70 mm stroke, and G1/2 port. This non-magnetic SKU cannot take sensors; if sensing is needed, select an SAI variant with the -S suffix for current AirTAC switches. Sizing both ways: the 125 mm bore yields 6136 N push at 0.5 MPa (8590 N at 0.7 MPa), while the neighboring 100 mm bore offers 3927 N. Because the standard cylinder does not hold load without live air, use an external pilot check valve or explore the SAIL or BSAI lock variants for secure holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X70TC
- ✓ 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 SI125X70TC FAQ
Yes, the SI125X70TC is discontinued. The direct replacement is the SAI125X70TC. It shares the same ISO 15552 mounting interface, 125 mm bore, 70 mm stroke, G1/2 port, and TC trunnion, fitting existing fixtures perfectly.
The G1/2 port feeds a 32 mm rod. Forces 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 SAI125X70TC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X70TC replacement — usually within 7-8 hours.