This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X170STC, 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 SI125X170STC
The AirTAC SI125 Standard Cylinder SI125X170STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 170mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X170STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke170 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X170STC
- 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 SI125X170STC
The AirTAC SI125X170STC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 170 mm stroke. It delivers a push force of 6136 N at 0.5 MPa via its G1/2 port. The direct replacement is the SAI125X170STC, which shares the same TC trunnion mounting, M27x2 rod thread, and output force.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL and BSAI lock variants absent in the legacy line, and the original -S magnet works with CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X170STC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X170STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X170STC |
| Bore size | Ø125 mm |
| Stroke | 170 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 SAI125X170STC 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 SAI125X170STC 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 SI125X170STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×170 | 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 SI125X170STC Is Used
Heavy Press Staging
Ideal for positioning heavy steel blanks at 6136 N push force before a hydraulic press cycle.
Pallet Diversion
Uses the 170 mm stroke to push loaded pallets onto secondary assembly lines safely.
Automated Crate Lift
Provides reliable vertical lifting of 313 kg crates using the TC trunnion mount for pivot.
Replacing the Airtac SI125 Standard Cylinder SI125X170STC with the SAI125X170STC
To replace the SI125X170STC, order the SAI125X170STC. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the exact 125 mm bore, 170 mm stroke, G1/2 port, and TC trunnion mount. The SAI uses an upgraded two Y-shaped one-way piston seal for low start-up pressure. If you need to size up or down, neighbouring bores offer different force classes, but this 125 mm bore provides push forces of 6136 N at 0.5 MPa, 8590 N at 0.7 MPa, and a theoretical max of 1251 kgf at 1.0 MPa. Note that a plain cylinder drifts on air loss; the air cushion only decelerates near stroke end. For load holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants. The -S magnet supports legacy CS1-B/DS1-B switches, while the SAI uses current AirTAC switches.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X170STC
- ✓ 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 SI125X170STC FAQ
Yes, the SI125X170STC is discontinued. The direct replacement is the SAI125X170STC. It is dimensionally interchangeable per ISO 15552, keeping the same 125 mm bore, 170 mm stroke, G1/2 port, TC mount, and force, but features an upgraded piston seal.
The G1/2 port feeds a 32 mm rod. It generates a push force of 6136 N and pull of 5734 N at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N at 0.9 MPa, and a max force of 1251 kgf at 1.0 MPa. Speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X170STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X170STC replacement — usually within 7-8 hours.